I am new here and just want to say this website is great,its like an encyclopedia for the 1st generation cummins.

I have a growing problem with my 91. A few months ago i noticed it being a little hard to start. I've owned it about 6 years with no previous starting issues. Here lately i have plugged it up at night(30-35 degrees), and seems to start ok. It sat all day at work today with the temperature being around 35. It took about 10 times trying to turn it over and finally it started. It runs great after starting. I would appreciate any help from you guys so i can fix it before something gets worse. Thanks

 

Do you hear your grid heaters cycle?

 

How old is the battery ?

 

When was the last time it had a valve adjustment?

24.000 miles is the recommended.

 

At that temperature the grid heaters on mine really don't affect ease of starting. I have tried waitng for the WTS light to go out and starting as soon I turn the key and don't see any difference.
Del

 

Most of our trucks will start as soon as the first piston comes up. Shouldnt have to crank even one full rotation of the engine. I suspect you are getting some air in the fuel system. Do you have an original diaphragm style lift pump? Try pumping the little lever on there before you start it to see if it fires more quickly. The lever should be firm when its full of fuel.

Any smoke on start up? Other than that lovely black puff?

At those temps the only reason to plug the truck in is for you to get heat in the cab quicker. I had an 05 powerstroke that struggled to start under 30 degrees, but these ill mechanical engines will start fine in the single digits without being plugged in.

 

Grid heaters'


Just the fact that when you go to start it up, after it's been plugged in, and it starts fine, tells me that it's the grid heaters not working.

Check your solenoids to see if they're energizing when the key gets turned on when cold.

35 degrees is cold enough to cause hard starting issues.


FWIW,

In the factory manual, it specifically says to turn the key on, allow the heaters to do their thing, when the light goes out, to depress the pedal 1/2 way, and turn the key, immediately release the pedal. Allow to warm up.

Since I've been doing this procedure, vs just turning the key after the light goes out, it runs immensely better.


I had the same problem that you're having until I fixed the grid heater grounds and serviced my heater coils.


STarts and runs like a champ, now.



T.

 

well that day it was hard to start i saw a good amount of white smoke when it did start,that led me to believe there was a problem.i will try the suggestions you guys gave and see where what happens. i really appreciate all the help and info-i ran heavy equipment in the marines but my technical knowledge on diesel engines is limited-thanks