charheep
Cleared for Takeoff
Are the replacements about the same size, or will there be a bit of fabrication needed?
Thinking about a Bus/RV
- Thread starter Ted
- Start date
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I debated on this one some. If I was going #fullted, I would get some 110V mini-splits and mount those. That would require fabrication, and it would also give me the benefit of having some units that would work down to something like -4F or -13F. While we probably won't be RVing with it that cold out, we have RV'd with it in the mid to low teens, and we removed the propane heater (not likely to put that back in, although I might do something). This would require a lot of fabrication, as there is no good place to mount your standard mini split head units, and the ceiling cassettes are significantly larger (like about 10" in each dimension) than the standard RV units. I could put those in, but I think it would be too much work.
What I'm looking at are some new standard RV rooftop AC/heat pumps, which are supposed to be quieter, and more like mini splits in a single unit just with the form factor of a standard RV rooftop unit. The problem is that they will only work down to something slightly below freezing. We have thus far made due just fine with a couple of space heaters, and with how well-insulated the RV is now, that does just fine even in the teens (while parked).
So, summary is, if I go the way I'm planning it will be a bolt-in replacement essentially.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
This is NOT a serious video that has anything relating to actual work. But @jesse sent me a case of Amsoil coolant booster, so I threw it in the RV.
I am only posting this here for potential entertainment value since another PoAer sent it to me.
If I get something sent to me, 99% chance I will do something with it. However the timeline of that may take a while.
I am only posting this here for potential entertainment value since another PoAer sent it to me.
If I get something sent to me, 99% chance I will do something with it. However the timeline of that may take a while.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I'm always looking at experimenting with new things, and one thing I've been thinking about is adding a water-methanol injection setup to the bus. The primary use case that I'm looking at for this is extended slower climbs where the cooling system is being taxed and the engine is having to work at higher power settings for longer periods of time. Our trip out west this summer will have a lot of those. Water/meth injection seems to be good at cooling induction temps (which are good for everything), but what I'm also looking at is reducing the intercooler's portion of the heat load that the cooling system has to absorb, which should let me turn up my cooling fans some more and help cooling further. Also, it's something I've never messed with before, so mainly I'm just interested in seeing what it does.
Since I'm not looking for max horsepower, my thought is I would probably run a smaller amount of water/meth mix than would typically be used on an engine of this power, and just accept a reduced intake air temp that goes with that as sufficient. One thing with the proposed setup, though, would be putting the mixture in ahead of the intercooler, rather than after. There are some warnings about that, as the liquid can pool up in the intercooler and cause hydrolock, but I don't think that would be much of a concern with how I'd run it. For one, I would be setting it to only come on at higher boost conditions (and thus higher intake temps, so more likely of boiling things off), but I would also not just be leaving it on anytime the engine was on - it would only be for specific portions of a drive during the use case, and that would also give a good bit of driving time for anything left in there to boil off.
Has anyone on here dealt with water/meth injection before, especially on a diesel, and have thoughts on it before I pull the trigger on a system?
Since I'm not looking for max horsepower, my thought is I would probably run a smaller amount of water/meth mix than would typically be used on an engine of this power, and just accept a reduced intake air temp that goes with that as sufficient. One thing with the proposed setup, though, would be putting the mixture in ahead of the intercooler, rather than after. There are some warnings about that, as the liquid can pool up in the intercooler and cause hydrolock, but I don't think that would be much of a concern with how I'd run it. For one, I would be setting it to only come on at higher boost conditions (and thus higher intake temps, so more likely of boiling things off), but I would also not just be leaving it on anytime the engine was on - it would only be for specific portions of a drive during the use case, and that would also give a good bit of driving time for anything left in there to boil off.
Has anyone on here dealt with water/meth injection before, especially on a diesel, and have thoughts on it before I pull the trigger on a system?
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Now that the school year is done and I got the Cobra driving in time to drive the kids to/from school for it, it's time to get back to focusing on the bus to prepare for summer travels.
I decided to go ahead and order the water/methanol injection kit. I ordered one from AEM with a 5-gallon tank. It has three different nozzles, 250, 500, and 1000 cc/min. Given that my engine's horsepower (330 HP) and my goals (lowering IATs, and with that reducing heat load on the radiator/intercooler setup - not necessarily going for max lowering/max performance), I'm going to plan to start off with the smallest 250cc/min setup and adjust from there. The controller will scale the flow rate with boost, and I should have some room to play with it. Ideally, the idea would be that a 5 gallon tank should last me at least one day's worth of driving for the sections where I'm going to be running it - and those sections are specifically intended to be extended climbs at lower speeds. A long day for us in the bus can be 10+ hours, but obviously that does not involve any sort of continuous injection that would go with it, it would just be for harder sections. Like most of the projects I've done on this bus, I'm going about things different than conventional logic/wisdom, but I think it will work.
