Tips On Troubleshooting Oil Leak

Snowmass said:
Modern auto engines use lots of aluminum just like aero engines and use identical lubrication systems. Of course it's not the standard way of sealing in aircraft engines because aircraft engines use backward technology.
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Backward or not, until your “modern auto engines” require a regulatory certificate to be produced and require federally certified individuals to operate and maintain it, your whole point is moot. Now apply that point to E/AB aircraft and you can have your discussion all day long. Regardless, I can show you more OEM/FAA references to NOT use RTV than to use RTV. It is what it is. What's ironic is that I'm having this conversation with an aero engineer.
Snowmass said:
I will bet anyone $1000 or $10,000 or more if they can show any damage to my IO-520 due to sealing the pushrod tubes with RTV. Open up your ossified minds.
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Depends on how you define “damaged.” It may not have corrosion as of yet or pieces of RTV floating in the oil system, but in my opinion it pretty much cratered in its current RTV’d condition. With the RTV it’s unairworthy on several levels which I would considered damaged without anything broke. I’ll take that $10k in bitcoin.;)

And just to add, here is a classic example from another thread on aircraft owners not maintaining the airworthiness of their aircraft per 91.403. That is unless you are just BSing us and you use the proper sealants. One poster on that other thread mentioned most PoA’ers are simply full of BS when making comments like yours. :rolleyes:
 
Checkout_my_Six said:
If you have to go all redneck & Jerry rigging stuff....go with ProSeal on the "outside" of the engine (and do a neat job by masking off the area you're sealing).
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This was my last resort and it worked.
 

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Lon Stratton said:
This was my last resort and it worked.
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Do you run oil samples? When was the last time you did a static RPM check?

Only reason I ask is because I've had a handful of engines come in with this sort of job on it. The case halves were fretting. In one case I discovered that the engine was "overhauled" in the field and the "mechanic" did not use new through studs. So when he torqued the case (not IAW the proper SB and so not in the proper sequence) the load on the studs was improper. The engine made metal from the case AND the journals. Unfortunately, the guy ended up having to overhaul again. We convinced him to have it done at a reputable shop.

If this is holding for you, I'm pleased and hope you get many more hours out of it. This is much different than applying sealants in your valve train...as some seem to advocate
 
Another oil leak source is often the pressure screen housing and rocker covers where guys have over-tightened the bolts/screws. Its easy to do, especially rocker covers that use silicone gaskets. Don’t over-tighten. Check the flanges on a known flat surface to see if any of the screw tabs have been bent.
 
Der Fliegermeister said:
Do you run oil samples? When was the last time you did a static RPM check?

Only reason I ask is because I've had a handful of engines come in with this sort of job on it. The case halves were fretting. In one case I discovered that the engine was "overhauled" in the field and the "mechanic" did not use new through studs. So when he torqued the case (not IAW the proper SB and so not in the proper sequence) the load on the studs was improper. The engine made metal from the case AND the journals. Unfortunately, the guy ended up having to overhaul again. We convinced him to have it done at a reputable shop.

If this is holding for you, I'm pleased and hope you get many more hours out of it. This is much different than applying sealants in your valve train...as some seem to advocate
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The engine was overhauled in 2000 and I have almost 1800 hours on it. I've done oil analysis since day one and change it every 35 hours or 6 months. All engine data is uploaded to Savvy Analysis. Never removed a cylinder. I use a quart every 9 hours. This was the result of chasing an oil leak that was appearing on the oil filler door hinge as a few drops. After a couple hours of flight, there would be a thin streak of oil that made its way to where the cowling met the fuselage and turn into a fine mist that ended up on my window. Maddening! Since I was so close to TBO, we tried it as a last resort. And as mentioned, it stopped that particular oil problem. I still have a little bit of spray in the engine compartment, but considering the age and usage, I'm fine with it.
 
Snowmass said:
Not one of you finger waggers has answered why today's billions of automotive engines deliberately use RTV silicon for engine sealing. I am waiting.
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Because the interfaces are designed for it to prevent extrusion and escape of the sealant.

