Lost my vacuum pump, severe VMC day

Kiddo's Driver

Kiddo's Driver

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Jim
I lost my vacuum pump yesterday in severe VMC. The spinning DG was distracting, so I hung a wash cloth over it. Other than that it was a non event. I would hate to have that happen when in IMC.

Stupid me, it never occurred to me to use the AHRS/Synthetic Vision feature on my iPad/Stratus 2s.
https://www.foreflight.com/products/foreflight-mobile/synthetic-vision/

It would have been a great time to play with it.

I'll post the vacuum pump model, and years & tac hours once I look them up.

Edit: part number overhauled Rspco 215CC, 12.5 years, 400 hours.

Jim
 
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The last thing you need with a failure is to add a distraction.

You don't need an artificial horizon when you can see the real one. Fly the airplane and don't play with toys.

That includes in IMC. You're trained to fly partial panel, right? Then fly it. Your workload will go WAY up without fiddling with your iPad.

Note that some vacuum pump failures can lead to additional problems due to broken pieces or oil leaks.
 
my one and only time happened in VMC, also. Didn't even realize it except my low vacuum light was lit. I do have an electric backup vacuum and stratus AHRS as options, but I agree about being glad I wasn't in IMC.
 
MAKG1 said:
The last thing you need with a failure is to add a distraction.

You don't need an artificial horizon when you can see the real one. Fly the airplane and don't play with toys.

That includes in IMC. You're trained to fly partial panel, right? Then fly it. Your workload will go WAY up without fiddling with your iPad.

Note that some vacuum pump failures can lead to additional problems due to broken pieces or oil leaks.
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I ran through the list of other things that this could cause once I covered the DG. Oil pressure was good (and stayed that way) & temperatures were good. I didn't really need to worry about flying the plane with partial panel...it was severe VMC. I just kept my head out of the plane as before.

There would have been plenty of time left to set up the iPad without falling out of the sky.
 
When all else fails, fly what you got to get on the ground. My CFII's sick sense of humor. He left me the iPad and my Garmin 496 because they were both battery. That day also had 45+ knot headwinds.

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Post it notes work well as covers and they take up little space in the bag.
 
New outright (no core charge), local is $384.
Overhauled with core turn in, local is $263.
No tax on aviation stuff in Kansas.

$1,600 for an Airwolf wet vacuum pump. Machined aluminum pump. 2,000 hour warranty.
It says it is a PMAd as a direct replacement for 200 series Rapco pumps...

Thoughts?
 
Kiddo's Driver said:
New outright (no core charge), local is $384.
Overhauled with core turn in, local is $263.
No tax on aviation stuff in Kansas.

$1,600 for an Airwolf wet vacuum pump. Machined aluminum pump. 2,000 hour warranty.
It says it is a PMAd as a direct replacement for 200 series Rapco pumps...

Thoughts?
Click to expand...

You'd also need the oil separator for the wet pump, and the installation. More money.

400 hours didn't wreck the pump, probably. Either the plastic drive coupling failed (they age and the recommendation is a six-year replacement interval) or oil or cleaning solvents got into the drive and seeped into the pump. that gums things up and causes failures.

I would recommend a brand-new Rapco or Tempest pump. They have inspection ports so you can check the vane wear and replace the pump before it fails. The Rapco has the inspection port on the side and comes with a little special dipstick for measuring vane wear. Tempest has a port on the back for a visual check. If your pump access is open enough I'd recommend the Tempest, since theirs has an closed drive to keep oil and solvents out and uses a little gasket to select the appropriate port for drainage of any oil that gets out of your engine's pump drive seal. Your's isn't leaking, is it?

Rapco's inspection hole has a tiny screw to close it, and it strips easily. But it works where there's too little access to the back of the pump for a Tempest.

http://www.tempestplus.com/pricesliterature.aspx
 
I believe there is plenty of room to go with the Tempest! On the downside, it looks like my Socata Tampico is not on the approved list.
We checked the vanes last year & they were good. Lots of material left. I'll have to look to see where the pump intake is at to make sure it is not sucking in oil.
I have not removed the cowl yet. I parked it Sunday and walked away. I've been busy & I think my mechanic is out of the country again anyway.
I'll go new just so I can crack the old one open & take a look. ;)
 

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If you can afford it, wet pumps are the best there is. With a dry pump, you're guessing when it will fail, not if. After 300 hours the pucker factor goes way up when IFR. A wet pump is more of a lifetime investment. Mine has over 3000 hours and still works like new.
 