We got the old rooftop heat pump/ACs off and got the new ones up, but not fully installed yet. I put them in place and then wired them up to see if 1) they worked and 2) initial impressions. I think they will be a noticeable improvement. The biggest improvement that I found right off the bat was that the compressor was completely silent internally for turning on and off. That was one of my big complaints with the old units and disturbed sleeping with the fans on. Another interesting note is that these units have three fan settings rather than just two, which also should help with keeping the sound down. I'm looking forward to finishing getting them up.
The bedroom is getting new updates in the form of a new TV (replacing a 2010 era 22" flat screen with a new 27" flat screen - the biggest I can fit in the available space) and a sound bar with a subwoofer mounted under the bed. The bedroom TV has always suffered from poor (by today's standards) video and audio quality. While we don't watch very much TV, we like to be able to enjoy it when we do. The subwoofer under the bed will be a nice use of that open space that is otherwise unutilized.
The toilet on the RV appears to be original and so is its base seal. On the last trip it was leaking. We decided to just go ahead and buy a new toilet to replace it, which should hopefully have better function and appearance.
Lastly, I need to pull the generator and give it a good once-through. I was dreading that because of the lack of good access to do it, but it shouldn't be too awful. The work I did to mount it on air springs will make it a lot easier to unmount it. Height wise, it's 22", and even in the bus's current state with the springs deflated, there's 17" of clearance between the front bumper/fiberglass and the ground. It won't take much to get those extra 5". Once out, I'll take the cover off and assess which parts I need and what should be replaced for maintenance and to make sure it's reliable for us on our trip. Most of all, I hope that results in it being quieter. The air mounts helped with that, but it's still quite loud.
I decided to go ahead and order the water/methanol injection kit. I ordered one from AEM with a 5-gallon tank. It has three different nozzles, 250, 500, and 1000 cc/min. Given that my engine's horsepower (330 HP) and my goals (lowering IATs, and with that reducing heat load on the radiator/intercooler setup - not necessarily going for max lowering/max performance), I'm going to plan to start off with the smallest 250cc/min setup and adjust from there. The controller will scale the flow rate with boost, and I should have some room to play with it. Ideally, the idea would be that a 5 gallon tank should last me at least one day's worth of driving for the sections where I'm going to be running it - and those sections are specifically intended to be extended climbs at lower speeds. A long day for us in the bus can be 10+ hours, but obviously that does not involve any sort of continuous injection that would go with it, it would just be for harder sections. Like most of the projects I've done on this bus, I'm going about things different than conventional logic/wisdom, but I think it will work.
We got the old rooftop heat pump/ACs off and got the new ones up, but not fully installed yet. I put them in place and then wired them up to see if 1) they worked and 2) initial impressions. I think they will be a noticeable improvement. The biggest improvement that I found right off the bat was that the compressor was completely silent internally for turning on and off. That was one of my big complaints with the old units and disturbed sleeping with the fans on. Another interesting note is that these units have three fan settings rather than just two, which also should help with keeping the sound down. I'm looking forward to finishing getting them up.
The bedroom is getting new updates in the form of a new TV (replacing a 2010 era 22" flat screen with a new 27" flat screen - the biggest I can fit in the available space) and a sound bar with a subwoofer mounted under the bed. The bedroom TV has always suffered from poor (by today's standards) video and audio quality. While we don't watch very much TV, we like to be able to enjoy it when we do. The subwoofer under the bed will be a nice use of that open space that is otherwise unutilized.
The toilet on the RV appears to be original and so is its base seal. On the last trip it was leaking. We decided to just go ahead and buy a new toilet to replace it, which should hopefully have better function and appearance.
Lastly, I need to pull the generator and give it a good once-through. I was dreading that because of the lack of good access to do it, but it shouldn't be too awful. The work I did to mount it on air springs will make it a lot easier to unmount it. Height wise, it's 22", and even in the bus's current state with the springs deflated, there's 17" of clearance between the front bumper/fiberglass and the ground. It won't take much to get those extra 5". Once out, I'll take the cover off and assess which parts I need and what should be replaced for maintenance and to make sure it's reliable for us on our trip. Most of all, I hope that results in it being quieter. The air mounts helped with that, but it's still quite loud.
CJones
Final Approach
But the real question is... what direction are y'all headed this time? We've got some friends doing a road trip up to Yellowstone and back - planning to camp the whole way. I was helping them figure out how BLM/NFS land works and how to use those maps to their advantage. That has just reinvigorated my itch to do some exploring. Hoping to get into the hills and hollers of N. Ga. mtns soon.
...which reminds me, I need to look for some new CAs and SYE for the Jeep.
...which reminds me, I need to look for some new CAs and SYE for the Jeep.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Our next trip will be heading out west, checking out the northern half of California and other things, and we'll plan to be at Bonneville for part of speed week.
To be honest I'm not 100% sure of the planned schedule, but I know enough of it to know that it will be hot and there will be serious mountains, hence part of my extra attention to systems that involve both 1) interior comfort and 2) engine cooling.