Did you know that we use silicone gaskets on rocker covers now?

Again, auto stuff and technology are different. Do you use DOT-3 aircraft brake fluid in your aircraft brake system? How about tractor hydraulic fluid in your 210's gear system? Those would be expensive mistakes.

Snowmass said:
Progress does not result from doing things the same old way and modern auto engines are light years ahead of our 1935 TCM technology. Maybe some of you are too old to accept modern technology. I remember a long time ago when the FAA mandated primitive casein wood glues on wooden airplanes many mechanics used modern Weldwood glue instead. Were mechanics smarter then?
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History matters: Casein wood glues were superseded by urea-formaldehyde glues by 1939. That's 82 years ago. Nobody was using casein for aircraft after that. Aerolite was the urea-formaldehyde go-to stuff for homebuilders for decades, and Bellanca and Mooney both used it in the assembly of their wood wings. Weldwood glue is urea-formaldehyde that has been filled with powdered wood to make it easier to apply and to fill gaps left by amateur woodworkers, and it isn't as strong or fungus-resistant as its ancestor, Aerolite. If the homebuilder didn't use Aerolite he used Resorcinol glue, a formaldehyde glue that is still used in plywood, including aircraft plywood, since it is superior to epoxy for that. Better UV resistance. Epoxy pretty much took over the homebuilding glue market, and I used the early stuff almost 50 years ago and got my immune system all outraged over it, causing allergies. I have to be careful with the stuff now. We used epoxies for fiberglass repairs on TC aircraft; it sticks much better than the original polyester resins. And that is in accordance with AC43.13-214A, an FAA-approved document.

You seem to be under the impression that we are still using all the 1940s stuff. In some cases, that's true. Cleveland still supplies main wheels with felt seals, and that's because the aircraft axles were designed for them, not for nitrile. New nosewheels come with nitrile seals, though. They're a different mechanical setup. That Continental list of approved lubricants and sealants is full of thoroughly modern products. Loctite sealants are among them, sometimes special stuff that is hard to find in any hardware store and even some industrial suppliers won't have it in stock. The O-rings found in the restart Cessna fuel injection systems are of modern compositions, far superior to the old Buna N. The airframes are primed with epoxy primers (and I used those when I painted airplanes more than 20 years ago. They weren't in common use in the auto industry at that time). Urethane topcoats are common, and we used them before the automakers did. We used a lot of modern chemicals in the shop. You're not an A&P so you don't know what a good shop keeps in its stores. Things have changed a lot since your airplane was built. On the other hand, I find it strange that you still insist on using a generator instead of an alternator, and a wet vacuum pump, too. And incandescent lighting. All of those are far inferior to the new stuff.
 
Hey...hold on now, no need to start insults against those of us who still run generators and wet vacuum pumps...I fly a classic airplane...the generator is more than adequate for the job since all the avionics are no longer tube type...the wet vacuum pump works just fine. :)

With that being said, I do not use rtv on internal parts of my aircraft engines.

Carry on...:)
 
Lon Stratton said:
The engine was overhauled in 2000 and I have almost 1800 hours on it. I've done oil analysis since day one and change it every 35 hours or 6 months. All engine data is uploaded to Savvy Analysis. Never removed a cylinder. I use a quart every 9 hours. This was the result of chasing an oil leak that was appearing on the oil filler door hinge as a few drops. After a couple hours of flight, there would be a thin streak of oil that made its way to where the cowling met the fuselage and turn into a fine mist that ended up on my window. Maddening! Since I was so close to TBO, we tried it as a last resort. And as mentioned, it stopped that particular oil problem. I still have a little bit of spray in the engine compartment, but considering the age and usage, I'm fine with it.
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Hey 1800 hours is pretty darn good for a Continental...especially with no top end work.

I think you're approaching the ongoing maintenance with the right attitude and attention to the machine. It'll let you know when it needs to be overhauled.

I'm running approximately 1 quart every 8-10 hours on an IO-520-MB in a 310R that's past TBO. It'll be ready for an overhaul in the next 100 hours or so.
 
