92 - M1038 Ignition Issue - Suggestions

[Lawdog734]

Gents - I've been flipping through the TM's and have found that the information is great, but it's not exactly helping me out with diagnosing my particular problem. So I'm hoping that I can get some input from you before going on a wild goose chase and throwing money at parts that might not necessarily need replacing.

I've got a 92 M1038 that I recently picked up - overall, I'm very pleased and have found no heartbreaking surprises just yet on the short drive onto the trailer and a quick spin around the pasture when I got it home Monday evening. I did find that one of the power steering hoses has a pinhole in it that is spraying PSF out of and needs to be replaced, but it's got a straight body, all the lights work and the fluids are all at the proper levels and actually look like they were changed just prior to going to DRMO. Beyond fluid checks and general inspection, I only have about 45 minutes of daylight when I get home from work before it gets dark, so I won't be really digging into it until this weekend.



The issue that I'm having is with starting it. When the ignition switch is turned to the "RUN" position, the "WAIT" light flickers once and then goes out - it's a fast enough flicker that you'll miss it if you're not watching. When I attempt to start the vehicle when the engine is cold, it's a solid 15 seconds of cranking before it starts. While cranking, dirty white smoke is coming from the exhaust, which leads me to believe that it's unburned fuel. Upon ignition, I get a heavy cloud of dirty white and then dark gray/black smoke (more unburned fuel and then I'm thinking fuel rich exhaust smoke) for a few seconds and then the exhaust blows clear. If I shut it off and start it up a short while later, it fires right up - but again, I have that dirty white looking smoke (for a second or 2) until it actually starts then dirty white and dark gray/black smoke then clear. If it sits overnight - I'm back to 15 seconds of cranking.

I intend to change the fuel filter this weekend and I know that it would be wise to change the glow-plugs as well. My big question is - do I need to look elsewhere given that the "WAIT" light isn't functioning like it's supposed to? Is it possible that the glow-plugs aren't getting enough voltage to heat properly, but after cranking for as long as they do it eventually has enough heat to function and fire up?

I'm not a mechanic, but I do know how to turn a wrench and could use some guidance so I don't get myself into trouble.

 

[Retiredwarhorses]

Being this has been covered at least 100 times in the last 6 mos...here it is one more time...LOL

your problem is your Engine start box is bad, and/or your glow plugs are bad. The reason for the long crank and white smoke is that the glow plugs aren't igniting to assist in a cold start. The white smoke is excess unburnt fuel....you need to know how a diesel works, it needs fuel, air, compression and heat to work, that initial heat comes from the glow plugs.

you will need to remove all the glow plugs to check them all, I say this becasue if the Engine start box is bad, they have a habit of taking out 1 or more plugs....chances are, you need at minimum a new Engine smarty pants box with temp sending unit.