I installed the new style fuel valve in 2004 and everything was good. Now I've notice the last two years (winters) that when it gets down to about -15 or more below, the valve starts to leak where the handle stub exits the valve. I triple checked all connections and it only leaks when cold.
Anyone else have this going on? Is there an O ring that's shrinking?
The paper work says "do not disassemble valve. no field serviceable parts inside."
jk
There are 4 stainless steel balls and springs in there along withe some o'rings. You pop the snap ring out and slip a piece of tubing over the stem before you pull it out otherwise you get to go looking for those balls like I did before I read Super Cub MD's article in the Cub Clues. I'll see if I can find it and post it here.
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
The O-Ring listed is M83248 /1-011. This is the 4 way valve.
Piper J-5A C-90 N40877
J-5 Project Pictures
jk wrote
I'm curious what fuel you use.Is there an O ring that's shrinking?
Just hold your hand around the "shunt" as you push it out in order to catch the balls. I've pulled these apart a few times and no problem with catching the balls.
Take care.
Crash
"The fear of God is the beginning of wisdom". Psalm 111:10
I usually use a baggie around it, to catch them coming apart.... then a piece of white plastic pipe coupler to hold them in during assembly....
not sure on new orings,
but know the valve dries out if dry after it has been used, like during rebuild, you should leave it soaking in a sealed can of fuel or such......... they so far have all quit leaking after a day or so wet again.....
Had mine apart more times than I care to remember. Replaced the "O" ring on the face of the cylinder several times as it was being cut by the poor quality machine work on the valve. Ended up replacing the valve completely, no problem since. Mine was not however a Univair valve. It was from those other guys........a bit further west. !!
A steel shotgun shell BB will replace a lost ball in a pinch! Every time we have had a cub that sat for awhile {as in rebuild} the valve has needed new O-rings to stop the leak. I tape a wrap a white towel around the stem as I pull it out and let it catch the 4 springs and balls now. Everyday O=rings from a NAPA kit have worked perfectly on all the ones we have fixed in the last couple years.
Dave
Thanks.
I use Avgas. Nice blue stain
David; got mine from Dan's.
Mike; no dry valve here. its fine until it gets chilly
Steve, Greg; thanks for the heads up on catching balls.
jk
Originally Posted by david jaranson
.....as it was being cut by the poor quality machine work on the valve.........Mine was not however a Univair valve. It was from those other guys........a bit further west. !!
Ummmmm does that brand start with a D? I have a new dakota one going in this project, should i be checking it out before i install it? or was it a learning curve of there's or a different brand?? I like the idea of "both" position STC'ed in this 12 with it....
nope....mine was from CC
oh good had me worried....nope....mine was from CC
Univair and CC are both the same valve. CC is a 4 way, Univair is a 3 way.nope....mine was from CC
Piper J-5A C-90 N40877
J-5 Project Pictures
Made by Allen Company. Glad to know I am not the lone ranger. Tanks dry for a month or two for some repairs and we had a leaker.
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
so how do the dakota ones do like I have??, any track record yet?
I believe it is the same valve but it has the limiting screw on the back to meet the new regulations so you can't go to "off" from any position. That is why CC has the two bolts and spacers on the fuel selector panel.
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
I've noticed that my fuel selector has got real stiff (to turn) since sitting for a year. Makes sense that it has dried out, but I'm wondering if it will smooth out (be serviceable) again when it gets a gas-soaking.
I press-tested my fuel lines w/air & soapy water, but now want to pour some gas in, & test the primer for pressure & leaks. Last check before putting in the int. panels.
Idea: Good_ Bad_ Ugly_
Nimpo Lake Logan... boonie SuperCubber
200mi (300km) from nearest stoplight... just right! - "Que hesitatus fornicatus est"
Is it an Allen valve or an original Piper valve. If a Piper valve (Imperial I believe) take it apart and inspect the cone, install a new o'ring and lubricate with Ez Turn. http://www.aircraftspruce.com/catalo...ezturnlube.php It is fuel proof and non-hardening. I use it on pipe threads in the fuel system as well.
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
Stock valve is the best!! lube every year No problems change detent washer as needed those new valve leak in the cold also dry out with no fuel.
Steve
Do you have to drain all your fuel yearly to do this? The only problem I have had with the Allen valve is the one that sat for two months empty that leaked. The age of the valve is unknown.
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
Its amazing how guys with a $50K plus flying machine won't spend $250.00 on a fuel valve that does not leak.
Piper J-5A C-90 N40877
J-5 Project Pictures
The part that gets me though is why you should have to buy a $250 valve to get one that doesn't leak. Mine, in my Experimental, are $2.49 ball valves from a Hardware store. Been in there for 15 years now...and have NEVER leaked.
do you drain them? I use a soft float ball, and pray lots that I don't drop anything....
Do you have to drain all your fuel yearly to do this?
sure don't miss cleaning and lubing fuel old style valves....
Mike, I take it you pull the stem and stick the ball in the valve body?
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
No you don't have to drain the fuel, spare fuel cone is used to keep the fuel from leaking while i lube and check as far as spending $250.00 for one that don't leak find me one that works at -40 all the time and will take it!!!!!!!!!!!!
Steve
24A-
The allen valve is "supposed" to be designed to -65....
Tim
Piper J-5A C-90 N40877
J-5 Project Pictures
yup and have someone then hold the ball while you clean I seen guys do it alone and "screw" the ball in some and leave it, kinda scary...... rags for if you make a big mess...... but usually goes quick.....
My mechanic replaced the O rings in a CC valve. No external leaks, but now the valve doesn't shut off the fuel completely - fuel will drip (not stream) through the gascolator valve. Any ideas?
Steve
Probably a bad o'ring seal. I'd take it apart and replace the o'rings again and it should fix it. Might make sure all the mating surfaces are good also. I have put new o'rings in different things over the years and still had a leak when everything appeared good. Disassembled and replaced them again and all was good. It is aggravating but it happens.
Steve Pierce
"When everything seems to be going against you, remember that the airplane takes off against the wind, not with it."
Henry Ford
What size ball should I use to plug the valve while replacing the rings? When we did it before, the valve was off the plane during a rebuild.
Steve
sorry you gotta drain it.... ball trick only for old style valves.....
boy would you be mad at me had you tried that!!
[update] Replacing the o-ring fixed it. I had to drain the fuel, but didn't have to remove the valve.
But, what's cool about this is that I can get a nearly instantaneous answer from people who have actually done the work before. Saves lots of heartburn.
Thanks for the help.
Steve
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