Engine/Transmission (1994 - 1998) fuel pressure ?'s

[Heepdriver]

Just installed a fuel pressure guage and have while running at at least 1200RPM and up 33PSI of fuel pressure. Is there such a thing as to much? it goes to almost 40 when I coast. I have noticed that my return line is dented and slightly pinched under the truck, truck was totaled, but the supply line is good. Did I streach the OF valve spring to much?



thanks

 

[Johnstra]

Unless your return line is badly pinched I suspect you overstretched the OF valve spring. I don't think it's going to hurt anything though. Joe G. overstretched his and he says his hits 40 on occaision too and he's had no problems.

-john

 

[WaynesWorld]

Just installed a fuel pressure guage and have while running at at least 1200RPM and up 33PSI of fuel pressure. Is there such a thing as to much? it goes to almost 40 when I coast. I have noticed that my return line is dented and slightly pinched under the truck, truck was totaled, but the supply line is good. Did I streach the OF valve spring to much?



thanks

Heepdriver,



Your heep is the envy of many a 24 valver :-laf



No its just fine, now where are those really big injectors at ??



WAYNES WORLD

 

[biggy238]

Ran mine too high to speak about with no ill affect. I liked the way mine ran at 35psi.

 

[bmoeller]

If the pressure is too high, it could crack the canister (if you had a '97 up truck with the element type fuel filter, anyways) or also in the same case, the o-ring that seals the canister, can get pushed out and leak. Been there, done that.



In your case, it is probably going to be OK, but the spec is- 8-24 psi at idle, 28-36 at 2000 rpm with no load.



I would shorten the spring in the OF valve and depending on how bad the line is pinched, replace it.

 

[Heepdriver]

My Dodge is not the Heep

Heepdriver,



Your heep is the envy of many a 24 valver :-laf



The heep is for sale in the other vehicles catagory of the classifieds. Blew up the motor mud boggin. Man that truck was fun when it was runnin. I've had it standing on two wheels going down an embankment pulling trees. We used it to pull forklifts and even managed to pull a 5ton military truck out when they got stuck on one occasion. But all good things must come to an end and it needs a new home.



The Dodge seems to run 33 to 35 PSI of fuel pressure at normal cruise (65 MPH) light load (750 LBS in the bed), only really dips below 30 on third going after it . No leaks so far and running good other than I started messing with the timming again and well I better go back and mess some more.

 

[Joe G.]

Did I streach the OF valve spring to much?

Ya gotta be careful with that spring. A little bit goes a long way. You are running less pressure than I am so you should be ok. If I lift with the TC locked up at 70 it will peg my 40 PSI gauge every time. High 30s are not unusual just running down the road. I thought that the spring would relax a little after a few miles so I would be ok. That was 150K or so miles ago. No sign of relaxing yet.

 

[Heepdriver]

Thanks everybody for the good info and numbers. I am going to leave it be. Other than adding another needle valve in line to smooth out the needle a little more. I guess the pressure is not to high to worry about. Thinking of getting a 4KGSK and some valve springs next, now that I know I have the fuel to suport it.



Oh by the way the fuel guage set up here cost me about $30.



6'6" 300 PSI fuel line made up at Asheville Hose w/swivel fitting $13.

1/8" NPT 60 PSI guage (nothin special, but I'm assured of acuracy, they can see fuel directly and the fitting is on the back) $9

1/8" NPT needle valve $7

1/8" NPT brass adaptor $1

these numbers are roughly correct I don't have the reciepts here.



Tips I would suggest doing when installing:



Install the swivel fitting at the injection pump. ( if you put it here the first time you need one less adaptor and its easier to work on.



Wrap the fuel line with rubber hose anywhere it will contact anything. The pulsations will rubaway the outer layer of the hose. And then zip tie it in place to insure it doesn't go any where.



Just drill and tap your own bango bolt, need a Q drill bit I believe and an 1/8" NPT tap. Take your time, drill from the in side out.



As far as where to put it, I finaly got rid of my O/D SW on the dash. Used a rubber body grommet about 1 1/2" ID and 2" OD. Removed the SW and filler plug, then cut out the material inbetween.



The more guages I have the happier I am.