Another system that I may add depending on timing is a mister for the radiator/intercooler. I'll probably see how much time I have left after I get the other more important things done (especially if I have a chance to see what the water/methanol does first) and then maybe add it. Ultimately I know the bus well and sometimes you just have to accept a slow slog on an uphill, and I've never not been able to make that work so far with the electric fans.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I actually found that the record at Bonneville for a Class A is 122 MPH (going off of memory). That's not very fast and I'm pretty well certain I could beat that, but not in this bus the way it's geared. 2400 RPM (at which point the fuel cut-off starts kicking in) would end up being something in the high 90s.
There are marine versions of the 3126/C7 that I think will rev up to 2800 and so if I could get a file for one of those maybe I could make it work, but that still would be under 122. So I'd either have to really rev the snot out of this engine and get into experimental territory, regear it, or look at something different altogether. Definitely not happening this year.
- Joined
- Jul 21, 2014
- Messages
- 9,770
- Location
- Broken Arrow, OK
- Display Name
Display name:
SoonerAviator
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Aero would definitely become a thing at that point. I would need more than the 330 HP I have now, but I that's a relatively easy to overcome item.
I've noticed that, except in extremely calm wind conditions, the bus does get a lot of aerodynamic flutter/turbulence above 85 MPH IAS/TAS (really haven't experimented enough to determine which one of those it is). Of course if it's very windy (unless that wind is a tailwind) I probably am not going that fast. The airtabs helped significantly, I would probably need to look at more additional/other aero at that speed, but most of all the winds would need to be calm.
charheep
Cleared for Takeoff
brcase
En-Route
Reminds me of the year at Reno when they cancelled the Formula One Race just after the Golden Knights (Army Parachute Team) took off in the C-130.
They also cancelled the Golden Knights drop as well, so to fill in the time they had the C-130 flying the race course with the Golden Knights standing in the door making sure they didn't cut any Pylons.
Brian
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
That's what we had before and that's what we're getting again. We're going with a different model from previous, so hopefully we're happy/happier with it.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I managed to get a little shop time and made some progress on the TV/sound system upgrade in the bedroom. There's a nook under the bed (which is on the slide) where the subwoofer can fit and won't interfere with the slide mechanism. I secured it (with big zip ties) and sound tested it - no vibrations or rattles - and very good sound and bass. It should be a nice upgrade, along with going from a 22" 2010-era flat screen to a new 27". Of course anything is better than the probably 13-15" CRT that was in there from the factory, but still - may as well make it nicer and more updated.
Thinking about the blocks of time I'll have over the coming weeks, I think my plan will be to try to finish up the rooftop AC install and the bedroom TV work, maybe the toilet as well (that's really a 5 minute thing once I get the gasket) and then pull the generator and get it apart with a full parts list of what I want to replace and get those coming. Belts and hoses I know, I'm going to guess motor mounts, but once I get the cover off I'll be able to see better. Hopefully somewhere in there the water/methanol injection kit arrives and I can install that while waiting on parts for the generator, then put the generator back in. And while the generator's out, put some sound deadening on the floor above it - not that the inside has much noise now anyway, but it should also reduce road noise.
Another thing I want to do before this trip that should be quick is to replace the harmonic damper on the engine. It's original which makes it around 23 years old, and they're known to harden and wear out. While the engine isn't giving me indications of problems, it seems that a lot of people with Cats are in favor of preemptive replacement on them after a certain age. I've been thinking about it for a while and it's an easy one to do, so I may as well just go ahead and do it.
Thinking about the blocks of time I'll have over the coming weeks, I think my plan will be to try to finish up the rooftop AC install and the bedroom TV work, maybe the toilet as well (that's really a 5 minute thing once I get the gasket) and then pull the generator and get it apart with a full parts list of what I want to replace and get those coming. Belts and hoses I know, I'm going to guess motor mounts, but once I get the cover off I'll be able to see better. Hopefully somewhere in there the water/methanol injection kit arrives and I can install that while waiting on parts for the generator, then put the generator back in. And while the generator's out, put some sound deadening on the floor above it - not that the inside has much noise now anyway, but it should also reduce road noise.
Another thing I want to do before this trip that should be quick is to replace the harmonic damper on the engine. It's original which makes it around 23 years old, and they're known to harden and wear out. While the engine isn't giving me indications of problems, it seems that a lot of people with Cats are in favor of preemptive replacement on them after a certain age. I've been thinking about it for a while and it's an easy one to do, so I may as well just go ahead and do it.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Here and there, I've managed to get more progress on the RV to prepare for summer travels.
- The new bedroom TV (27" up from 22", 2023 model up from 2010 model) is installed. Much better smart functionality, and a much higher quality and larger screen
- Completed install of the Klipsch sound bar and subwoofer. Much improved bedroom sound, and, somewhat to my surprise, no rattling from the subwoofer
- The new rooftop AC units are installed and fully functioning. They both blow out cold air (as you'd hope) and the seal around them is all completed. The sound reduction is noticeable, much better. I'm looking forward to these, since as they make 15k btus rather than 13.5k, they should also help keep the bus cooler (and apparently, with the lack of standardization in RV ACs, their 15k is better than a lot of other 15ks)
- Oil, oil filter, and both fuel filters are changed and ready to go
I pulled the toilet out and we were originally going to replace it. However, because of how this RV and its black tank are designed, really no other toilet will work besides what we have due to size issues. Well, they sell a new base for the toilet (with all the mechanisms - just attaches to the bowl) so I ordered a new one of those, as well as the new flusher valve in back. I'll get it all reassembled/refurbished and then with a new seat/lid, we should be completely set there. My wife is going to tile the area around the toilet as well, so that will be a nice addition/finishing touch to the toilet closet.
