Imperial fuel selector maitence
- Thread starter Clifford
- Start date
Ursa Major
Registered User
Coeur d'Alene, Idaho
Several years ago I did the same thing. It had a "light" detent and I figured it would be okay. On the first takeoff after reinstalling it, I got to around 300' AGL before the engine quit. Fortunately I had enough flat ground in front of me to land without incident. I figured I had accidentally bumped it to the off position with my knee when doing the flap check on run up. So much for soft detents.
After getting it back to the hangar, I very carefully removed the fuel selector and threw it as far as I could. I then ordered a new one from Univair. It cost more than the old Imperial, but it has worked perfectly for several hundred hours and cost a whole lot less than rebuilding a wrecked airplane.
mike mcs repair
Registered User
chugiak AK
you put the cupped water in upside down would be my guess....
replace that valve with a modern one would be best solution....
replace that valve with a modern one would be best solution....
Supertwotwo
Registered User
I also need to overhaul my fuel valve and I would rather swap out the metal plug and position washer for this style Super Cub valve with the plastic plug, looks like a much better designed position washer, univair.com/content/PIP_SL0944.pdf
I cant find a source for this piper valve, has anyone installed one recently?
I cant find a source for this piper valve, has anyone installed one recently?
mike mcs repair
Registered User
chugiak AK
thats outdated technology.... get a new style one
Supertwotwo
Registered User
mike mcs repair
Registered User
chugiak AK
it's WAY outdated technology no one uses any more.....
DECADES ago, Univair came out with a much better valve... and Dakota cub makes a copy of it... get one....
mike mcs repair
Registered User
chugiak AK
the advantage to the Dakota one is in it's STC it gives you a legal BOTH position also
skywagon8a
MEMBER
SE Mass MA6
I don't agree with the "used on experimental aircraft only" comment. It is a standard part which Piper very likely purchased directly from Weatherhead. At the time that these airplanes were built the term FAA-PMA did not exist. I would have no qualms about using this valve, if as you say it is the same (very similar) as the original. I'm not suggesting that you not use a more modern valve, only that this particular valve doesn't need to be labeled "experimental". This is of course a judgement call.
Steve Pierce
BENEFACTOR
Graham, TX
Here is a lot of good information on maintaining the original fuel selector valve including how to fix that detent washer.
http://www.shortwingpipers.org/forum/showthread.php?7674-Fuel-Selector-Repair
http://www.shortwingpipers.org/forum/showthread.php?7674-Fuel-Selector-Repair
Supertwotwo
Registered User
I don't know if Piper fuel valve part 77413-02 that service letter 944 regards is a Weatherhead valve, but the design looks the same and it is the original equipment fuel valve in PA-18 Super Cubs from 1979 to 1981 and every PA-38 made.
According to service bulletin 354B it was offered as a replacement valve for the metal plug valve that came on my plane, that's why I would like to use it, a Piper fuel valve that doesn't require STC, and looks like a good valve. If they're around today and available I would like to use one and keep it as original as possible.
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wireweinie
FOUNDER
Palmer, AK
Amen.
Urea thanks for the heads-up. You would not possibly have a photo of the one from Univair ? I would like to see weather the Univair one will fit the same as the old imperial? My cub is scratch built so a little different than certified one. I have 1/2" fuel lines to feed the 205 hp lyc.
Steve Pierce
BENEFACTOR
Graham, TX
This is the valve Univair has PMA on.
http://m.aircraftspruce.com/catalog/appages/allenfsv.php
http://m.aircraftspruce.com/catalog/appages/allenfsv.php
Supertwotwo
Registered User
If you haven't removed the Imperial valve from your airplane, and you aren't working with a certified aircraft you have lots of options, you could try swapping out the guts (everything, the plug, position washer and valve cap, everything except the valve body) from the 30 dollar Weatherhead valve from Aircraft Spruce, maybe somebody here can tell you if they are interchangeable? If the guts aren't interchangeable than the Weatherhead valve should fit in place of your Imperial valve. The Weatherhead guts are pictured below, actually it's a picture of the Piper valve in sl944 but the Weatherhead is the same. The second picture is the Imperial valve from sb354b, I would try swapping the guts since you have that option being experimental.
