Starting issue

[joshua bebbino]

Hey guys, so I have a problem starting my 86 m1008, I've done a lot of research but can't figure it out, so here's the problem , when I go to start it cranks over and starts no problem but within 5 seconds it stalls, I do notice white smoke ( don't know what that means) after it stalls I've noticed it won't start no matter how long you crank it, it only starts after you let it sit for 10 or so min , and then it still takes alittle cranking. Once it does start and I drove it around I usually can turn it off and let it sit awhile and it will start right up but when I try it the next morning it does it all over again, starts right up then stalls, let it sit and it starts. I was thinking maybe air in the fuel lines? Or its losing its prime and it won't start again till the system repriimes. Any help would be greatly appreciated !! Like I said I did alot of research but there's no set answer.

 

[cucvrus]

My guess is that it is dropping the fuel. The diesel must retain complete prime at all times to start and run properly. It could be at the injection pump. Throttle shaft seals or behind the fuel filter then it is a pressure switch that needs replaced or eliminated. But you are dropping fuel prime is my guess. Look for wet spots the entire length of the fuel system. I would look under the cab also at the rear cab cross member. I have seen several with the fuel feed line rubbed thru up on the top. look for wet spots of fuel first then report back. Good Luck.

 

[joshua bebbino]

Thank you so much for answering! What do you mean pressure switch? I'm new to deisel engines lol I understand everything else and will check and post back, so I read somewhere and someone said something about a return on the fuel pump, they were saying if something was bad on that it could be sending fuel back ad it sits over night?

 

[cucvrus]

The entire system must be air tight. Nothing can leak. I mean nothing. It can leak air in at places and not make a wet spot. But the pressure switch is behind the fuel filter. Look carefully for a wet spot around the fuel filter. if it is wet with fuel anywhere it is leaking and needs to be fixed. The return line must also be air tight and leak free. The entire fuel system needs to retain vacuum and prime to work properly. These trucks are not new. Check the entire length of the fuel system. Good Luck.

 

[joshua bebbino]

Sounds good, I think I remember seeing a video of a guy and he filled that hole where that switch went with some kind of epoxy bc he said it was hard to replace since they were not in civlian models, I had orginal thought that was my problem bc I have read of people with similar symptoms fixing that switch and having success , thank you so much for the help!!!

 

[Tinstar]

Sounds good, I think I remember seeing a video of a guy and he filled that hole where that switch went with some kind of epoxy bc he said it was hard to replace since they were not in civlian models, I had orginal thought that was my problem bc I have read of people with similar symptoms fixing that switch and having success , thank you so much for the help!!!

I bought a new one on eBay where that port had been eliminated at the factory.
Mine started leaking like others have stated but always ran wonderful. Never sucked air.

Once you have it off you will see how easy it is to plug and reinstall if you go that route.

Good luck