1. Home
  2. Chevrolet Trucks
  3. Re: My 96" 6.5 Diesel stalled.. any ideas?

Re: My 96" 6.5 Diesel stalled.. any ideas?

Hi!

I'll bet you have air trapped in the fuel system. This can be a common problem and your truck's manual has instructions on how to solve it. Somewhere around your fuel filter there is a bleeder valve IIRC.

I had the unfortunate situation of running my '84 out of Diesel fuel one day. (Actually, little brothers twiddled with the fuel tank selector switch...) It restarted, but for the longest time the throttle was extremely touchy and "unpredictable" because air must have been sucked into the fuel system. After enough driving it seemed to have gotten rid of the air, and my "water in fuel" light did come on once shortly afterward.

If you don't have the manual, I would assume there are web sites that might tell you how bleeding the air out of your fuel system is to be done. If you can't find anything on how to do this, let me know and I can scan the manual from my '84 truck...not sure if that would help, but IIRC the 6.2 and the

6.5 are pretty similar engines...
Reply to
William R. Walsh
Loading thread data ...

Someone told me to try the bleeder valve at the filter. I tried unscrewing a little and turning the engine for a while and no fuel came out. I then totally took it off and still no fuel came out. It did try to hit quite a few times doing this but never would fully start. I was told that fuel definately should come out of this bleeder valve. Since it is not what could be the problem? I was told the lift pump would be it. Any ideas? Thanks for any advice!

Reply to
Pudpuller

Thank you for your detailed response. I did what you described and no fuel came out. I will replace and follow up my results. Thanks again for the detailed response! It is very much appreciated!

Reply to
Pudpuller

:snip a lot of good stuff

Please note, that the liftpump is supplied with 12 V through an oil pressure switch (when the engine is running), that is prone to failure. Before buying a new liftpump, check the voltage supplied to the lift pump. This *must* be done with the liftpump connected. If you disconnect the pump while checking the voltage, the "no load" situation will give a false reading.

This can be done in at least two ways:

  1. Using very small needles, to punch through the wires to the liftpump, and connecting a voltmeter to the needles.
  2. Insert a very small wire in the plug to the liftpump and connect the wires to a voltmeter.

If there are less then 12V to the liftpump, the oilpressure switch is defect. If you got 12v and no operation on the pump, replace pump. After you have replaced the pump, meassure the voltage again. It is entirely possible for the oilpressure switch to "be allmost" working, in which case you still have a problem.

Good luck,

Regards, Bjarne

PS, just to clearify : When the key is turned to "start", the liftpump is supplied with 12V through the liftpump relay. When the engine is running, the liftpump is supplied with 12V through the oilpressure switch.

Reply to
Bjarne

Thanks guys for the input. It was indeed the lift pump. I went through the steps after the new install and fuel was flowing. I then tightened the bleeder back and it started right up. I drove it around the block and all seems fine. I really appreciate your time in responding and helping a non mechanic fix this. Now I can go to the lake tomorrow! Woo Hoo!

Reply to
Pudpuller

Glad to be of help. These trucks are not that hard to diagnose or fix. Almost any problem you could have has already been seen by someone else. The two most common issues tend to be the Fuel Solenoid Driver (FSD, aka PMD or Pump Mounted Driver) which is the black box that is the heart of the fuel injection pump, and the wiper circuit control board that controls your wipers. I've had plenty of experience with both.

Cheers - Jonathan

Reply to
Jonathan Race

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.