Banjo Fitting on AFS Fuel Pump - help!

[SebsRV7A]

During my annual inspection, I found a leak in a pipe thread of my AFS fuel pump. I took the assembly out, took it apart, and resealed the pipe fitting. On reassembly and test, the banjo fitting at the bottom of the manifold is leaking under pressure.
How do I get this to seal? Are there particular washers to use to seal? I just reassembled it the way it came apart and crossed my fingers. Didn't work.

http://gallery.me.com/strost164/100037

Looking for suggestions! Thanks!

Seb Trost
RV-7A
4th annual inspection
Boulder City, NV

 

[Mike S]

Not seeing a banjo fitting in the photo----but there is a hole with a flat area around it where I would imagine a banjo fitting would be used.

The typical way I am used to seeing banjo fittings sealed is with a soft washer on either side of them. Copper, or aluminum I would suspect for fuel purposes.

Here is a typical setup.

 

[chaskuss]

Seb,
The two washers you removed act as gaskets. They must either be replaced or annealed every time the banjo is assembled. Are your washers made of aluminum [silver] or copper [reddish brown]?
Both types can be annealed [softened] to remove the work hardening they receive each time you tighten up the banjo bolt. However, it is difficult to do to the aluminum washers, as there is no visual warning of when they are nearing their melting temperature.
With copper washers, do the following:
Get an old screw driver, a propane torch and a cup of cold water. Place the washers on the blade of the screw driver. Heat the washers till they glow cherry red. Then immediately drop them into the cold water. This will anneal them. Clean the scale off of the now annealed washers using a ScotchBrite pad.
They can now be re-used. This process can be done numerous times to copper sealing washers. You can also find replacement copper washers at the local auto parts stores. They are used on many automotive brake systems, in the size you need.
Charlie Kuss

 

[SebsRV7A]

With copper washers, do the following:
Get an old screw driver, a propane torch and a cup of cold water. Place the washers on the blade of the screw driver. Heat the washers till they glow cherry red. Then immediately drop them into the cold water. This will anneal them. Clean the scale off of the now annealed washers using a ScotchBrite pad.
They can now be re-used. This process can be done numerous times to copper sealing washers. You can also find replacement copper washers at the local auto parts stores. They are used on many automotive brake systems, in the size you need.
Charlie Kuss

Thanks a bunch! I'm pretty sure they were aluminum, but I will look for some replacements at NAPA!

Seb Trost
RV-7A

 

[chaskuss]

Glad to help

Thanks a bunch! I'm pretty sure they were aluminum, but I will look for some replacements at NAPA!

Seb Trost
RV-7A

Seb,
Buying new washers is the easiest solution. However, knowing how to anneal the old parts comes in VERY handy when you are:

away from home, all the stores are closed, part is on Intergalactic back order [aka made of Unobtainium], etc, etc

FYI, an annealed part will be even softer [and seal better] than a brand new part. The edges of a new part get work hardened by the broaching operation used to cut them to size. I first learned to do this with English motorcycle head gaskets decades ago. Those old English bikes had head gaskets broached from 1/8" thick copper sheet. After a while, I learned to anneal even the new head gaskets to get the best seal.
Charlie

 

[SebsRV7A]

Seb,
Buying new washers is the easiest solution. However, knowing how to anneal the old parts comes in VERY handy when you are:

away from home, all the stores are closed, part is on Intergalactic back order [aka made of Unobtainium], etc, etc

I bought some new washers and annealed them. Cool process and the seal seems to be working so far. We'll see after I fly a bit with the cover off. With 15 connections, you never know if one is going to seep.

Thanks again for your help!

Seb Trost
RV-7A 4th Annual completed!
Boulder City, NV