Doug Reid said:
Hey...hold on now, no need to start insults against those of us who still run generators and wet vacuum pumps...I fly a classic airplane...the generator is more than adequate for the job since all the avionics are no longer tube type...the wet vacuum pump works just fine. :)

With that being said, I do not use rtv on internal parts of my aircraft engines.

Carry on...:)
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The generator has a hard time keeping up at night. Typically 35 amps, sometimes only 20 or 25, so the wattage is (at 14V) between 280 and 490. And that's at a lot more than idle RPM. Most don't generate at all below 1200 engine RPM. Some landing lights, like the 4522, draw 250 watts each. Others are 100 apiece. Add in the nav lights and anti-collision beacon of some sort, and we're in trouble long before we take off. If we replaced all of them with LEDs we'd be OK. A zenon strobe draws about 2 amps, so that's not too bad. The alternator generates plenty at idle, and buckets at cruise. And it's half the weight and the brushes are cheap and will usually go 1000 hours. Generator parts are getting harder to find. And a new gear-driven generator? Good luck with that.

The wet vacuum pump can last a long time, but the air-oil separator doesn't get all the oil and it messes up the belly. Depending on the engine, the dry pump can last 1200 hours or more, and if one is smart and buys a Tempest or Rapco pump, 100-hour inspection of the pump's vane wear after the 500-hour mark will let you know when it needs changing. Almost no risk of inflight failure that way. Takes five minutes to check. Airborne, AFAIK, still doesn't have that feature.
 
UPDATE:

I updated our life insurance policies last night just in case. This morning I took off the bottom cowl and cleaned it all up. The wife hopped in a did a few laps around the pattern. Said it flew weird without any cowlings on??? Whatever, she's kinda weird that way. When the windshield had too much oil to see out the front she pulled the power, cut the mixture and side slipped it all the way down and straight into to the hangar. We cleaned the engine bay again. Put the cowls back on, closed the cowl flaps, inserted the nose plugs and then squirted 163 tubes of RTV inside until it finally started coming out the top oil fill door. Solved. BOO YAH!!!

Kidding of course. That was for @Tantalum because he loves Skylanes and @Rgbeard because he loves my husband/wife flying stories LOL.

Seriously....I did take off the bottom cowl and clean it all really good. For the push rod tube theory, the best I could see was some older oil around the pilot side front cylinder push rod tubes. But that really looked like it was from long ago spilled oil since its pretty much below the oil fill cap. Same thing around the dipstick tube. What little oil there looked old. It was clamped down really good too. Not a drop around the quick drain nor the other fitting going into the pan (oil temp or pressure?). So it really seemed like this leak was in the back by the firewall.

The thing that kept bothering me was the amount of oil that had collected on top of the strut. Like a mini reservoir. So we decided to start with one quick run up with all cowls off. No more than 60 seconds. Before startup we swept up really good to make sure nothing would get sucked into the carb since there was no filter. I had our purple K extinguisher nearby even though we just used dried shop rags (no solvents or cleaners yet). Both tires chocked and the parking brake on.

She fired it up and nothing. I came up from the back and peeked around. About then I saw oil really gushing out and by the time I raised my hand for her to cut the engine the firewall was drenched again and the windshield was completely covered in oil. Lets hope that was her first and last time she (or I) see that again!!! Unfortunately I didn't spot the exact the location on that run. So we toweled it off again. Once again, not a new drop anywhere forward.

Second run, after about 30sec and oil pressure up nice and good I had her bump the rpm maybe 1,300 instead of 1,000. I spotted it coming out what looked like the bottom of the alternator drive pulley shaft. Its started gushing pretty good and we stopped the engine again. After it was shut down and safe I started wiping in this area and notice what appears to be a sleeve (or ???) that is loose around the pulley shaft. I can move it with my fingers. See the attached image. Has a red paint stripe/band towards the firewall side.

Definitely not going to fly it anywhere!!! No AP shops open today. That space seems pretty tight to be able to remove that plate and assembly. My eye thinks I can see how it might be removed...if there is space. So that's what we know right now. It is definitely not a slow leak or safe to fly. Typical, was the nicest flying morning in the last 2 weeks.

