low fuel pressure

Is it the later pump with the Allen Key for the spring or the old pump with a 5/8 socket size?
When you fitted the new Pump assuming its the Allen key type did you buy a spring kit also as the new pumps come with the old springs?

 

the new style with the allen head plug.

 

no i didnt get the spring update i just shimed it.

 

Then that will make a difference as the spring is longer

 

do you know what the part # is for the newer spring?

 

here u go.

 

dang computer cant open file. i think i found it part # 339-4983 i'll try this tommorow and get another gauge to see if there is a difference. one thing i may have not said was that when im on a hard pull under load at about 1700 rpm it will studder like it's starving for fuel. keep it under and it seams to run ok but with a slight vibration like it isnt getting enough fuel.

 

This is where you need a Fuel gauge in the Cab to see if its maintaining fuel pressure during a long hard Pull!!

 

it's on the list, but it's a long, long list!

 

If it's the Allen style pump you probably won't be able to shim it, from what I know installing the correct spring is the way to bump the pressure in this style of pump. The old style are the shimmable kind.