Fuel Selector Valve

[6643]

You cannot use the 4 position valve unless you also have, or add the pipe connecting the two airspaces of the tanks. There is a danger fuel starvation otherwise.

Legally, certification requirements state that if you can draw fuel from more than one tank at the same time, the airspaces of those tanks must be interconnected.

[6597]

John,

I can start another thread if that works on my discovery, I was just adding to the thread. Yes, I realize that the plumbing is different but thought there may be those in the fleet that may be interested and may be following this thread (140A's and later 120-140's serial# 14340 and up).

[V529]

Univair makes a very modern FAA PMA fuel valve. It's paperwork includes all the engines for our aircraft listed on the Type Certificate. Not sure on their current pricing, but it's a great valve.

[bill_e]

Univair makes a very modern FAA PMA fuel valve. It's paperwork includes all the engines for our aircraft listed on the Type Certificate. Not sure on their current pricing, but it's a great valve.

I can confirm! Just had a Univair valve installed in mine and it has been working great so far. Took my A&P about an hour to install start to finish.

[n9661a]

The weather head valve ports are not the same as original also the Allen valve is left,
Off, right, off. So how are you guys making them work

[6597]

Look in the Neal Wright archive articles for fuel selectors August 2005 at the bottom of the Forum list. Simple handle modification for L-R-Off on the Weatherheads.

[6930]

The valve that was in my airplane was leaking. I noticed it because my needle valve in my Stromberg started to leak. I planned on pulling the plug out and lapping it to the body, but after I got it apart realized that the plug was not brass, but Delrin or some other polymer.

So, I ended up replacing the whole valve with the PMA'd version of the Allen valve from Aircraft Spruce. Cost of the valve was a whopping $549.00. The non-PMA'd version for experimental aircraft costs $200, but I just couldn't bring myself to install the non-PMA'd version for this important component in my airplane. Plus, I wanted my mechanic to inspect and log the installation and I didn't think he would do so with the version without the paperwork.

It was a very unpleasant chore to be honest. Not complex per say, just difficult because of the limited access and having to juggle the alignment of three different fuel lines. I installed new AN823-6D elbows and lined them up with the orientation of the old elbows before installation which certainly helped...but it was still a challenge. Orientation of the elbows aside, the fit was perfect.

Anyway, install went great. No leaks, valve works like a champ. It is a much better valve than that POS that was originally installed.

[8413]

Hi Mike,
Sounds like your old valve had the Jensen fuel valve STC which replaces the brass plug with one made of some kind of composite. My understanding is that it eliminates galling of the brass plug against the seat and therefore make the valve easier to turn and hopefully less maintenance.
Josh

[6930]

Hi Josh,

I expect you are correct. Though, as you noted, it was turning fine but the Delrin plug was scored and not leak tight. At this point, I am happy with the Allen valve but sure wish it wasn't so expensive!

Thanks!

[8413]

Thanks for your reply Mike. My 140A also has the Jensen fuel plug STC. So far, it is going good. Time will tell I suppose. I hope your issue was due to neglecting to polish up the seat prior to assembling the new plug and not some kind of failure of the plug itself due to the material used. I have a Marvel carb so it typically doesn't leak fuel out of the carb even with the fuel selector on either or both tanks. So, I'm not sure how I would know if I have the same issue unless it leaks out of the valve stem.
Josh