We did a short 3rd run and although it had plenty of oil and the same typical oil pressure (indicated) it didn't leak. So maybe the oil is low enough now to not spill out of there. It should be around 8qts. I cleaned it all up, parked it and tipped the tail to the same angle as when we first checked oil. Will check oil tomorrow to see how much we actually lost. I am guessing about 1/4...1/3qt.

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Sinistar said:
That was for @Tantalum because he loves Skylanes
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But it's like disliking a friend's dog. If it flies (or is a dog) it's automatically got a place in my heart.. even if it's a yappy chihuahua or a 182!

I still hold the 190/195 as the epitome of a what single engine ga should look like!!
 
Looks like a bearing for a drive pulley worked its way out...but why and what about the shaft where it engages internally to the engine. Good catch!
 
455 Bravo Uniform said:
Looks like a bearing for a drive pulley worked its way out...but why and what about the shaft where it engages internally to the engine. Good catch!
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I have learned from a another awesome POA'er that it is called a garlock seal. Maybe the bearing is still in place? Maybe its irrelevant. Back to the main question being what caused it to migrate or work out. I know it wasn't seized, at least not yet, as the alternator was working fine right up until I landed it. Funny all that oil didn't at least cause the alternator belt to slip. I'm thinking the bill ain't gonna be so funny though :(
 
Sinistar said:
UPDATE:

I updated our life insurance policies last night just in case. This morning I took off the bottom cowl and cleaned it all up. The wife hopped in a did a few laps around the pattern. Said it flew weird without any cowlings on??? Whatever, she's kinda weird that way. When the windshield had too much oil to see out the front she pulled the power, cut the mixture and side slipped it all the way down and straight into to the hangar. We cleaned the engine bay again. Put the cowls back on, closed the cowl flaps, inserted the nose plugs and then squirted 163 tubes of RTV inside until it finally started coming out the top oil fill door. Solved. BOO YAH!!!

Kidding of course. That was for @Tantalum because he loves Skylanes and @Rgbeard because he loves my husband/wife flying stories LOL.

Seriously....I did take off the bottom cowl and clean it all really good. For the push rod tube theory, the best I could see was some older oil around the pilot side front cylinder push rod tubes. But that really looked like it was from long ago spilled oil since its pretty much below the oil fill cap. Same thing around the dipstick tube. What little oil there looked old. It was clamped down really good too. Not a drop around the quick drain nor the other fitting going into the pan (oil temp or pressure?). So it really seemed like this leak was in the back by the firewall.

The thing that kept bothering me was the amount of oil that had collected on top of the strut. Like a mini reservoir. So we decided to start with one quick run up with all cowls off. No more than 60 seconds. Before startup we swept up really good to make sure nothing would get sucked into the carb since there was no filter. I had our purple K extinguisher nearby even though we just used dried shop rags (no solvents or cleaners yet). Both tires chocked and the parking brake on.

She fired it up and nothing. I came up from the back and peeked around. About then I saw oil really gushing out and by the time I raised my hand for her to cut the engine the firewall was drenched again and the windshield was completely covered in oil. Lets hope that was her first and last time she (or I) see that again!!! Unfortunately I didn't spot the exact the location on that run. So we toweled it off again. Once again, not a new drop anywhere forward.

Second run, after about 30sec and oil pressure up nice and good I had her bump the rpm maybe 1,300 instead of 1,000. I spotted it coming out what looked like the bottom of the alternator drive pulley shaft. Its started gushing pretty good and we stopped the engine again. After it was shut down and safe I started wiping in this area and notice what appears to be a sleeve (or ???) that is loose around the pulley shaft. I can move it with my fingers. See the attached image. Has a red paint stripe/band towards the firewall side.

Definitely not going to fly it anywhere!!! No AP shops open today. That space seems pretty tight to be able to remove that plate and assembly. My eye thinks I can see how it might be removed...if there is space. So that's what we know right now. It is definitely not a slow leak or safe to fly. Typical, was the nicest flying morning in the last 2 weeks.

