Gascolator won’t seal (old glass bowl style)

[phxcobraz]

Have a 63 C. Noticed the gascolator bowl dripping some after flights a while back, tightened and it was fine, but started again. 
Dissasbled, seals look great, cleaned off some corrosion, with a scotchbright and reassembled. Still leaks and worse now. It’s as tight as I can get it. 
I made some new seals with cork and it will seal up better now but if I push in it side to side it will still leak. 
Any advice? I ordered a Steve’s Gascolator at recommendation of my IA but would like to get this working if possible since he can’t do that install for a bit. 

 

[N201MKTurbo]

I would clean it a lot more. I would use some 800 sand paper and try to get all the corrosion off the gasket surfaces. It wouldn’t hurt to clean the outside and paint it. Just mask the glass, paint it, then take it apart, clean the glass and put it back together. You can use the sand paper on the ends of the glass. Lacquer thinner will take the fuel stains off. 

[phxcobraz]

22 minutes ago, N201MKTurbo said:

I would clean it a lot more. I would use some 800 sand paper and try to get all the corrosion off the gasket surfaces. It wouldn’t hurt to clean the outside and paint it. Just mask the glass, paint it, then take it apart, clean the glass and put it back together. You can use the sand paper on the ends of the glass. Lacquer thinner will take the fuel stains off. 

Makes sense, where you can see the build up is exactly where it’s leaking. The pics are before I did any sanding, it’s much better now. I will hit it again and maybe that’s all it needs. I’m guessing at some point water sat in it long enough, though I’ve never found water in 2yrs. 

[Guest]

6 minutes ago, phxcobraz said:

Makes sense, where you can see the build up is exactly where it’s leaking. The pics are before I did any sanding, it’s much better now. I will hit it again and maybe that’s all it needs. I’m guessing at some point water sat in it long enough, though I’ve never found water in 2yrs. 

A new Steve’s Aircraft machined aluminum gascolator is less than $500 and STC’d for your Mooney.

[phxcobraz]

24 minutes ago, M20Doc said:

A new Steve’s Aircraft machined aluminum gascolator is less than $500 and STC’d for your Mooney.

Yep I ordered one for $300 yesterday at suggestion of my IA. It looks so pretty it’s sad it won’t ever be seen.
But my IA is out on his honeymoon and I would like to fly before he can get back and handle swapping and the 337. 

[N201MKTurbo]

I always try to rehabilitate old parts, but some time you have to throw in the towel.

[Utah20Gflyer]

6 hours ago, N201MKTurbo said:

I would clean it a lot more. I would use some 800 sand paper and try to get all the corrosion off the gasket surfaces. It wouldn’t hurt to clean the outside and paint it. Just mask the glass, paint it, then take it apart, clean the glass and put it back together. You can use the sand paper on the ends of the glass. Lacquer thinner will take the fuel stains off. 

I would agree, another possibly useful technique would be to use lapping compound to resurface the mating surfaces of the parts.   Whatever the technique those surfaces need to be really clean and smooth to get a good seal.

[skykrawler]

With things like that, patience is a virtue.   You got sound advice to replace that thing.  The safety wire is on that 'harp' for a reason.

And I would make a couple of close patterns for that check-flight once it's back together.  Face the reality that the fuel system is a critical system, everything should be top notch.

[Guest]

If you were to remove it from the plane and examine it carefully, you’ll likely find that the top casting is warped from years of over tightening against old stiff seals.  This happens to the same part in Piper Cherokees.

[A64Pilot]

For a one time shot, apply fuel tank sealer to the sealing surfaces, both sides and assemble wet and put only enough pressure to hold it together, let it cure overnight then next day snug it up.

If this doesn’t seal it up, it’s likely not much will, then of course when the new one comes in, replace it.

Some aren’t but personally I’m a fan of glass gascolator that you can see the bowl without disassembling the aircraft.

If you don’t have any B2 fuel tank sealer order it and keep it in the fridge or freezer, it will keep that way for years and is very useful stuff, think like silicone, but really works and is both fuel and oil proof. Order a small can as it’s easy to mix small batches that way

[phxcobraz]

So good news today. After further sanding on the top of the cup and using a new cork gasket I made up it no longer leaks. I did find positioning while tightening the bail is key, if you just tighten it will tend to slide to one side and not compress evenly against the gasket. Safety wired it up and did a long taxi around and a couple run up’s, no leaks. Will check and do a few more and then some pattern work but happy with the results until we can replace with the Steve’s unit. 

[Fly Boomer]

19 hours ago, A64Pilot said:

Order a small can as it’s easy to mix small batches that way

Do you find that the mixing ratio is critical when using it out of a can?  Or is it somewhat forgiving?  As I type this, I'm thinking the mixing ratio is probably less than perfect with the cartridges, even though the correct quantities are in the tube, the mechanism for mixing is a little hit and miss.

[A64Pilot]

It’s very easy to mix by color, you mix for that dark grey. Only a tiny bit of black is required, less than you would think.

Army we only had the cans and even had some red / white every now and again instead of the normal black / white. Never had an issue unless it was out of date, we used it on everything on Bell Helicopters, every sub gearbox that bolted to the transmission, mast boots etc.

Only way you get the mix right with the tubes is to mix the whole tube or go by color, if you mix the whole tube, immediately freeze it, it will keep for a month or two if frozen. Some factories even buy it pre-mixed and frozen.

Factory I worked at we had air / electric machines that mixed the tubes. The mixers were several thousand dollars a piece, but if your patient you can do just as well by hand, some will even cut the mushroom piece off of the small tube and use a drill, but I don’t think that’s necessary and if you get silly with it you can add heat and it will cook off much quicker than 2 hours if B-2.

I like the cans as I mix small batches once in a blue moon.

[Butch]

If I remember correctly the top gasket diameter and width is slightly larger than the bottom.  If you still have problems mic out the top "lip" diameter and add the glass thickness plus some to determine the diameter and width of the gasket you need. 

Sometimes with 2 of the smaller gaskets (bottom), you could get it to seal. If you use the old bottom gaskets as a pattern you haven't solved the problem.

I can't remember the numbers, but it may have been a 2 1/4 top and 2 3/16 bottom.

[phxcobraz]

Mechanic and I got the new Steve’s gascolator installed. Much better design and fairly straight forward. About 2hrs work. 
 

[carusoam]

Nice work phxc!

If Steve’s solution doesn’t meet expectations….

M20Cs went away from this type of separator in 1965…

But, that is a complete rework of the fuel system…. 
 

Pre-flown parts are always available…

Best regards,

-a-

[Guest]

It looks like you’ve missed installing one of the mounting bolts, that goes through the original Mooney bracket.

[carusoam]

@phxcobraz see note above from Doc…

Best regards,

-a-

[phxcobraz]

On 11/5/2022 at 4:03 PM, M20Doc said:

It looks like you’ve missed installing one of the mounting bolts, that goes through the original Mooney bracket.

Ahh yes good catch. I took this while he was finishing up still. I had smaller hands and helped drill and put the cotter pin in.