Kiddo's Driver said:
I'll have to look to see where the pump intake is at to make sure it is not sucking in oil.
Click to expand...
The pump's intake is the vacuum line to the firewall. It won't suck oil through that. An oil-contaminated pump gets the oil from the engine's drive adapter when the seal there starts leaking and spitting oil. It can get into the drive end of the pump there, or if the pump's mounting flange is the old open type, it can get in there from other leaks on the engine, or cleaning solvents get in there.
 
Dan Thomas said:
The pump's intake is the vacuum line to the firewall. It won't suck oil through that. An oil-contaminated pump gets the oil from the engine's drive adapter when the seal there starts leaking and spitting oil. It can get into the drive end of the pump there, or if the pump's mounting flange is the old open type, it can get in there from other leaks on the engine, or cleaning solvents get in there.
Click to expand...
That makes more sense. It is a new enough design to include the vane inspection ports, but I don't know about the pump to case seal or if it is the "old open type".

tyndall said:
If you can afford it, wet pumps are the best there is. With a dry pump, you're guessing when it will fail, not if. After 300 hours the pucker factor goes way up when IFR. A wet pump is more of a lifetime investment. Mine has over 3000 hours and still works like new.
Click to expand...
The wet type sounds like something that you add at overhaul or on a machine you intent to fly the heck out of. A Tampico is not a hard IFR bird. I'll hold off on wet until the next plane.
 
My only vacuum pump failure was a long time ago and it was also clear weather, I was in the middle of my instrument training, so I put the hood on and flew for an hour or so until we got home. I had a pilot buddy in the right seat. My 182 was in for annual last week and my mechanic called and started talking about the vacuum pump and I cut him off mid-sentence, just replace it! It is the same one that was on it when I bought it, I think it was put on at overhaul, so it has 500+ hours on it, just replace it! My son wants to work on his IR and I don't want to have it crap out on him if I can help it. :)
 
I knew I was in good shape based on hours & inspection, but failed to take into account age effect on the (probably) plastic shaft and oil seals. I would bet that one or both failed. We will see.
 
I had a vacuum pump failure in the Turbo Arrow, which has a wet pump which is directly mechanically driven from a shaft going in to the engine case.

It was in VMC so that part of it wasn't a big deal, but I didn't know what the mode of failure was. For all I knew, there could be a broken or missing shaft, and oil spewing out of the engine case, so I decided not to chance it and returned to the airport.
 
Sac Arrow said:
I had a vacuum pump failure in the Turbo Arrow, which has a wet pump which is directly mechanically driven from a shaft going in to the engine case.

It was in VMC so that part of it wasn't a big deal, but I didn't know what the mode of failure was. For all I knew, there could be a broken or missing shaft, and oil spewing out of the engine case, so I decided not to chance it and returned to the airport.
Click to expand...

The fact that I had a dry pump played into me continuing on for 30 more minutes. That is a down side to a wet pump I had not considered...
 
My (dry) pump is almost 600 hours old and now I'm starting to worry!
 
mkosmo said:
My (dry) pump is almost 600 hours old and now I'm starting to worry!
Click to expand...
How many years?
Mine had the inspection port. We had checked it at annual in 2015 and the carbon impeller was in very good shape. 400 hours on the pump. What got me was AGE. 12+ years made the plastic brittle and it simply snapped.
Carbon impeller -> hours in use
Plastic parts like the shaft -> age (Plus probably where the plane is stored. Baking in the Texas sun will probably not be good for the plastic parts.)
 
Can someone clarify wet vs. dry vac pumps for me? In my mind a "dry" pump is an electrically driven one, or one operated by any means other than plugging into the accessory case. The wet pumps are the traditional pumps driven off the accessory case. Is this right?
 
