New to us pa-12 and fuel system discrepancy between what we have and what the parts manual shows. I think the parts manual is in error. This is a 1946 pa-12 with header tank. Fuel panel placards say front valve is main tank shut off. Left tank. Must be on at all times in flight. Looking behind the panel shows the valve is just past the header tank in line to strainer. Same on parts diagram. Rear valve says , right aux tank on and off. And a visual shows it on the upper line as in parts diagram. But parts diagram shows that line goes to the left tank! Without taking interior and wing fairings apart I can’t trace were the lines actually go. Does anyone still have this old setup and know if rear valve is indeed on the right tank line?
Header tank fuel system
- Thread starter DennisB
- Start date
Paul Heinrich
PARTNER
Illinois & Wisconsin
Do your logbooks note any changes to the fuel system?
KJC
FRIEND
Clear Lake, MN
PA-12s came from the factory with and without header tanks. Both versions had 2 valves. Neither version had outlets on the forward side of the tanks. This caused some unporting of the fuel system and fuel starvation to the engine when low on gas and on final approach. I believe this was mainly a problem on the 1947 models without header tanks.
The PA-14, for which there was never a parts book published, had no header tank but did have a forward fuel line in the left tank. I believe this solved the problem.
From your description I believe your plane is likely plumbed the way it came from the factory. It works but it’s not ideal. I’d get rid of the header tank and use a Dakota Cub fuel valve with a both position and a forward left fuel line like a PA-14. Completely solves any problems.
The PA-14, for which there was never a parts book published, had no header tank but did have a forward fuel line in the left tank. I believe this solved the problem.
From your description I believe your plane is likely plumbed the way it came from the factory. It works but it’s not ideal. I’d get rid of the header tank and use a Dakota Cub fuel valve with a both position and a forward left fuel line like a PA-14. Completely solves any problems.
Last edited:
Gordon Misch
MEMBER
Toledo, Wa (KTDO)
Agree. My -12 has a forward port on the left tank and is headerless. Never a problem. It's placarded "left tank for takeoff and landing".
Thanks Gordon.Ok, there is no problem with the header system either. It runs on the header until you pitch up. You would have to be very low on fuel and nose down for a really long time to use up the fuel in the header. If people had problems when they removed the header they probably did not use left tank. Or some people removed the header on their own not understanding the reason for it and set themselves up for trouble. But my question was only about the discrepancy between the parts book and actual airplane
Gordon Misch
MEMBER
Toledo, Wa (KTDO)
"Neither version had outlets on the forward side of the tanks."
Yeah, when I bought my 12 in 1975 it was stock configuration - no header and no forward port in either tank. I wanted to see how it behaved on low fuel, and determined that even with quite low fuel it took serious down pitch to make the engine quit. Then it restarted promptly with nose up. Now I have Atlee tanks with a forward port, and am completely happy with the arrangement. The experimental -12 we're building is headerless, with Dakota tanks. The parts book discrepancy maybe reflects a little bit of indecision at the time?
Yeah, when I bought my 12 in 1975 it was stock configuration - no header and no forward port in either tank. I wanted to see how it behaved on low fuel, and determined that even with quite low fuel it took serious down pitch to make the engine quit. Then it restarted promptly with nose up. Now I have Atlee tanks with a forward port, and am completely happy with the arrangement. The experimental -12 we're building is headerless, with Dakota tanks. The parts book discrepancy maybe reflects a little bit of indecision at the time?
Similar threads
