bruceh

bruceh

Well Known Member
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Has anyone else experienced some slight leakage from the EFII fuel pump?

I have occasionally caught a whiff of fuel after the plane has been closed up for a while.

During my annual inspection, I needed to pull everything apart to clean and inspect the fuel filter. I noticed a bit of blue stain under the fuel pump, so I pulled it out.

IMG_6497-M.jpg


It looks like there is some weepage out of the recirculation check valve where it meets the end plate.

Here is a better picture showing that there is definitely some weeping of fuel.
IMG_6498-M.jpg


I decided to disassemble the components and see what I could do to make it leak free. I added some fuel lube around the washers and some Loctite 567 on the various threaded parts. Surprisingly, there isn't really anything preventing the leaks here. No O-rings or seals. Just a very tight fit.

IMG_6499-M.jpg


I got it all back together and put it in the plane and ran the fuel pump with the purge valve open. No leaks! Hopefully, this will fix things from fuel weeping.
 
So, you did not actually find the leak point? You probably have solved it, but, if it comes back, suggest you rig up an air pressure test with a good gage, valve on the inlet, and block off the other end and run 30 psi of air in there, shut off the valve and see if the gage drops. I found some tiny leak on my Vans style system with all of it's connections this way. Prior to engine run, I will do this for tank to servo.
Anyway, hope it is solved!
 
EFII pump

Hi Bruce,
We originally used crush washers to seal the pumps.
We found that an occasional pump would show a seepage after field use.
Most pumps do not have this issue.
We have changed over to o-ring washers which provide a much more positive seal.

If you or anyone else needs us or wants us to change out the crush washers to o-ring washers, we will do this free of charge,

Robert Paisley
 
Robert,

Thanks for the reply. That sounds like a good upgrade. I will have to get up to Cable have you swap these out.

Bruce
 
Field conversion to O-rings

rcpaisley said:
If you or anyone else needs us or wants us to change out the crush washers to o-ring washers, we will do this free of charge,

Robert Paisley
Click to expand...
Hello Robert,

Is it possible for an owner/builder to do the conversion to O-rings in the field (with no machining)?

Thanks,
Joe
 
o-ring washers

Hi Joe,
The O-ring washers simply replace the crush washers - no mod required,
If your pump was purchased in the last three years, it should already have o-ring washers.
Robert
 
Thanks, Robert. Good to know.

Occasionally I can detect a slight odor of fuel and my pump was bought4 years ago. So next condition inspection I'll disassemble it and install O-rings.

It would be helpful to know the size and quantity of the O-rings so I can have them have on hand.

Thanks again,
Joe
 
Joe, note that he uses the term "O ring washer" not "O ring".

Here is an example of 0ne kind of O ring washer---------but you should get the exact type from EFII, as there are a number of ways these are available.

or600.jpg
 
Thanks for clearing that up, Mike. I did not realize he was writing "O-ring washer" and assumed "O-ring".

Yes, I hope Robert will chime in with a specific source and part number.

--
Joe
 
Thank you, Robert. Now that I know the specs, I can find them at McMaster-Carr too and I like them because they'll ship USPS. Part number 93783A031 I believe.

--
Joe
 
Had the exact same problem a year or so ago. Found a little piece of debris under one of the seals (I had never disassembled prior). Removed, cleaned reassembled. No more leak.
 
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Shout out to Robert

Today I got up to Cable and met up with Robert. It took me about an hour to get the fuel pump out of the plane. It got updated and tested while we had some In-N-Out burger for lunch, then we headed back to the airport to reassemble everything. While I was up there I took my brother-in-law up for his first flight in the RV-9A. Oh, and the fuel prices there were lowered for the weekend. Paid $4.04/gallon!

Great customer service!
 
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