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Ursa Major
Registered User
Coeur d'Alene, Idaho
Before I ordered a new PMA valve from Univair ( same one Steve shows) I tried 3 different Weatherhead valves from a well known big box auto parts retailer. They look the same, but each one of them had issues. One was extemely tight to turn, one turned well enough, but had no detents, and the third had galled threads that would have leaked if installed. I took them back and didn't even try to install them. The non PMA valve from Spruce might be just fine, but I was afraid that they would be no different than those from the auto parts store. I just bit the bullet and ordered the high $$ one from Univair.
Steve Pierce
BENEFACTOR
Graham, TX
The John Denver crash comes to mind.
Supertwotwo
Registered User
The Weatherhead valves are made by Anderson Brass in South Carolina, they are good quality valves, there are cheap China made copies out there that are junk.
Ursa Major
Registered User
Coeur d'Alene, Idaho
It could well be that the defective valves I got from the auto parts store were not 'real' Weatherhead valves, but poor quality copies.
Supertwotwo
Registered User
That is a sad story about John Denver, sounds like that accident could have easily been avoided. His medical was revoked because of a drug problem. He had just purchased the aircraft, the person that built it put the fuel selector in a spot that wasn't easily accessible while in the seat with the seat belt on. He took of low on fuel and ran out, tried to reach the fuel selector and crashed.
Supertwotwo
Registered User
That top valve is the Piper valve that was installed from factory on PA-18 from 1979 to 1981
Look up Piper service letter SL944
I don't know if that the plastic plug from Piper valve 77413-02 pictured in service letter 944 will work in the earlier Piper valves with the metal plug, I don't know if the valve bodies are the same or not, they look alike, if it does it would save some work of taking the valve body out.
On second and better thought probably not a good idea to mess with it, quicker to just take the old imperial valve out and change it for the new one, and not have to test and experiment.
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Steve Pierce
BENEFACTOR
Graham, TX
The valve was very hard to turn and had Vicegrips for the handle. Like most accidents there were multiple factors involved although I did not know and do not think his lack of medical was one of them. I have the original valve in my airplane and it works great but does require some maintenance so I am not trying to put down the Weatherhead valve just stating some facts.
S2D
MEMBER
Montana
Steve Pierce
BENEFACTOR
Graham, TX
Something I was reminded of and had forgotten about, some of these valves do not have the half moon shape on one side of the shaft for the handle indexing. More than a few serious accidents when the handle was misindexed.
Supertwotwo
Registered User
Here it is www.skygeek.com/piper-492-009-valve-fuel-select.html
There are none of the 77413-02 Piper valves around new anymore, but there are several new old stock Piper 492-009 valves around, and by the looks of the skygeek add linked above they are Anderson Brass valves, not sure what the change was from Piper part 77413-02 which SL944 mentions, to the one that replaced it later Piper part 492-009.
I picked up a 77413-02 off ebay out of a tomahawk being parted out and there are no markings on it to identify who made it, the Piper part 492-009 pictured in skygeeks add shows AB imprinted in the valve, that's Anderson Brass markings, that's the same marking the Weatherhead 6749 valve has on it available for $26 at Aircraft Spruce. I wonder if there is a way to tell who made the Piper 77413-02 that was used in 79-81 Super Cubs and 78-82 Tomahawks and available as a replacement selector valve for the metal plug valve 11383-04 in all Pipers.
Below is a picture of an opened up Piper valve 77413-02 out of a Tomahawk. The Piper valve and the Maule \ Weatherhead 6749 Anderson Brass valve look to be the same valve except that the Piper plastic plug is brown and Maule / Anderson Brass plug is white and the Piper valve stem is 5/8 inch shorter than the Maule \ Weathhead valve. The second picture is the one I got off ebay, neither one have the AB marking on them, wonder who made them?
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skywagon8a
MEMBER
SE Mass MA6
jrussl
BENEFACTOR
Madison, WI
I recently went down this same path and ended up going to the upgraded Dakota cub valve. But in another posting here I learned that the $26 valve from spruce is the same valve with a shorter shaft. Just swap shafts. A pretty cheap fix. when it comes to airplane parts.
There was also a lot of feedback regarding the plastic spools. Some said they were junk. But further in the thread someone astutely pointed out that the earlier plastic spools were nylon and had a cracking problem. The new valves come with a Delrin spool that solved the issue.
Hope this helps.
Jeff
Sent from my iPhone using SuperCub.Org
There was also a lot of feedback regarding the plastic spools. Some said they were junk. But further in the thread someone astutely pointed out that the earlier plastic spools were nylon and had a cracking problem. The new valves come with a Delrin spool that solved the issue.
Hope this helps.
Jeff
Sent from my iPhone using SuperCub.Org