We did a short 3rd run and although it had plenty of oil and the same typical oil pressure (indicated) it didn't leak. So maybe the oil is low enough now to not spill out of there. It should be around 8qts. I cleaned it all up, parked it and tipped the tail to the same angle as when we first checked oil. Will check oil tomorrow to see how much we actually lost. I am guessing about 1/4...1/3qt.

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Definitely RTV it back in. A 16 oz hammer will help...

Do not do this. Just laugh.
 
Thanks for the story! It was a fun read and I was captivated.

seriously, I believe you’ll find it’s a simple alternator oil seal. But I don’t have experience with your engine.

wishing you all the best. This stuff, once fixed, seems simple in the rear-view mirror
 
Sinistar said:
Back to the main question being what caused it to migrate or work out. I know it wasn't seized, at least not yet,
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Warning: Not an A&P.
But my auto experience has been that a plugged crankcase vent can push a seal out like that. They are typically a light press fit into the bore. I would assume that it is also possible that a slightly under sized seal or damaged bore would let this happen, but that is speculation - I've never seen that happen.
In a car, I would consider Loctite to hold it in place...

I wouldn't recommend using RTV to replace the seal.
 
I don't work on many new vehicles, but everything nowadays is O rings, no RTV!

Was the suggestion to keep push rod tubes from leaking to use RTV to prevent oil from getting to them ? If so, how does the oil drain back to the crankcase?
 
Sinistar said:
Back to the main question being what caused it to migrate or work out.
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Most failures like that I've seen were usually prior installation issues, e.g., seal was cocked, over driven, etc. Most times those seals fail at the shaft interface due to wear at either side or if a spring type seal the spring fails reducing the seal lip preload.
Sinistar said:
I'm thinking the bill ain't gonna be so funny though
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FYI: It shouldn't be too bad. Pull the pulley and change the seal. However, I'll defer to your mechanic as some like to remove the seal housing to ensure the new seal is installed square. Unless there's something wrong with the seal recess it should not require you to remortgage the house to get it fixed.
 
That pulley looks like the shaft is out of alignment, which would indicate bearing failure. I once encountered that in an O-470, and it was the balls that had fallen out of the bearing and into the accessory case where they luckily didn't get between any gears and cause catastrophic failure. I'd get that looked at before you ever start that engine again. That housing has the starter drive in it and those bearings take a lot of force during starting.
 
While it's apart I'd definitely make a good inspection of the housing and measure the bore. Maybe even dye pen it. Often the reason seals pop out like that is the bore is cracked or otherwise damaged. But looking at the red polyacrylate stripe, it just looks to me like it wasn't fully seated when installed.
 
Wagondriver said:
I don't work on many new vehicles, but everything nowadays is O rings, no RTV!

Was the suggestion to keep push rod tubes from leaking to use RTV to prevent oil from getting to them ? If so, how does the oil drain back to the crankcase?
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How would you seal an oil pan with an O-ring? Here it's RTV.

The RTV does NOT keep oil from the oil tubes but it keeps the oil from reaching the upper seals.

The small bead of of RTV just goes in the resulting channel between EXTERIOR of the oil tubes and the interior of the cylinder head hole on top of the washer that rests against those white silicon rubber donut seals. The problem with TCM design on the upper pushrod tubes is you don't get a lot of radial squeeze on the donuts. The bottom seal is excellent as the seal assembly goes into a long tapered hole.
 
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and this why folks you should always fly low wing

sorry Brad, I had to lol.

on a serious note, hope its something simple
 
I had my cowling off yesterday. TSIO520D, I replaced a cracked cylinder on it at last annual, about 100 hours since then. I used NO RTV on it, nor on the cylinder that was replaced the year before. Dry as a bone, no oil anywhere.
The only RTV I have used is on the exhaust gaskets, to help hold them in place while fitting the exhaust.
 
Snowmass said:
Not one of you finger waggers has answered why today's billions of automotive engines deliberately use RTV silicon for engine sealing. I am waiting.