In the process of this, I've found that RV toilets have absolutely no standardization whatsoever, which is aggravating, but oh well.
Another thing I've done is I ordered a 50 gallon fresh water tank. The stock capacity is 85 (I think?) gallons, which really has been on the low side for us. I found a 50 gallon tank that will fit in one of the unused bay areas and that will be a nice addition. I'll have to figure out some relevant plumbing and it won't be completely seamless, but it will be a good improvement.
I ordered a new damper from Cat which should arrive sometime next week, and that'll be quick to throw on. I've had a recurring issue on the bus since buying it where one bolt that holds on the lower alternator (previously the AC compressor) gets really, really beaten up. I've seen issues like this happen on engines with harmonic balancers being off before, so I guess we'll see if any difference is observable. Obviously this isn't a catastrophic issue, but after 23 years and 119k miles (mostly the 23 years portion), it's worth doing.
With some of these minor things underway or otherwise taken care of, the next big thing (probably over the weekend) will be pulling the generator to service it.
- The new bedroom TV (27" up from 22", 2023 model up from 2010 model) is installed. Much better smart functionality, and a much higher quality and larger screen
- Completed install of the Klipsch sound bar and subwoofer. Much improved bedroom sound, and, somewhat to my surprise, no rattling from the subwoofer
- The new rooftop AC units are installed and fully functioning. They both blow out cold air (as you'd hope) and the seal around them is all completed. The sound reduction is noticeable, much better. I'm looking forward to these, since as they make 15k btus rather than 13.5k, they should also help keep the bus cooler (and apparently, with the lack of standardization in RV ACs, their 15k is better than a lot of other 15ks)
- Oil, oil filter, and both fuel filters are changed and ready to go
I pulled the toilet out and we were originally going to replace it. However, because of how this RV and its black tank are designed, really no other toilet will work besides what we have due to size issues. Well, they sell a new base for the toilet (with all the mechanisms - just attaches to the bowl) so I ordered a new one of those, as well as the new flusher valve in back. I'll get it all reassembled/refurbished and then with a new seat/lid, we should be completely set there. My wife is going to tile the area around the toilet as well, so that will be a nice addition/finishing touch to the toilet closet.
In the process of this, I've found that RV toilets have absolutely no standardization whatsoever, which is aggravating, but oh well.
Another thing I've done is I ordered a 50 gallon fresh water tank. The stock capacity is 85 (I think?) gallons, which really has been on the low side for us. I found a 50 gallon tank that will fit in one of the unused bay areas and that will be a nice addition. I'll have to figure out some relevant plumbing and it won't be completely seamless, but it will be a good improvement.
I ordered a new damper from Cat which should arrive sometime next week, and that'll be quick to throw on. I've had a recurring issue on the bus since buying it where one bolt that holds on the lower alternator (previously the AC compressor) gets really, really beaten up. I've seen issues like this happen on engines with harmonic balancers being off before, so I guess we'll see if any difference is observable. Obviously this isn't a catastrophic issue, but after 23 years and 119k miles (mostly the 23 years portion), it's worth doing.
With some of these minor things underway or otherwise taken care of, the next big thing (probably over the weekend) will be pulling the generator to service it.
- Joined
- Jul 23, 2021
- Messages
- 3,888
- Display Name
Display name:
Albany Tom
Sounds like lots of progress! I may have mentioned a this before, or others, or you already know, but if not... A lot of older RV's had polybutylene plumbing on the fresh water side. I've worked with it, back when I was a teenager and everyone said it was "fine", and it is not. It deserves the reputation is has, and it's worse than that.
The other plumbing tip I have is that solvent fittings for PVC drain lines works great in a house, but if you drive like I drove, the pipes or joints can snap from time to time. So I used to re-plumb them using GE silicone instead of solvent to give them some flex. It might sound goofy, but it worked.
The other plumbing tip I have is that solvent fittings for PVC drain lines works great in a house, but if you drive like I drove, the pipes or joints can snap from time to time. So I used to re-plumb them using GE silicone instead of solvent to give them some flex. It might sound goofy, but it worked.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
As far as I've been able to tell, the freshwater piping is all pex and not polybutylene. I'm no expert on this matter, but it's all in red and blue, and feels like the pex I've been using elsewhere. This RV is a 2000, which from my Google-fu should be after polybutylene was no longer used in homes and hopefully not in RVs. I've touched a lot of the plumbing at this point and none of it has seemed to be in bad shape for its age, which is fortunate. The system runs at a max of 55 psi (and I also have a pressure regulator for incoming water) so it never runs at a very high pressure either.
Interesting tip on the drains, thanks. So far I've been good there, knock on wood.
