rebuild fuel selector valve

DrDave · #1 03-07-20, 12:07 AM

Here is a picture of the o-ring that sits on the shaft of the selector lever. This could be a source of leakage.

wslade2 · #2 03-07-20, 02:33 AM

oh my goodness. that internal clip that holds the spring does look like it will be a problem. I wonder if an internal c-clip would work in it's place.

DrDave · #3 03-07-20, 08:28 PM

I will measure the thickness of it tomorrow. I don't have the right caliper to measure the inside groove diameter where it seats. One thing I would encourage is to take pictures and mark where the tubes go before you remove it.

Dave

TomM · #4 04-10-20, 10:33 PM

I was wondering if there was any follow up to this posting. I got to fly my skymaster for the very first time today.....and what a machine these things are!!!! What I found out was that when we were flying on the main tanks, the front engine would also pull fuel from the aux tank. 2.5 hours of flying time used 8 gallons out of the left aux tank. I moved the selector valve around a bunch of times to see if there was something stuck in it that could get worked out, but used about the same out of the aux tank on the next 2.5 hour flight. I am thinking the balls and seats have corrosion on them as was shown in the pictures in the post. I didn't want to have my mechanic rip it apart until he was certain he could replace those clips if one were to be broken or lost in the process.

Also, in the post below there is mention of B and S in Wichita. Did you ever reach out to them regarding rebuilding the valve? Just trying to wrap my head around all the options.

Thanks much guys!!!

JAG · #5 04-12-20, 11:17 AM

Tom,
I am not saying that it could not be some internal corrosion or problem in the valve, but if you have not verified, just double check the rigging of the valve. One small panel on at the wing root and a mirror, and you can verify that the valve is in the detents and rigged properly.
Jeff

wslade2 · #6 04-12-20, 02:28 PM

Ended up leaving the valve alone. (We got sidelined with more critical issue of flap-trim interconnect cable seizing in its sheath and restricting trim control.) It's on a future project list when can stand risk of long term disabling the valve. But have been concerned about what you experienced. Likewise agree about checking the rigging.

TomM · #7 04-13-20, 07:36 AM

Thanks guys! I will check the rigging and go from there - that is a good idea o verify the easy stuff and go from there. Thanks again!

cessnadriver · #8 04-13-20, 10:57 AM

wslade2.
FYI, you CANNOT just replace the original clips with a C clip from a assortment of clips. That would be illegal. I'm not trying to be a know it all but as an A&P I know there are rules in the FARs that prohibit this kind of modifications. If the original clips are not serviceable and hard to come by you may have to buy a serviceable selector valve and replace the whole valve?? Has anyone tried contacting AIRBORNE the original valve manufacturer, for the clips?
Just a thought.
Regards, BILLS

Trippster · #9 04-21-20, 07:46 PM

Has anyone used McFarlane to rebuild their fuel valves? I spoke with Dave 2 days ago and he told me they can rebuild them now. He said it's mostly labor, but they do fabricate a few pieces. He mentioned somewhere in the $600 range.

We're having some issues and may need a rebuild also.