I have a 1970 Jaguar XKE with dual Stromberg carburetors. I recently had to replace the "Fuel Pressure Regulator". I purchased an aftermarket regulator which has adjustment for 1 psi to 5 psi. I am uncertain of the correct psi setting for my car. I am also not certain of the output of the fuel pump. I set the regulator at 1.5 psi and it seemed to work fine for about 10 days. Now the car is cutting off from lack of fuel. I am having to use starting either to get it started. I have tried different psi settings but it doesn't seem to correct the issue. Any thoughts?

 

Welcome to the forums falderfer,

I've copied this post from your Intro for advice fom members with the same model.

Graham

 

Hi Falderfer,
I don't think you are supposed to have a fuel regulator if you're running a stock fuel pump. I know the Series I doesn't with a stock pump.

From what I can find in the shop manual the fuel pressure should be ~2psi.
Cheers,
Bob

 

Thank you Bob

 

Yes I have done a lot of research to find the right pressure setting for XKE s It seems 3.6 psi is ideal for 3 SU equipped cars and 4.1 psi is ideal for twin strombergs.

Now here is the problem, most aftermarket suppliers send out a round plated fuel pressure regulator that has the increments printed around the edges. This device has a diaphragm
and a valve and spring inside, after setting to what you want it sometimes works for a week and sometimes fails right away, by not delivering any fuel ! After waiting for a few minutes
the engine runs again. Other times rapping it on the side with a screwdriver makes the regulator start working again.
All this with three of these round regulators (they are made in China) and the same fails continue. So I bought a Edelbrock fuel pressure regulator (low pressure kind). and although
this is a lot more expensive $49. when it was set up with an accurate gage, in my case 3.6 psi it has never failed !
I have built a lot of cars over the years(59) and have experienced many failures with these round pressure regulators but since using the better made adjustable ones with a screwdriver
and lock nut setting adjustment these maintain the right pressure.

US made engines use a higher pressure setting 7 to 15 psi and English cars require a much lower range, it depends on the lever length and size of needle valve seat, size of float
that your carburators have so that the pressure setting will keep the carb full without overcoming the needle valve in the float bowl.

 

Thank you everyone for your responses in regards to the fuel regulator, it seems to have self-corrected itself. I do have another question I hope someone can answer. Can anyone tell me where to find the radiator fan relay. I am also wondering if both fans are supposed to run continuously while the ignition is turned on or are they suppose to alternate?