tqracer

here is my problem. i installed a 97 motor into a 85 chevy 4x4 truck. this was done over 2 years ago. about 8 months ago the return line sprung a leak. got out and repaired it. went on down the road about 5 miles the pedal got real soft, lost power then died. would not start right up. let sit on side of road for 2 or 3 min. fired up with normal cranking and has run fine since untill last sat. same thing happened again. after this time i chaned fuel filter added some fuel cond. and checked the spring on the pop off valve for the return. also added extra trans fluid to the fuel. drove the truck wendsday night to the race no problem. coming home from track down the interstate the motor lost power and started to miss. got off my exit pushed in clutch motor revved up.let clutch out pushed back in motor died. tried to restart it would not. let the truck coast down the road about 4 blocks to pull off road hit the key started right up drove it 20 more miles no problems. only time this stuff has happened is when i have been pulling a 24 ft trailer. i can not see the suction line being clogged by something and falling off when motor dies because you dont have to crank the motor more than 1 or 2 times for it to refire. hate to replace inj. pump if thats not the problem. motor has about 225,000 miles on it. stock but the timing has been bumped up.

infidel

I would start by replacing the overflow valve.

Precision Diesel Injection and Turbo Inc.
Marty Tompkins
toll free 888-734-7349
$24 + $5 shipping and handling.

And no more ATF in your fuel. It isn't designed to burn and can damage the engine with ash deposits. It's use is a leftover from the days when ATF was just oil and designed for diesel additives weren't widely available.

tqracer

what should you add to fuel. i was told trans fluid by a guy who works at cummins.

DZLPWR

If its manual tranny fluid, i dont think its as big of a deal as ATF.

MCummings

My manual tranny IS motor oil....

Maybe the shut down solenoid?

It's just a shot in the dark.. Bill really knows what he is talking about though..

Merrick

98rammer

it could possibly be the fuel lines. they tend to crack and suck air (you wont be able to see the cracks usually). it's often the return line too. how did you repair the leak before?

like merrick said, it could possibly be the fuel shut off solenoid, or the relay.

you may also want to check fuel pressure. the return pop off valve usually doesn't cause stalling conditions, just low fuel pressure/ low power conditions and extending the spring doesn't always work.

Tom

tqracer

i replaced the rubber line down to the metal return line. fuel shut off does not have a relay on it.

Redleg

Your certain the fuel line is good for diesel? The inside diameter is big enuff? If not made for diesel, could it be getting week and collapsing when the pump is working hard? Haven't bought fuel line in awhile, they're all probably multi- use anyway, just thinking out loud.

infidel

Redleg, you are correct, unless you specify diesel rated hose you will most often get gasoline rated. It eventually melts.

tqracer, you seem pretty mechanically inclined, instead of an overflow valve tap a 1/8'' port into the top of the injection pump inlet banjo bolt and use it to measure fuel pressure. You will need a needle valve or gauge snubber to dampen pulsations.
You should see no less than 18 psi at idle and 24-35 at full throttle.


Needle valve installed in banjo bolt

tqracer

the truck had a 6.2 in it to start with. i used line thats made for diesel. can i us the port that is on the discharge side of the fuel filter houseing. thanks for all the help.

infidel

The port I think you're referring to is the bleed screw. It can be used but is a small metric bolt size. An adaptor is available from TST but costs $25 and is for temporary use only. You would have to be very crafty to make one yourself. Tapping the banjo is fast and cheap.

http://www.tstproducts.com/service_tools_trial.htm

Partsman

My 98 has two hoses for return one from the pump to a metal piece behind the fuel housing about 8" long and then form that piece to the frame did you change both?

tqracer

i will have to look but i did not see any rubber line behind pump. i replaced hose from the metal line that is in front of fuel filter to the frame back to tank.