99 D-5.2-just went into hard starting-has always been a start-up at the 1st turn of the key.

pressure at the S Valve is 2lbs at the first key turn-(no run-just turned to get pump primed)-2nd key on brings up to about 25 lbs--and finally 3rd key on brings up to 50 lbs, then I start the D--if I don't do this it's pretty good bet I have to crank the engine awhile to get start.

when running the pressure holds at 50 lbs-constant-
after warm--and engine turned off--the pressure (as manual states should hold for 5 minutes) does not hold for 5 minutes--it drops to 0 within 2-to 3 minutes.

my thinking is the valve in the pressure reg. is bad--but if I'm dropping the tank to replace that--then I'm also going to replace the pump. Why? I have an 88 caravan that I have myself put in 5--yes-5--new fuel pumps because the old ones failed--

so if I drop the tank on the D for any reason, a new pump goes in to be safe

do you agree with what I think it is though?

thanks

 

Yes, it sounds like you nailed it.

 

+1 (2) sounds like you got it nailed with a bad check valve