- Joined
- Jul 23, 2021
- Messages
- 3,888
- Display Name
Display name:
Albany Tom
It makes sense that the PB is gone. It was all medium grey, with compression fittings that would crack. Pex sounds perfect for an RV, light and flexible.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Yesterday the big job was getting the generator pulled out. I made it harder than I had to (mostly because I'd never pulled it before) and now I know enough to make it easier going back in... I hope.
Although dusty, the generator is overall not in bad shape:
But I did find a few issues. For one, as expected, the belt was awful. Literally every single rib was cracked, most all the way to the edge. I don't know how it didn't break:
Clearly original. The recommended interval is 6 years or 1000 hours I believe, this is 23 years and 2400 hours.
The valves were way out as well. Spec is 0.0057 - 0.0073" (which is an odd level of specificity, but ok) and intakes were 0.008-0.010", exhausts were 0.014"-0.016". I got those properly set.
I found two loose items that could potentially be sources of noise/rattling, although I didn't see anything that struck me as a smoking gun. The generator can be run outside of the bus and so I'm going to plan to do that and see if it seems things have quieted or alternately if I can figure out what might be making noise. I'm not convinced the rattling items I found are enough on their own, but it's possible. One of the things that these Quiet Diesel 7500s are apparently known for is chucking magnets. Unfortunately I could see some kind of rattling/hitting being the kind of noise I'm hearing, although the noise from the generator has been constant for the entire time we've had the RV and not gotten worse, so it seems unlikely that in the 1,000 hours and 3 years of run time a loose item wouldn't have let go by now. Manually turning the engine over I don't hear any funny noises from the engine or the generator part, but I'll look at it further.
With the generator out of the bus one of the things I'm going to do is apply Rockmat and sound deadening material to metal floor above the generator. That has nothing and produces a noticeable tin canning effect, which could be influencing things some.
I'm probably overthinking this, since the absolute worst case scenario is I could buy a portable generator and get power that way to deal with getting back home in case of a failure, and I'm addressing all of the most likely failure points and maintenance issues. But this is what I do and I try hard to make sure that we suffer no breakdowns or issues on our trips, which so far has been pretty successful.
Although dusty, the generator is overall not in bad shape:
But I did find a few issues. For one, as expected, the belt was awful. Literally every single rib was cracked, most all the way to the edge. I don't know how it didn't break:
Clearly original. The recommended interval is 6 years or 1000 hours I believe, this is 23 years and 2400 hours.
The valves were way out as well. Spec is 0.0057 - 0.0073" (which is an odd level of specificity, but ok) and intakes were 0.008-0.010", exhausts were 0.014"-0.016". I got those properly set.
I found two loose items that could potentially be sources of noise/rattling, although I didn't see anything that struck me as a smoking gun. The generator can be run outside of the bus and so I'm going to plan to do that and see if it seems things have quieted or alternately if I can figure out what might be making noise. I'm not convinced the rattling items I found are enough on their own, but it's possible. One of the things that these Quiet Diesel 7500s are apparently known for is chucking magnets. Unfortunately I could see some kind of rattling/hitting being the kind of noise I'm hearing, although the noise from the generator has been constant for the entire time we've had the RV and not gotten worse, so it seems unlikely that in the 1,000 hours and 3 years of run time a loose item wouldn't have let go by now. Manually turning the engine over I don't hear any funny noises from the engine or the generator part, but I'll look at it further.
With the generator out of the bus one of the things I'm going to do is apply Rockmat and sound deadening material to metal floor above the generator. That has nothing and produces a noticeable tin canning effect, which could be influencing things some.
I'm probably overthinking this, since the absolute worst case scenario is I could buy a portable generator and get power that way to deal with getting back home in case of a failure, and I'm addressing all of the most likely failure points and maintenance issues. But this is what I do and I try hard to make sure that we suffer no breakdowns or issues on our trips, which so far has been pretty successful.
tmyers
En-Route
Did you ha e to raide the front end of the bus to remove the generator? A d if so how high?
Sent from my SM-N970U using Tapatalk
Sent from my SM-N970U using Tapatalk
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I went ahead and ordered the parts I want to replace on the generator. Although the hoses look to be original, they are all in very good condition and are not showing any signs of leakage, marginal, etc., and it also looks like it would be a pain to change them. I haven't found any posts indicating that people have had issues with the hoses leaking. But issues that people have brought up are a bad thermostat and a bad coolant temperature sensor. So, I've ordered those (with of course a new thermostat gasket) and will be putting those on.
I also ordered the obvious necessary items of a valve cover gasket and a water pump belt, so those will be put on.
In my research, one disturbing fact that's come up is that the Quiet Diesel 7500s are known for throwing magnets on the generator side. This is apparently roughly a $5k repair and from looking at things it doesn't appear that this is 1) at all easily accessible 2) something you can really do much about for preventative maintenance. The root cause apparently comes down to a new type of magnet bonding that Onan used at that time which didn't work out very well. It's making me wonder if that is part of my noise issues I've been having, but seeing as I found two potential vibration sources as well as valves way out of adjustment make me think hopefully I will have it a bit quieter than it was before. Regardless, I'll test run the thing outside of the bus before I put it back in.
