6.5 Runs rough at 2500 rpm

[mrbornery21]

I have a 1995 1 ton 4x4 6.5 turbo diesel, manual trans, with a 1997 engine with 9000k. The truck runs rough at 2500 rpm. compression checks out, fuel filter has 3k, injectores 2k.
Im thinking lift pump, but it checks out with the truck running it fills a gallon jug in no time. havint checked fuel psi. the truck runs smooth from idle to 2000 rpm then has a slight miss,but gets real rough at 2500 rpm then starts to smooth out after 2500 rpm. The only problem I have with the truck besides running rough at 2500 rpm is when I try and start the truck in 32 degree cold mournings during my hunting trip the truck tries to start when cranking, then i have to stop, turn the key forward then I hear the lift pump kick on for a while then once the pump stops i can start the engine fine.

Im thinking the problem is the LP or crank sensor, or timing. seems like a fuel delivery problem. there is no smoking issues

Just seeing if anyone has had simular problems and what fixed it

[More Power]

- I'd want to eliminate excessive timing chain slack or a damper prob before suspecting something else. Most other electronic or injection system component would likely affect the engine across more of the rpm range...

The cold starting prob could be a separate issue.

Jim

[mrbornery21]

Hey jim the 1997 engine was bolted to a automatic trans, so when installing the engine in my manual truck, I put a brand new clutch,pressure plate, through out bearing in cause the old clutch was gone. and I had the fly wheel turned/ resurfaced by carquest cause it really needed it. Im just wondering could the imbalance be coming from the fly wheel, it is not a dual/mass but a solid fly wheel. Everyone I talk to says that the fly wheel should stay balanced after a resurface and I shouldnt worry. And last but not least I used the H dampener from the automatic not the original H dampener from the manual. I called every parts house and the part # for the manual and automatic dampener are the same, Maybe the 1997 one is bad. Whats your thoughts?

[More Power]

Hey jim the 1997 engine was bolted to a automatic trans, so when installing the engine in my manual truck, I put a brand new clutch,pressure plate, through out bearing in cause the old clutch was gone. and I had the fly wheel turned/ resurfaced by carquest cause it really needed it. Im just wondering could the imbalance be coming from the fly wheel, it is not a dual/mass but a solid fly wheel. Everyone I talk to says that the fly wheel should stay balanced after a resurface and I shouldnt worry. And last but not least I used the H dampener from the automatic not the original H dampener from the manual. I called every parts house and the part # for the manual and automatic dampener are the same, Maybe the 1997 one is bad. Whats your thoughts?

The flywheel balance should be fine after resurfacing, though you should be running the matching pressure plate and clutch plate made for the single-piece FW. These components were re-designed to work with the new single piece FW. The 6.5 dampers are the same for both man/auto.

Take a look at the recent article on the Fluidampr (http://www.thedieselpage.com/features/fluidampr.htm) to see how to identify a bad 6.2/6.5 harmonic damper.

Measuring timing chain slack can be done by removing the oil fill pipe on the front of the engine. Then using the timing mark on the damper to measure how many degrees you can rotate the crank (using a flexhandle & 15/16" socket on the damper bolt) before you see the gear on the injection pump begin to move. 2 degrees would indicate a new timing chain. 3 degrees is approaching midlife, and 4 degrees or more would indicate a chain out of tolerance. Excessive chain slack can produce a resonance at specific RPMs, which results in a more erratic injection timing.

Jim

[mrfixxall]

I have a 1995 1 ton 4x4 6.5 turbo diesel, manual trans, with a 1997 engine with 9000k. The truck runs rough at 2500 rpm. compression checks out, fuel filter has 3k, injectores 2k.
Im thinking lift pump, but it checks out with the truck running it fills a gallon jug in no time. havint checked fuel psi. the truck runs smooth from idle to 2000 rpm then has a slight miss,but gets real rough at 2500 rpm then starts to smooth out after 2500 rpm. The only problem I have with the truck besides running rough at 2500 rpm is when I try and start the truck in 32 degree cold mournings during my hunting trip the truck tries to start when cranking, then i have to stop, turn the key forward then I hear the lift pump kick on for a while then once the pump stops i can start the engine fine.

Im thinking the problem is the LP or crank sensor, or timing. seems like a fuel delivery problem. there is no smoking issues

Just seeing if anyone has had simular problems and what fixed it

injector pump timing,sucking air or inj pump is going out..hway people dont realise is if you hold your fot on the throtle to long it resets the injection pump timing back to zero,so on those cold days dont put your foot down to the floor for no longer then 10 seconds..