Arbiter419 said:
Can someone clarify wet vs. dry vac pumps for me? In my mind a "dry" pump is an electrically driven one, or one operated by any means other than plugging into the accessory case. The wet pumps are the traditional pumps driven off the accessory case. Is this right?
Click to expand...

No, not close. But you never know until you know, and how can you know without asking?

"Wet" pumps" are called wet because they are oil-lubricated, generally all-metal designs. Plumbed with oil under pressure, and they last a Very Long Time, but you must also (generally) use an air-oil separator to remove oil from the discharge, or you will vent a great deal of it overboard. More costly, more complex, very reliable.

"Dry" pumps are mechanically simple, have carbon vanes which float in channels carved into a carbon block, all spun through an elastomeric (plastic) coupling. No oil feed required. But, the vanes will wear as the pump is used, by design, they rely upon the graphite from the wear for lubrication. Generally good for a bout 500 hours or so before the vanes get short enough that they break and the pump is dead (can also happen when one rotates the engine backwards, blades bind and break). Dry cost less.
 
Kiddo's Driver said:
How many years?
Mine had the inspection port. We had checked it at annual in 2015 and the carbon impeller was in very good shape. 400 hours on the pump. What got me was AGE. 12+ years made the plastic brittle and it simply snapped.
Carbon impeller -> hours in use
Plastic parts like the shaft -> age (Plus probably where the plane is stored. Baking in the Texas sun will probably not be good for the plastic parts.)
Click to expand...
Coming on 10. That's the other part that has me concerned. The pump lived half her life on the Louisiana coast which is just as bad.
 
GMascelli said:
When all else fails, fly what you got to get on the ground. My CFII's sick sense of humor. He left me the iPad and my Garmin 496 because they were both battery. That day also had 45+ knot headwinds.

View attachment 46346
Click to expand...

This was how I had to fly an approach before being signed off for my IFR ride lol

324241_2198055992343_1171783743_o.jpg
 
I practiced approachs with the 496 , worked great. I have also flown with the synthetic vision on the I Pad,why would you buy it ,if your not going to use it?
 
SCCutler said:
No, not close. But you never know until you know, and how can you know without asking?

"Wet" pumps" are called wet because they are oil-lubricated, generally all-metal designs. Plumbed with oil under pressure, and they last a Very Long Time, but you must also (generally) use an air-oil separator to remove oil from the discharge, or you will vent a great deal of it overboard. More costly, more complex, very reliable.

"Dry" pumps are mechanically simple, have carbon vanes which float in channels carved into a carbon block, all spun through an elastomeric (plastic) coupling. No oil feed required. But, the vanes will wear as the pump is used, by design, they rely upon the graphite from the wear for lubrication. Generally good for a bout 500 hours or so before the vanes get short enough that they break and the pump is dead (can also happen when one rotates the engine backwards, blades bind and break). Dry cost less.
Click to expand...

Makes sense. Thanks, Spike! Have a great day!
 
There is also a dry pump that is more reliable than the typical carbon vane and carbon block such as the pump the op had.
It is a sigma tek. It has a metal rotating block and much stronger less brittle carbon fiber vanes. I replaced this one with 850 hours on it still running strong. New the vanes will fill the width of the groove.
 

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Kiddo's Driver said:
I lost my vacuum pump yesterday in severe VMC. The spinning DG was distracting, so I hung a wash cloth over it. Other than that it was a non event. I would hate to have that happen when in IMC.
Click to expand...

It's not fun, but partial panel training makes it doable. I did it with the family onboard in IMC and I'm no Chuck Yeager. In my case it was a spinning HSI, but same annoyance.
 
FORANE said:
There is also a dry pump that is more reliable than the typical carbon vane and carbon block such as the pump the op had.
It is a sigma tek. It has a metal rotating block and much stronger less brittle carbon fiber vanes. I replaced this one with 850 hours on it still running strong. New the vanes will fill the width of the groove.
Click to expand...
Now you tell me! I just replaced mine with the standard dry pump.
 
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