I recently bought a 4x4 6.9 from 1986. It's very hard to start, but when it does start it runs fine. I'm not familiar with these engines but it feels kind of weak on the throttle. As far as I can tell, it's getting fuel properly while cranking. It spits out white smoke that smells like unburnt fuel while cranking, and once started (on just a tiny hit of ether) it spits out a lot of gray smoke for a long time. The guy I bought it from said he couldn't find the 'y' on the IP gear, so he alligned it to the dot. I think that may be the problem, but it seems to run a little too well for the IP to be 180 off. I haven't had time for a compression test yet, but it kind of seems okay. Cranking speed seems fine, and all of the injectors are getting pressure. Whether warm or cold, it takes ether to start it if it is left to sit for five minutes or more. Should be able to get a compression test soon, I'll post the results to that, but in the mean time, I was wondering if anyone had any suggestions short of a new motor (Which I'm considering, seeing a buddy has offered me a 7.3IDI for $300.)
Thanks

 

Have you checked the glow plugs? Have a read threw this thread https://www.ford-trucks.com/forums/9...old-style.html this will tell you all you need.

 

Glow plugs seem to be fine. I think maybe it's got low compression, or maybe it's getting too much fuel while cranking because someone turned the pump up. Is that possible?

 

well,that's pretty hard to beat a good 7.3l for $300 bucks.however,you can likely fix the ol 6.9l for free.
here ya go;
"Talk about Timing!!"

and more tips:
https://www.ford-trucks.com/forums/1...pump-gear.html

 

She has a perfectly consistent 250psi compression. Is that enough to start and run at least okay?

 

not positive but i am pretty sure its supposed to be around 300 psi... but i am thinking a worn engine usually averages that and still runs pretty good

 

That's what I've read, I'm thinking that's not the hard start problem. While that's not what they like to have, that should be enough to start on glow plugs. I did find out tonight that I have a major leak in one of my return lines, I'll fix that as soon as possible and report back.

 

so is getting the timing right really as easy as the picture makes it look?

 

For anyone who may come along and find this, the IP was 180 degrees out of time. The above symptoms were all being caused by that timing issue. Fixed it, and now she runs like a champ. Thanks everyone!

 

congrats!

 

Glad you figured it out

 

I'm glad I read this and I'm glad you found your problem. I'm about to do mine and now I know what not to do and what to look out for.
My problem now is I rebuilt my garage door and now its to heavy for the springs. You figure. Boy, one problem after another.

Chet