Progress does not result from doing things the same old way and modern auto engines are light years ahead of our 1935 TCM technology. Maybe some of you are too old to accept modern technology. I remember a long time ago when the FAA mandated primitive casein wood glues on wooden airplanes many mechanics used modern Weldwood glue instead. Were mechanics smarter then?
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Those automotive engines have been designed and engineered to utilize RTV/silicone sealants. The engine mating surfaces have the proper clearances for accepting the desired amount of sealant, which is accurately applied by robots. Predictable repeatability insures it is properly located and that no excess sealant is deposited.

None of the above conditions are present in aviation engines, which means that manual overapplication and the release of sealants into the engine internals is a good possibility. There is no way to confirm this has not occurred during assembly.

I would expect any engineer with basic knowledge of the respective engine technologies to be cognizant of the limitations the older technology has in accepting deviations to assembly methods, especially if the engine manufacturers specifically forbid those deviations.

Apparently that doesn't include you.
 
When I read letters like this I don't know whether tp laugh or cry. Tell me EXACTLY what the bead of RTV around the push rod tube is going to do to harm the engine. Suppose some RTV gets into the oil pan in which case it would appear in the oil filtering screen which it has not. The lubrication system of automotive engine and my IO-520A is identical. The real problem is your resistance to change. A common affliction which has so often held back human progress.

BTW, when a mechanic installs the oil pan after a repair he uses RTV per the shop manual and most mechanics are not robots.

This is getting boring so no more replies.
 
Snowmass said:
When I read letters like this I don't know whether tp laugh or cry. Tell me EXACTLY what the bead of RTV around the push rod tube is going to do to harm the engine. Suppose some RTV gets into the oil pan in which case it would appear in the oil filtering screen which it has not. The lubrication system of automotive engine and my IO-520A is identical. The real problem is your resistance to change. A common affliction which has so often held back human progress.

BTW, when a mechanic installs the oil pan after a repair he uses RTV per the shop manual and most mechanics are not robots.
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Once again, cars are not airplanes. Escaped RTV from an oil pan doesn't cause a crash that kills four people. Remember that.

The thin edges of RTV smears break off and slither through the oil pickup screens. Most of those screens are coarse enough to let that happen. If they're fine screens, enough small bits will obstruct it altogether. And when RTV goes through an oil pump, that pump is easily damaged. The clearances in it are extremely small and the RTV forces things apart.

For some years I was the foreman in an air brake component remanufacturing facility. One of the major causes of warranty claims on compressors was RTV. Some mechanics would use it everywhere on gaskets, and since many compressors are fed their oil from the engine's pressure system through a hole on the compressor's the mounting flange, the RTV would extrude into that hole, break free, and get forced into the smaller feed holes in the main bearings, blocking all oil flow. Instant death for the compressor, which would sometimes completely grenade into many pieces and blow a lot of engine oil overboard. Could kill the entire engine on that truck or piece of heavy equipment. A little bit of RTV. Such handy stuff. Some mechanics also used it as a pipe sealant, and it wrecked a lot of control valves that way. Failed brake control valves are no joke in a big truck on a busy freeway.

Maybe you didn't read the article about the aircraft engine that blew a cylinder off because RTV ended up on the mounting flange, where it allowed the cylinder to move in and out a tiny bit, hammering away at the studs until they failed. There are so many possibilities for unintended consequences in this aviation maintenance business, possibilities not always obvious to the mechanic but learned the hard way by some people. The resulting accidents are analyzed by the engine manufacturers, which is why they come out with lists of approved sealants.

Why some people can't defer to exponentially greater experience is beyond me.
 
UPDATE:

Finally had some time to just poke around and look at things. Just doing more recon to give the mechanic as much info as possible. Things I learned:

1. The alternator drive pulley bolt is indeed tight. Placing a wrench on it and turning it turns the alternator belt and all the way through motor and turns the prop. Doesn't mean there isn't something wrong inside but was nice to know it wasn't totally sheared or snapped. Then again the alternator was making electrons during the last flight so not a big surprise.