I also ordered the obvious necessary items of a valve cover gasket and a water pump belt, so those will be put on.
In my research, one disturbing fact that's come up is that the Quiet Diesel 7500s are known for throwing magnets on the generator side. This is apparently roughly a $5k repair and from looking at things it doesn't appear that this is 1) at all easily accessible 2) something you can really do much about for preventative maintenance. The root cause apparently comes down to a new type of magnet bonding that Onan used at that time which didn't work out very well. It's making me wonder if that is part of my noise issues I've been having, but seeing as I found two potential vibration sources as well as valves way out of adjustment make me think hopefully I will have it a bit quieter than it was before. Regardless, I'll test run the thing outside of the bus before I put it back in.
tmyers
En-Route
Cummins also recommends their blue antifreeze/coolant vs the yellow variety
Sent from my SM-N970U using Tapatalk
Sent from my SM-N970U using Tapatalk
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
That's good to know, I should look into that before refilling. It had yellow in it when I drained.
Cummins shipped my generator bits and those are supposed to be here tomorrow. New hoses and some new clamps and I should be able to get things back together probably sometime next week.
Last night my wife got home from work and we went right into tiling the toilet close, that should get done this week and the toilet reinstalled. I also got the 50 gallon water tank in place and am able to use the old water pump I replaced on the RV as a transfer pump, I just need a couple of fittings.
There are a lot of projects in different directions, but it'll all get done.
tmyers
En-Route
I have also read about a green antifreeze that is a short term solution, and an orange that is supposed to have a longer useful life
Sent from my SM-N970U using Tapatalk
Sent from my SM-N970U using Tapatalk
- Joined
- Jul 21, 2014
- Messages
- 9,770
- Location
- Broken Arrow, OK
- Display Name
Display name:
SoonerAviator
Most of the newer diesels use something like Cat ELC which is an "extended life coolant" and silicate-free. It's actually red in color. Good for something like 12K hours in OTR trucks.
tmyers
En-Route
Yes I think this is similar to what you are referencing. https://www.fleetguard.com/s/coolan...ite-free)&level4=Silicate Free&language=en_US
Sent from my SM-N970U using Tapatalk
Sent from my SM-N970U using Tapatalk
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I decided to just go ahead and put in the yellow (universal) coolant. I can change coolant regularly on this generator, and that's what was in there before. Given that coolant incompatibilities can cause issues and I found no issues with the cooling system when I took everything apart, that made the most sense.
The generator is back on the mount and I have everything completed on it. Well, "completed". I haven't put the outside panels on the generator and I want to run it before I do that. I need to throw oil in as well.
The water/methanol injection kit should arrive tomorrow, and that should be an easy enough install, but it will still take time to complete. I might get to that this weekend.
The generator is back on the mount and I have everything completed on it. Well, "completed". I haven't put the outside panels on the generator and I want to run it before I do that. I need to throw oil in as well.
The water/methanol injection kit should arrive tomorrow, and that should be an easy enough install, but it will still take time to complete. I might get to that this weekend.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Generator is all back together and ready to install. On the test run it seemed quieter and not rattling so much, so that's a good thing. The real test will be once it's inside the RV, but I think it's overall going to be better. No leaks that I was able to find, hopefully there's nothing I missed.
One of the items I had on my list was to look at why the lower alternator was wobbly. The accessory in that location on the engine (the first one that gets pulled by the serpentine belt) has always gotten beaten up, the rear mounting bolt specifically. Well in this case that one was beaten up but came off ok (I've had some really, really awful times getting that bolt off in the past) but the front ear on the 28si alternator had come off:
My working theory on this is that the harmonic dampener has always been bad on the engine as the silicone in it can dry out. They make a big deal about this on the bigger Cats where that can snap the crankshaft. On the little 3126 that doesn't seem to be as much of an issue, but I have a feeling that it's been causing issues on that accessory. I changed the dampener a couple of weeks ago, so we'll see if I can observe a difference once I get the engine back together and running.
The water/methanol injection is coming along nicely. I have the intake tube removed where I'm going to weld the bung in for the nozzle, got the controller mounted and all the wiring run, and it looks as though everything works. The only issue I seem to be having is that the indicator LED up front doesn't seem like it's working. I'll look into this further, if I have to replace the LED it's not too bad to do. I still have to mount the tank and pump, but in reading the instructions there's an optional in-line filter. This seems like a very good idea so I ordered that to get it coming.
There's a square tube that's part of the metal structure of the bus (the RV part, not part of the chassis) that's rusted through in the area of the generator. So, I will probably try to get that cleaned up and weld in some new angle iron to patch it up. While there I may find a few other areas that would benefit from a little welding while I have the generator out, but it's basically ready to go back in.
Not bad progress...
