EFII fuel pump leakage

[bruceh]

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.



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.


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.



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.

[BillL]

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!

[rcpaisley]

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

[bruceh]

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

[Joe]

Originally Posted by rcpaisley

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

Hello Robert,

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

Thanks,
Joe

[rcpaisley]

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

[Joe]

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

[Mike S]

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.

[Joe]

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

[rcpaisley]

The pump uses six 10mm (or 3/8") o-ring washers, also known as Stat-O-Seals.
These are common parts. We also have them in stock.
We are happy to add them to any older pump free of charge.
http://www.summitracing.com/parts/rus-683880

Robert