Smoking Chevy

[merryman]

My sons '94 Chev. 6. 5 diesel suddenly started smoking very heavily on start up. In a little while it clears up and runs fine till next start up when it smokes heavily again.

Any one have good ideas what the problem might be?

Thanks



Vaughn

 

[JoeyD]

How many miles on the glow plugs? That would be the 1st to check. I changed mine out at 50k and 3 of them looked bad. Hope this helps. If not I can ask on the Diesel page for you.

 

[juicedcummins]

Glow plugs ,lift pump pres not just the noise of it running. If not running check oil pres switch for output to lift pump. It's been a long time but I believe th 94"s still used the old oil pres switch.

Hope this helps.

Plugged fuel filter will also do this.

Simple test for glow plugs is to use a test light and leave them in the head. Put the gator clip on the + terminal and If it lights up it is good. {I hope I haven't got it backwards} you will be able to tell and it will not hurt anything. If he has 3 plugs burnt out I would be very suprised if it would start at all without being plugged in.

 

[jwarner]

I experienced the same problem a few months ago with my wifes 95 6. 5 turbo Suburban (short trip driven for 2 years). I checked all injectors for amperage, changed fuel filter and still the problem of smoke on start up was there. I went through three gallons of P&S fuel additive on a trip from Illinois to Alaska. Problem was gone. I believe that the injector tips were dirty and dribbling on start up. The four days of running cleaned everything up. Engine now has 110,000 miles on it and has never run so good getting 17 mpg loaded up heavy.



The 94 6. 5 turbo does have the oil pressure switch that will allow the frame mounted inline boost pump to operate. If you hear the pump running a few seconds after shutdown, everything is ok with the switch. If you do not hear it, get a new oil pressure switch. (you will need a special socket to get it out. Get it at any NAPA store)

 

[Vaughn MacKenzie]

I saw one of those 6. 5TD jobs smoking really bad once. Loads of black smoke. The problem was due to the average-size trailer they were attempting to tow up a hill . We're talking approx 6-7% grade yet the trailer was enough to drag it down to 35-40mph. I can only image what his EGTs were being the hill was 6-7 miles long

 

[JoeyD]

Vaughn, You forgot to mention how many Dodge's he was pulling backwards to slow him down to that speed.