Question for all 6.5 diesel Gurus

Lift pump is getting weak and out of time

Brand new lift pump

It's winter time... Did it act the same last year during colder weather?
The lack of smoothness is most likely 1 or more cylinders not firing on the first few rotations while the other 7/6/5 are.

You can use a multimeter to check the resistance of each glow plug (remove the splash guard on the passenger side, I think you need to remove the driver's side as well, can't remember). Disconnect the wiring to the glow plug then test. Look for one that has a high/open compared to the others.

You can also cycle the key more than once to time the plugs a second time for additional heat. Had a PSD that about half the plugs were shot (gotta pull valve covers and it's a bigger job than on the 6.5L or the LBZ). It was a rockin, shakin, smoke puffing ride for the first few seconds.

newman fulltimer wrote:
Lift pump is getting weak and out of time

Yup. Chris is right. I Had a '93 & a '98 with 6.5s. Injector pumps were good for 60 -90k miles. Good starts until colder weather, then weak rough starts. Expect 2k to rebuild it.
6.5 weak points I saw are the injector pump amd in later years webbing cracking in the crankcase which leaks antifreeze into the oil. Almost makes me wish my '98 was a Ford or Dodge.

Almost

Injector pump is perfect. Lift pump is pulling from tank perfect also. I think I have to replace my lines that may have slight leak off of the filter housing. Pump is turned up and truck is chipped runs smooth and strong and gets me 20 mpg highway with a 410.

Another common problem with the 6.5 Turbo Weasel is the PMD and Injector pumps get pretty weak.

Good luck...

Mine used to pop off instantly but now makes LOTS of noise! :h

What did you do put a turbo on a 6.2?

All glow plug wiring good? Have you replaced the injectors? My '96 6.5L hated any glow plugs besides AC Delco for some reason. How long does the Wait to Start light stay on when you cycle the key?

No have a turbo 6.5