leaking gascolator

FORANE

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FORANE
I found fuel dripping from my Lancairs gascolator today. Are those rebuildable with o rings?
 
Yes they are. They should be disassembled, cleaned, inspected and reassembled with new seals/o-rings at annuals. Like I said they should but that's not always the case.
 
A homebuilt could have any one of a variety of gascolators in it. All of them use seals of some sort, and old styles use rubber or cork washers. The old ones had cast zinc bodies and a glass barrel with a cast or wire bail to clamp everything together. They warp and crack. The glass chips and shatters. They leak, even with new seals sometimes.

I regularly encounter gascolators, mostly on Cessnas, that haven't been opened in many years. This is insane. There's a fine brass screen in there to catch debris that might cause fuel flow trouble, and it should be checked and cleaned every year. We find fuzz of indeterminate origin in some of them. We find the drain plungers with rotted-off tips. Leaking plunger seals. Internally corroded sediment bowls, ready to perforate right through.

See this for new, sensible gascolators: http://www.stevesaircraft.com/gascolator.php
 
20180106_131841.jpg 20180106_131851.jpg Got it removed.
Looks like a Garwin G199-90B
Anyone know where to get rebuild parts for these?
 
Back in the day z lot of automotive technology was adopted by the airframe manufacturer's. Alternators, being better than generators suddenly became the word of the day.

Every aircraft I have worked on had an original alternator or generator that was not capable of meeting demand.
 
Got it removed.
Looks like a Garwin G199-90B
Anyone know where to get rebuild parts for these?

That is a very old gascolator. You find them on 1950s Cessnas. Hard to find any hard parts, but the rubber seals might still be available. Check with your Cessna dealer. It might be cheaper to install a new one.
 
Had one on my 56 182. I just made my own cork gaskets.
 
That is a very old gascolator. You find them on 1950s Cessnas. Hard to find any hard parts, but the rubber seals might still be available. Check with your Cessna dealer. It might be cheaper to install a new one.
That makes sense as my 320 is from the late 40's I think. Thanks for the info.
 
In stead of cork, it would be better to make new gaskets from sheet silicon rubber (the hi-temp red stuff) as an owner produced part.
 
In stead of cork, it would be better to make new gaskets from sheet silicon rubber (the hi-temp red stuff) as an owner produced part.

Silicone is a very poor choice for fuel. It can swell mightily, crumble and cause lots of trouble. https://www.marcorubber.com/o-ring-chemical-compatibility-chart-7.htm

The old gascolators used cork, which was later replaced by a rubber seal, probably Buna-N.

The OP should check this: https://www.aircraftspruce.ca/menus/ep/gaskets_gascolator.html

If you check those gaskets, go to the Q&A tab; they give you the dimensions. One of them is likely to fit that ancient gascolator. You'll need two of them.
 
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I had in mind the red/orange stuff that among other applications, is used by RealGaskets for rocker box covers etc.

That MarcoRubber table is interesting. Best of course is probably the ACS gascolator seals by size. Anything but cork.

Later - Something cut from Buna-n or a flourosilicone sheet would be appropriate for gasoline according to McMaster-Carr. You are correct that the traditional red silicone used for baffling etc is not gasoline resistant (didn't know that). My bad. THX
 
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All the gascolators I’ve had on my planes used a 2” or 2-1/8” rubber washer type gasket. I’ve always bought from Aircraft Spruce, Univair, or Wag-Aero.


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I’ll vouch for Steve’s Aircraft gascolators, put one on my Champ, it’s a nice piece of kit.
 
Yep, if a ‘Steve’s’ is available for your plane, go that route. I detest a leaky gascolator, it’s a fire hazard.
 
My leak was coming from debris in the o - ring of the quick drain. I have cleaned it and plan to replace the drain.
05-01869.jpg
 
In case you haven't found the gaskets, here is some further detail. As Dan mentioned you can get these gaskets from Aircraft Spruce, P/N 33-00199-6 (link: https://www.aircraftspruce.com/catalog/eppages/cessnagasket33-00199-6.php ). There are two gaskets one on the top and one on the bottom of the bowl. Cessna used the same gascolater, thus parts are still available. I just replaced the old cork gaskets on my Garwin gascolator and the rubber gaskets are far superior. Make sure the gaskets are warm when you perform the installation - you will get a better seat that way. Even if your leak was from the drain valve I would recommend replacing the main gaskets - very easy to do.
 
I have installed the quick drain and flown the plane. Thanks for the link. I may just replace the gaskets next time I have the cowling off.
 
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