One of the items I had on my list was to look at why the lower alternator was wobbly. The accessory in that location on the engine (the first one that gets pulled by the serpentine belt) has always gotten beaten up, the rear mounting bolt specifically. Well in this case that one was beaten up but came off ok (I've had some really, really awful times getting that bolt off in the past) but the front ear on the 28si alternator had come off:
My working theory on this is that the harmonic dampener has always been bad on the engine as the silicone in it can dry out. They make a big deal about this on the bigger Cats where that can snap the crankshaft. On the little 3126 that doesn't seem to be as much of an issue, but I have a feeling that it's been causing issues on that accessory. I changed the dampener a couple of weeks ago, so we'll see if I can observe a difference once I get the engine back together and running.
The water/methanol injection is coming along nicely. I have the intake tube removed where I'm going to weld the bung in for the nozzle, got the controller mounted and all the wiring run, and it looks as though everything works. The only issue I seem to be having is that the indicator LED up front doesn't seem like it's working. I'll look into this further, if I have to replace the LED it's not too bad to do. I still have to mount the tank and pump, but in reading the instructions there's an optional in-line filter. This seems like a very good idea so I ordered that to get it coming.
There's a square tube that's part of the metal structure of the bus (the RV part, not part of the chassis) that's rusted through in the area of the generator. So, I will probably try to get that cleaned up and weld in some new angle iron to patch it up. While there I may find a few other areas that would benefit from a little welding while I have the generator out, but it's basically ready to go back in.
Not bad progress...
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
The generator is installed and the test run was a success. While it still has a couple of rattle noises (undoubtedly things I didn't find internally, probably buried deep in an inaccessible area), there's no doubt that it's quieter than it used to be. One big thing before is that you could be far away and there was no question that it was running. That's much less the case now. I had it running in the shop with both rooftop ACs on full blast, and was outside the shop helping my daughter with her dirt bike, and didn't notice the sound of the generator over the dirt bike.
Another fun thing is that since the new rooftop ACs are more efficient than the old ones, even on full blast they don't make the generator run as hard. So, more quiet.
An overall success. Now to wait for more parts to show up and keep on getting it back together.
Another fun thing is that since the new rooftop ACs are more efficient than the old ones, even on full blast they don't make the generator run as hard. So, more quiet.
An overall success. Now to wait for more parts to show up and keep on getting it back together.
tmyers
En-Route
What is your next trip, I know you told me but the memory fades. We are on Amish country in NE Ohio for a few days then heading to NC for the Grandfather Mountain Highland Games
Sent from my SM-N970U using Tapatalk
Sent from my SM-N970U using Tapatalk
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
I got the new alternator installed, it's running and has good voltage. On the test run, it was also immediately apparent that I was seeing less vibration from the accessories. That indicates to me that my theory about the harmonic balancer being bad was correct, and that it was good to replace it. I'll see if I can quantify this better in a video to post.
The water injection is almost done, all I have to do is install the intake pipe (I've got the bung welded in) and install the nozzle plus decide on my settings.
Our next trip will include mountains and hot temperatures, and so I had been thinking about adding a radiator mister system. There are a number of things I don't particularly like about the idea, and I think that I'm just going to go with the water injection for the moment. I can always turn up the volume of water for more cooling if need be, and I think that'll be the way to go.
The water injection is almost done, all I have to do is install the intake pipe (I've got the bung welded in) and install the nozzle plus decide on my settings.
Our next trip will include mountains and hot temperatures, and so I had been thinking about adding a radiator mister system. There are a number of things I don't particularly like about the idea, and I think that I'm just going to go with the water injection for the moment. I can always turn up the volume of water for more cooling if need be, and I think that'll be the way to go.
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
Last night I got to test drive the bus with all of the recent modifications and make sure everything seems to be working well. The test drive was successful. Notes:
The harmonic damper definitely seemed to have been bad. The engine actually feels smoother and the accessories (two alternators) don't vibrate like they used to. I'm betting this was always bad and it probably contributed to the bearing needing replaced and the accessories getting beat up like they were. On the bigger Cats (like C15s) replacing them is a more commonly discussed preventative maintenance item. Supposedly, those engines will snap crankshafts with a bad damper. It's not discussed on 3126/C7s much, but it definitely seems to have been important. With older vehicles, it seems like that's something that's often overlooked, but still important - they're there for a reason.
The new alternator charges just fine, so that's good.
The new rooftop AC units pump out plenty of cold air. We'll see how they do in the summer temps, but on the test drive last night they kept the bus plenty cool. Their quieter performance was also noticeable, mostly in the fact that the generator can now be heard more than previously. This confused me at first since the generator was very quiet inside the bus after the air spring modification, but then I realized what was happening and it made sense. The white noise from the old fan motors was enough to drown out more of the generator noise.
The generator is quieter, it's hard to say if it's smoother or not, but it's still loud by my opinion. I think the real test will be at some of the places we stay where we'll see how far away the generator can be heard from. It seems like it has less of a drone/resonance now than it did previously, which was part of the goal with the work performed. That one will be interesting to judge. I think in the end, the really high end RVs that put the generator in a heavily insulated bay of its own are the only real way to get the thing "silent".