2. I didn't have a very good mirror but I used what I had and along with a good bright LED light and some crude cell phone pictures, I don't see any obvious cracks on the adapter plate, especially around the seal location. The bottom was the hardest to examine while still installed. If there are cracks they will be very small (which is still a crack).

3. Looking at the alternator belt I noticed a inline offset from the alternator pulley to the drive pulley. Actually about one belt width. Put another way, the drive pulley seems about 1 belt width too close to the firewall. I suppose its not enough to make the belt walk off but also seems wrong?

4. Someone else commented on the pulley shaft seeming to sit "low". I guess that could be true. I started my phone in video mode zoomed on the pulley at a side level. I then walked the prop through one revolution. Looking at the video I don't see it "wobbling" or "precessing". Maybe if anything if it is indeed loose it is bound sideways with all the belt tension.

5. With the pulley so close to the firewall I started wondering of the pulley shaft was loose? So I took my hands and pulled the pulley towards the motor (away from the firewall). It moved a bit more than half the drive belt width! I could then push it back out again. So the entire pulley seems to be able to move in/out a bit. I have no clue if this normal. I think there is a retaining clip on the back side of the housing. Maybe this has popped or or something? Or maybe it is designed to move in / out a bit.

Through the help a awesome POA'er :) I now have a diagram which is really helping me understand what my mechanic already knows. I have two mechanics in contact but both are on fields about 15min flight away. I will not fly it like this. I think my next step is to remove the pulley and adapter faceplate to get a look inside. From what I see I believe I can do this with no risk of parts falling inside. One AP already asked me to do this. The other was leaning this way as well. Ideally I can get these parts off, order the oil seal, cover gasket, clip, small o-ring and have the shop press them in in advance before driving out.

My next little mystery to keep things moving along is all about the pulley nut:

Q1. Is it standard righty tighty or opposite?
Q2. What do I do hold the motor side when I loosen it? Is it as simple as a 2x4 under the prop (like pinning a mower blade to remove its bolt). That sure seems wrong or too easy LOL!

Thanks for all the help so far. Plus I am learning about RTV :)
 
Stewartb said:
Another oil leak source is often the pressure screen housing and rocker covers where guys have over-tightened the bolts/screws. Its easy to do, especially rocker covers that use silicone gaskets. Don’t over-tighten. Check the flanges on a known flat surface to see if any of the screw tabs have been bent.
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Exactly what happened on my 180. Found a good used one on eBay for 40 bucks.
 
Snowmass said:
BTW, when a mechanic installs the oil pan after a repair he uses RTV
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I don't, but whatever.

Snowmass said:
The real problem is your resistance to change.
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That should read: resistance to losing your assets and your freedom when a box of 12 people that don't know anything about aviation maintenance convict you in a wrongful death/ criminal negligence suit.

You may be willing to go rogue on your maintenance practices because "the FAA and everyone else is an idiot compared to THIS engineer" (who earned an engineering degree, what...60 years ago?) but those of us with something to lose aren't going to jump on the bandwagon of a progressive carpet bagger toting the values of ignoring regulations and manufacturer's specifications for our paying customers.

I'm glad you have to had any problems. I really am. But I'm not going to take the risk. It seems the vast majority of us here won't.

The only thing I'm nervous about for you specifically is that when you or your posterity try to sell your airplane(s) when you're gone and the next buyer has a competent inspection done, the offer is going to be insulting to you/them.
 
UPDATE:

There are basically (2) camps when it comes to AP's that I have contacted.

The minority (1) recommended using a sealant (not RTV) and pushing the oil seal back in for the quick flight to his home base. That was very tempting. But my gut and my wife's are both twinging on this one. Probably woulda worked and been fixed by now :( But also might have grenaded. So not going that route.

The consensus camp is to pull the entire starter adapter and have it serviced. Lots of reading confirms this is one of Continental's sore spots. Thanks to diagrams from members here I think I understand about 90% of this. A very highly recommended AP suggested I pull it myself, have it serviced and he will help with the re-install provided no other problems. Time to get the hands dirty. I should also mention I work pretty slowly on this stuff because I am worried.

