Fuel Selector Valve

Skymaster337B · #1 11-15-06, 09:30 PM

Has anyone ever rebuilt a fuel selector valve? Specifically, do the checkballs usually wear out, and are those checkballs easy (and cheap) to get from Cessna?

Any other hints would be appreciated.

Guy Paris · #2 11-17-06, 11:56 AM

Check with Don Nieser.. guy paris

Don Nieser
405-722-4079
405-503-4686 cell
nieser.02.337parts@juno.com

Richard · #3 12-09-06, 03:31 PM

They are not hard to rebuild, but kind of a pain to remove. What I found most troubling on the unit is the cork gasket. They tend to shrink over time and can start to leak.

If you are experiencing "sticky" valve switching, most times the check balls can be cleaned and re-lubed with no appreciable wear on the surface. Cable friction is also a culprit of those symptoms.

We pulled the valves and found the majority of the resistance due to dirty solid core wires going to the valve. The cables were removed, cleaned, and re-installed. Now, they are like butter.

Skymaster337B · #4 12-09-06, 09:37 PM

The problem I'm having is the valve sweats. I tried to tighten the screws on top but it's almost impossible because my hands are too big to get around the fuel lines. It seems like there should be an access panel on top of the wing, but of course there's not, and it's a structual panel.

I found a small screwdriver at Sears, it's only a 1/2" tall, but the handle is a very round wheel that I can use with just my fingers. I'll try that.

But if I have to remove the valve from the wing (to replace the cork seal) do you have any tips/tricks to pull it out?

KyleTownsend · #5 12-19-06, 10:46 AM

I have a T337G model, and we recently noticed that fuel would still drain from the front engine fuel sump with the front engine fuel valve closed. Of course, we immediately suspected the valve. However, tapping on the check-valve for the fuel return line from the front engine back to the tank quickly revealed that this was the actual culprit. Might be something you want to check.

Of course, the fuel valve setup is somewhat different on the B models vs. my T337G, so these comments might not apply to your situation.

Skymaster337B · #6 12-19-06, 06:26 PM

That's some good info about the fuel strainer. I will certainly put that in my shop notes. However my actual fuel valve is what's acting up. So I might have to pull it out and rebuild it; however, there is no easy way to do that because of the tight space in the wing.

Does anyone know of a short cut to remove the fuel valve from the wing?

#7 01-31-11, 11:23 AM

Skymaster337B, Did you ever sort out your fuel selector problem?

Skymaster337B · #8 01-31-11, 04:11 PM

No, do you have a 411 on a gasket part number?

hharney · #9 01-31-11, 05:58 PM

Item 10, is this the gasket (packing) you are looking for?
M83248/2-906
http://www.cessnaparts.com/search.cfm

Skymaster337B · #10 02-01-11, 05:33 PM

Thanks for asking. But item #10 is an o-ring, around a b-nut. The gasket I'm talking about is a cork type gasket that seals the entire wing-mounted fuel selector valve body. Unfortunately the parts manual only lists it as a complete assembly. I new assembly was $15K the last time I checked...not going to happen. I will make my own gasket if I have to, but always like getting new parts if they are available...plus the maintenance down time is quicker.

Kim Geyer · #11 02-01-11, 08:55 PM

Check McFarlen Aviation, they just started selling kit for cessna valves. Just put one in our 185 and it was @$90.00 Don't know if they have kits for 337's though. you can check their web sight
Kim

awilps · #12 01-04-12, 09:20 AM

Hi all! I'm new to this forum, and just wanted to share that we located the cork gaskets for our O-2's fuel selector valve at B & S Aviation in Wichita. $75 a piece. They should arrive today! Hopefully a better solution than the $12,000 Cessna wants for a new valve. I'm a bit unnerved by the numerous listings of parts for this valve listed as "non-procurable" and "discontinued". Coupled with several overhaul shops telling me they won't touch these units...is there a serious problem with opening these units up? I'm new to the airframe and want to give our MX team as much info as I can. Cheers!

hharney · #13 01-08-12, 11:34 PM

Performing a search on the topic is the best way to access all info on the site about the topic. Doing so did not bring up too much about these valves. I haven't heard of any red herrings that these items have. Good luck

Skymaster337B · #14 01-17-12, 09:23 PM

Awilps, what part number did you use for the gasket?

awilps · #15 01-18-12, 07:43 AM

The gasket we needed was B3-12-1. Lots of shops couldn't make any sense of the number, but it came up correctly in B & S's inventory. We have a '68 O-2A. We also found that the fuel line which runs all the way forward toward the leading edge of the wing from the the selector valve was very loose on both wings. Difficult to see and get to, but glad we did! So far no more leaks...I've been replacing almost every seal and o-ring since the ship came from a Florida home and is now working hard in New England cold wx. EVERYTHING has been leaking.