Gascolators

Tom-D

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Tom-D
Started new thread because Yes it was major thread creep on the forum.

This is why I inspect the gascolator on every annual.
The pictures below are of a Gascolator I removed from a 150, I don't believe it had ever been off prior to this. You'll see the corrosion that occurs in these fuel strainers, you can see the brass 100 mesh screen, which is supposed to separate the water from the fuel, From the looks of it it has never been cleaned or serviced. The "O" ring is hard and brittle, and the whole assembly is dirty, corroded.
Those that believe these do not require inspecting just because they have no AD, are the inspectors you do not want doing your annual.
 

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From the 100 hr / annual inspection checklist in my 182's service manual:

2-15

Fuel System
1. Fuel strainer for internal cleanliness, security, leaks, and safetying; drain valve and control for proper rigging, operation, leaks, and security.
 
The "O" ring is hard and brittle, and the whole assembly is dirty, corroded.

That O-ring came off in one piece? Can't be more than 20 or 30 years old;) I sometimes see them crumble into little bits when they come off.

I think a lot of airplanes get maintained like cars. Fix it when it quits. That's usually when the fuel filter on a car gets replaced.
 
From the 100 hr / annual inspection checklist in my 182's service manual:

2-15

Fuel System
1. Fuel strainer for internal cleanliness, security, leaks, and safetying; drain valve and control for proper rigging, operation, leaks, and security.
It's pretty evident that some inspectors don't use that as the required list as mentioned in FAR 43-D.
 
I replaced the gasket on mine at the last condition inspection. When I pulled the gascolator to clean/check the screen, I found that the gasket had turned brittle - it actually cracked when I flexed it. So I flexed it again. And a new crack formed. Another $3.50 down the tubes. ;-)
 
I replaced the gasket on mine at the last condition inspection. When I pulled the gascolator to clean/check the screen, I found that the gasket had turned brittle - it actually cracked when I flexed it. So I flexed it again. And a new crack formed. Another $3.50 down the tubes. ;-)

That's a really old gasket. The screen gasket usually lasts quite a while. It's the two O-rings that should be replaced periodically: The MS29513-111 at the bottom, and the MS29513-138 at the top, in the groove where the top of the bowl goes. Then there's the MS29513-010 inside the top body, to seal the plunger shaft. That one is plenty of fun to replace, especially in a crowded compartment.

The above applies to the typical legacy Cessna strainer. There are numerous other types. When strainers get too old and worn out, repairs can be expensive. Steve's Aircraft has STC'd gascolators that are easier to work with: https://www.stevesaircraft.com/gascolator.php
 
I can replace a lot of Orings for what they want for one of them.

O-rings aren't the issue. Rotted-out bowls, failed plunger tips, standpipes chewed up by mechanics using vise grips, or their valve seats corroded and leaking, screens falling apart: those are the issues. Even the aftermarket parts aren't cheap. The Steve's gascolator uses a single reusable O-ring (metric, mind you, so order spares), a simple screen disc, and you install your own curtis drain valve in the bottom. Cheap to maintain and real easy to open and clean.
 
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Yep, especially if you find the pilot has been illegally running some amount of unknown autogas in the thing. We've found some Navion crashes that we're pretty sure were caused by ethanol. There are no STCs for autofuel in the NAVION and there are no STCs that permit any amount of ethanol in the autofuel they allow.
 
O-rings aren't the issue.
They are the only issue when you do the inspection and find a good unit.
If you don't find a good unit, 99% of owners will call salvage and get another.
I don't believe I would advise any owner to buy a $300 replacement when a used good unit is $100 or less.
 
That's a really old gasket. The screen gasket usually lasts quite a while. It's the two O-rings that should be replaced periodically:

My gascolator has one gasket and an o-ring in the drain. The assembly is inspected every year and parts are replaced as necessary. It is a 10 minute job, including the leak check afterwards.
 
This is of extreme importance, but a chunk of broken metal inside the engine is no big deal? Ok.
 
They are both serious.

You have to wade through the BS and diatribes to find any value. Welcome to the internet - take everything with a large grain of salt and do your own homework to make your own decision.
 
Started new thread because Yes it was major thread creep on the forum.

This is why I inspect the gascolator on every annual.
The pictures below are of a Gascolator I removed from a 150, I don't believe it had ever been off prior to this. You'll see the corrosion that occurs in these fuel strainers, you can see the brass 100 mesh screen, which is supposed to separate the water from the fuel, From the looks of it it has never been cleaned or serviced. The "O" ring is hard and brittle, and the whole assembly is dirty, corroded.
Those that believe these do not require inspecting just because they have no AD, are the inspectors you do not want doing your annual.

Welcome to cheap and fast annuals. Complacency at its finest!
 
Started new thread because Yes it was major thread creep on the forum.

This is why I inspect the gascolator on every annual.
The pictures below are of a Gascolator I removed from a 150, I don't believe it had ever been off prior to this.

From the looks of the teeth marks in the first pic, looks like someone long ago had some water pump pliers on the bowl, for some reason, I see those every now and then, but like the above said, some pilots are looking for cheap inspections
 
Of all the years I’ve been wrenching I check mine every 25 hours, yep I know overkill. Usually not an issue it’s clean,but I have cleaned corrosion, If you catch it early and keep it clean it’s not an issue. Not mentioned,I call it the last chance filter on the Carb, I am talking about small Continentals. If I don’t find FOD in the strainer, if I do,I also pull it, usually find hair,little black pieces, bought a tagged carb,fresh overhaul, no filter in it at all. Looks like a sewing thimble. I worked at a flight school for 8 years, every 100 hrs we pulled the gascolator, and the last chance filter. We had 16 Cessna 150s averaged 8 100hr insp every month. Oh the good old days.
 
Very common to see gascolator in the above condition when a plane has been sitting. It's the lowest point in the fuel system, as evidenced by the corrosion from water.

I agree with the above post, this piece is frequently overlooked on annuals. So much for the many log books that say "annual inspection done in accordance with Cessna Maintenance Manual".

It's a shame since like others have said, the annual required maintenance parts for the gascolator are inexpensive.
 
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Recently read a story about a guy who bought a super cub from down in Oregon. He flew it back to Fairbanks and had to make and off airport landing for an “engine problem”.

Turns out the previous owner had apparently been filtering his gas through a chamois. But, must’ve been placing the chamois rough side down over the aircraft filler neck. The gascolator was full of fibers from the chamois. New owner said it looked like the gascolator had never been inspect.
 
Oh, I thought perhaps you thought you were in this thread about the metal part in the engine; if not ignore.

It was the end of an oil ring that had broken off and came through one of the holes in the oil ring groove of the piston. It must have just happened because the owner said it did use a little extra oil on their last leg.

I would have posted the results on the other thread but some people could not get along and got it locked. That stopped any additional productive inputs that anyone might have had.
 
That is nice to hear that it was confirmed that it is minor in nature (relatively).
 
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