So last night I disconnected the battery. Pulled the starter. All the starter bearings are present and it still seems connected within the adapter (doesn't spin freely) so that is a nice sign but then again I already knew since I never heard the start spinning freely.

I released the alternator belt tension and got that out of the way. With no tension and the oil seal free (not the bearing) I think the alternator shaft is wobbling or I should say I can move it up and down and side to side...a little bit. Once again, hand propping forward spins the alternator drive pulley. And using a wrench on the pulley turns the prop.

It must be an old style adapter as I can move the prop backwards. I don't move it very much in that direction, about 1/30th of turn. I guess the new starter adapters will not allow turning it backwards.

Then the fun part, all the adapters nuts (2) and bolts (6). Ironically I found one empty hole...a upper (long) bolt was not even there!! I kept all parts in a box and will double check to tonight. I thought I had them all out but there was one more behind the little timing indicator thingy. Once that was out I gave it a very, very light tap with a 2x4 and hammer knocked it loose since it wouldn't pull free just by hand and I couldn't get a small screwdriver under an edge. So I was able to break it away from the motor. It almost clears the 2 studs before the alternator pulley front bolt starts to hit the firewall. It was getting dark and the moths were swarming my monster LED worklight. Note so self, work with hangar door closed when it starts getting dark in the summer LOL.

So I sit at the part the concerns me the most. Can I get it out without pulling the motor? I will focus on this over the next night or two. I have seen that some people have needed to pull the two studs. Not much room there for the old trick to remove them but maybe doable. I am also looking for something non metal to pry both sides away. Maybe like a plastic or delrin pry tool? I only have to move it about 3/4" to clear the two studs. That would then let me rotate it a bit to try other things. But I have no clue if that will be enough to get it to disengage from the crankshaft.

Only other comment is that I "slowly" moved the adapter and I have the plane's nose tipped up kinda high. I have not seen anything fall "up" from the adapter into the motor. Doesn't mean it hasn't already happened. Just that I didn't see anything during that movement.

Wish me luck on pulling it without pulling the motor. If I just knew how much clearance I need I would know if there is hope or not. Gonna hit the engine manual tonight and see if that will give it away.

No fun watching the nice evenings roll by. Busted knuckles are better than a engine out.
 
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There is "pulling the motor" and there is "pulling a couple mounts to let the motor move an inch" (watch out for things like carb linkages, exhaust systems, etc.)
But, I ain't no A&P so you will probably die if you listen to me.
 
Capt. Geoffrey Thorpe said:
There is "pulling the motor" and there is "pulling a couple mounts to let the motor move an inch" (watch out for things like carb linkages, exhaust systems, etc.)
But, I ain't no A&P so you will probably die if you listen to me.
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That engine is on a bed mount. You'd have to undo all four mounts, pick the engine up with a hoist and move it forward. And then the engine control cables would fight that. Fuel hoses, too.

I would find some way of grabbing that pulley and getting the retaining nut off. If it's a spoked pulley or has holes in it, I would take a couple of feet of 1/4" flat bar, inch or inch and a half wide, and drill a couple of 3/8" holes in the right places and put two 3/8" bolts in the holes with a nut on each side of the bar. Snug them up and stick the bolts through the pulley holes and wrench away. Or weld a couple of pins on the bar. Whatever. Could also use a Vise-Grip chain wrench in the pulley groove, but that has the risk of scarring the groove, which would eat belts up sooner. Maybe cut up an old belt and put that in the groove and clamp the chain wrench over it.

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As you guys just said, just not enough room :(.

I think I needed maybe just 1". I did get it past the two studs. I have it far enough out that it is no longer engaged with the crank. But I also pretty much hit the edge of my comfort zone. We have a engine hoist stagged and ready. Scheduled to work with AP tomorrow evening. He said he's done several of these. I think the rear mount bolts come all the way out. Fronts get loosened. Lift is used. Some nudging, etc.

Thanks for all the help and suggestions so far. Still more to this journey!
 
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