Please help engine trouble

[playinwitmatchz]

6.9 idi idles fine and all but try to drive it runs like absolute crap. Any ideas? Think the injection pump needs adjustment or is it maybe it tossed a piston or two.

[FordGuy100]

If its tossed a piston or two, it would hardly idle.

My bet is a fuel issue like you said. First thing, replace the fuel filter. Its a maintaince item anyways so might as well do it.

If that doesnt do anything, we can go from there.

Does it smoke under throttle? White, blue, grey, black?

[playinwitmatchz]

I'm looking at buying the truck, forgot to mention it. Looking at how the kid wrote his posting I'm betting it's a bad fuel filter and old as hell fuel. Maybe even gelled these past few days in the NE. Anything I should really look for engine trans wise? It's an 86 f250 ext cab

[FordGuy100]

Just your standard truck lookover. Check the coolant, for oil, or coolant in your oil. 6.9's have fairly weak head gaskets factory, so they do blow out from time to time. Head gaskets plus head studs (ARP) are a good upgrade.

As far at the tranny, smell the fluid, see if it smells burnt.

[playinwitmatchz]

Ok. Do the 6.9s smoke much when they are cold. It's currently 20s with some pretty heavy wind. Smoked white from one of the stacks. Idk how he has them run but if it's strickly right bank could it just be it's cold unburnt fuel or coolant

[FordGuy100]

Was that on a cold start? If so, then that could be normal. How much and how long?

[playinwitmatchz]

How many fuel filters do I have on a 6.9. I sourced a Donaldson spin on from work but hear that there is another one. Donaldson doesn't list it referenced to ford but it is when you reference the 6.9 diesel. Part numbers would be even better if possible

[playinwitmatchz]

Also. Is there an extra 2 or 3 inches in length for the spin on filter? Donaldson has a spin on with water drain that's about 9 inches tall. Has a 10 micron rating over the factory rated 20 micron. I would look mysel but the truck isn't in front of me at work

[FordGuy100]

6.9's have one fuel filter, as do 7.3 IDI's.

As far as that 9" tall one, its to large, and wont work I'm pretty sure.