But on that note, I had put both sound deadening (Dynamat) and some foam sound deadening under the floor above the generator. The purpose of this was to try to reduce/eliminate the tin-canning effect of the solid steel floor above the generator. Good for a firewall, bad for noise (especially road noise). Initial impressions on the test drive were that the ride was overall quieter, which is a good thing. We'll see how my impressions seem as I continue to drive it.
Lastly, the water injection seems to work, although I'll need to get some more driving time to see just how well it works. The goal behind it more than anything is to reduce induction air temperatures and in so doing also reduce the pre-heating of air before it gets to fans on long upgrades (an inherent problem in this setup). Last night's drive wasn't particularly hot (mid 80s) and we don't have challenging hills in Kansas to test this on, but I could see that both 1) the system worked and 2) it did seem like IATs were down on the order of 30F when it was working. I changed the settings a bit on the controller and when we're out where the system gets a real challenge we'll see how the system works. On long uphills I tend to run at "20 squared" - 2,000 RPM and 20 PSI boost - as above that seems to be where the temperatures just get out of control. Around here it's hard to end up with that sot of a consistent load, and it also doesn't help that my engine gauges have a lag being over Bluetooth and the ECU connection. I didn't notice a significant change in EGTs, although injecting both water and methanol can impact that. The methanol is fuel (richens the mixture, should raise EGTs), the water should cool EGTs, and by cooling the IAT charge that both can increase the air density for the same boost level and also change the injection advance the engine is doing, since it seems to retard injection timing with IAT to impact NOx emissions.
As usual, there's a lot to test on the next trip.
The harmonic damper definitely seemed to have been bad. The engine actually feels smoother and the accessories (two alternators) don't vibrate like they used to. I'm betting this was always bad and it probably contributed to the bearing needing replaced and the accessories getting beat up like they were. On the bigger Cats (like C15s) replacing them is a more commonly discussed preventative maintenance item. Supposedly, those engines will snap crankshafts with a bad damper. It's not discussed on 3126/C7s much, but it definitely seems to have been important. With older vehicles, it seems like that's something that's often overlooked, but still important - they're there for a reason.
The new alternator charges just fine, so that's good.
The new rooftop AC units pump out plenty of cold air. We'll see how they do in the summer temps, but on the test drive last night they kept the bus plenty cool. Their quieter performance was also noticeable, mostly in the fact that the generator can now be heard more than previously. This confused me at first since the generator was very quiet inside the bus after the air spring modification, but then I realized what was happening and it made sense. The white noise from the old fan motors was enough to drown out more of the generator noise.
The generator is quieter, it's hard to say if it's smoother or not, but it's still loud by my opinion. I think the real test will be at some of the places we stay where we'll see how far away the generator can be heard from. It seems like it has less of a drone/resonance now than it did previously, which was part of the goal with the work performed. That one will be interesting to judge. I think in the end, the really high end RVs that put the generator in a heavily insulated bay of its own are the only real way to get the thing "silent".
But on that note, I had put both sound deadening (Dynamat) and some foam sound deadening under the floor above the generator. The purpose of this was to try to reduce/eliminate the tin-canning effect of the solid steel floor above the generator. Good for a firewall, bad for noise (especially road noise). Initial impressions on the test drive were that the ride was overall quieter, which is a good thing. We'll see how my impressions seem as I continue to drive it.
Lastly, the water injection seems to work, although I'll need to get some more driving time to see just how well it works. The goal behind it more than anything is to reduce induction air temperatures and in so doing also reduce the pre-heating of air before it gets to fans on long upgrades (an inherent problem in this setup). Last night's drive wasn't particularly hot (mid 80s) and we don't have challenging hills in Kansas to test this on, but I could see that both 1) the system worked and 2) it did seem like IATs were down on the order of 30F when it was working. I changed the settings a bit on the controller and when we're out where the system gets a real challenge we'll see how the system works. On long uphills I tend to run at "20 squared" - 2,000 RPM and 20 PSI boost - as above that seems to be where the temperatures just get out of control. Around here it's hard to end up with that sot of a consistent load, and it also doesn't help that my engine gauges have a lag being over Bluetooth and the ECU connection. I didn't notice a significant change in EGTs, although injecting both water and methanol can impact that. The methanol is fuel (richens the mixture, should raise EGTs), the water should cool EGTs, and by cooling the IAT charge that both can increase the air density for the same boost level and also change the injection advance the engine is doing, since it seems to retard injection timing with IAT to impact NOx emissions.
As usual, there's a lot to test on the next trip.
charheep
Cleared for Takeoff
Do you worry about heat building up for the generator, now that you are sealing/insulating it more?
Ted
The pilot formerly known as Twin Engine Ted
- Joined
- Oct 9, 2007
- Messages
- 30,005
- Display Name
Display name:
iFlyNothing
No. Nothing that I have done has actually increased the thermal insulation or restricted airflow. The airflow is out of the bottom. There's a cooling fan in front that sucks air in, pressurizes the "cold" side of the generator, and then goes through the radiator and out the back on the "hot" side (with the exhaust, muffler, etc.) then out the bottom. Nothing I've done impacts that airflow.