Fuel Leak at Filter

[78Chev]

I have a leak at my secondary filter - but I don't have a stock set up. After my tank selector switch I have a racor filter, then an EP158 electric fuel pump, and then a secondary filter on my firewall which is the old type that used to bolt to the back of my 82 C 6.2 manifold (the little screw on type). I like this clean set up - it's all tight. But this secondary filter always weeps around the o-ring. I used to have the old square box filter there and it weeped too. I also had the Racor mounted there and it leaked. Seems like the electric fuel pump just puts out too much pressure. Should I use a different fuel pump? Also, can too much pressure bugger up the timing of the injection pump? Thanks for your thoughts.
Randy

[john8662]

How much fuel pressure are you running?

The injection pump ideally likes around 6-9 psi fuel pressure.

So you got the engine back in the truck eh?

[78Chev]

Yup, back in the truck and running. Didn't you use a chain instead of gears? I was tempted to do that but didn't. Sort of wish I had. I wonder if the timing issues and noise is related to the gears since they advance the timing by 3 degrees or so. I'll be playing with the timing for a while.

Not sure what my pressure is (don't have a gauge on it). I assumed the EP158 fuel pump would have the correct pressure built in.
Thanks.

[john8662]

Yeah, I swapped out the gears for a chain. I had too much advance.

But, I still haven't made sure that my injection pump is good (sitting on the shelf).

I'll see what I can dig up on that pump model.

J

[78Chev]

Did you have a chance to find the psi specs on that pump, John? Thanks for looking.
Randy

[john8662]

This is an AC-Delco EP158 correct?

If so, it's original application was on the 6.2 and 6.5, so I don't think this is the issue then.

It should be making no more than 9psi.

Check for any burrs on the fuel filter holder, use a little oil on the gasket when installing and see if that helps.

For some reason one of the units I disassembled has a smaller gasket around the threaded nipped the filter threads onto, all other units haven't had this. Does yours have this or not?

J

[78Chev]

Thanks, John.
I cleaned and went through the filter housing pretty carefully. Everything was in good shape. The thing seeps around the big gasket - there was no small o-ring on the threaded part. One change it did make to the housing (which isn't related to the leaking) is that I plugged the outlet, which is a hard-to-find 9/16 thread 1/4" fitting (like brake master cylinders) and drilled and tapped a port in the top center. Then I made a fuel line with JIC fittings for easy connection. Works great. Except for the gasket seeping. I'm hoping it will seal itself over time.

[78Chev]

Tim at Accurate Diesel just told me that fuel pressure from the lift pump is best for the injection pump at 5 psi +/- .5 psi. I want to check my pressure just after the secondary filter. What kind of fitting and gauge should I use? (I have installed a 1/4 NPT on the outlet side.)

Also, is there supposed to be some sort of pressure cutoff switch wired in when an electric lift pump is used?

Thanks!
Randy