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Leaky SUs on E-Type

billca

Senior Member
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The car is a '67 E-Type.

The problem is leaking carburetors.

The car has been sitting a long time while I completely rebuilt the brakes.
I also rebuilt the carbs because they were all gummed and had some rusty/jammed parts. A couple of them also leaked from the fuel bowl overflow.

The needle/seats in the fuel bowls were replaced with the type that have a spring in the needle. Float levels were set with the needle springs NOT compressed.

There was still leaking from the fuel bowl overflows. The fuel bowl needle/seats were then redone with a tiny bit of thread sealant and more torque when tightening.

The fuel pump pressure was checked and is 5 psi instead of the recommended 2.5 psi.

The fuel bowls no longer leak at the overflow but there is a bit of fuel coming out the jet, as is the fuel bowl level is too high.

My questions:

1. Is 5 psi enough pressure to cause all of this problem? None of my repair manuals mention the effect of excessive fuel pump pressure.

2. Are the spring loaded float bowl needles more susceptible to high pump pressure than the solid needles?

3. Am I correct in setting the float level with the float needle springs not compressed?

4. Is a combination fuel filter/ pump regulator available and do they work well? In the back of my mind is such a gadget but I don't recall if they work and are still available. (No, I don't want to remove and adjust the in-tank pump if I can avoid it!)

Thanks for the help any of you can provide.

I look forward to getting the car back on the road, hopefully without a trail of expensive fuel along the road!

billca
 
'k Bill... sorry you haven't had a response sooner.

1) Yes, 5 PSI will unseat 'em.

2) One more change of needles: get the Viton tipped ones.

3) Yes, as far as float height is concerned... but see #2

4)What kind of E-type have ya got there? The *SU* fuel pump was located in the right rear inner panel of that car inside the boot, behind a trim panel. No "in-tank" pump ever came on a '67 E-type that I'm aware of. And SU pumps ran at lower than 5 PSI.
 
Hello Billca,

Did you use the proper notched fiber washers for the fuel bowl lid?
If this does not breathe you will have this sort of issue.
 
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