New Engine Smoking!

[mstockton]

Hi, installed the rebuilt mill into the '82 blazer yesterday, and man it smokes ALOT when its cold, i could wipe out 3 lanes of traffic with how much it smokes, all white, a little bit of blue too. Once she warms up, smoke goes away, i have new ac60g gp's, new batteries, but an old glow controller, new 6.5 heads, stock intake, and a disconnected cdr system, no egr, no vacuum connections whatsoever. I'm thinking it may be the glow controller, and i know my cold advance switch was corroded, but i could not get a new one in time, so i'm wondering if its stuck so the advance is not working. The timing on the IP i set by ear, so be the smoothest idle i could get. I'm wondering with only 140 miles on the rebuild, if part of it is the new rings not seated yet. Oh also have rebuilt nozzles, rebuilt IP, etc.

[Robyn]

Glow system is totally out of the picture by the time you clear the driveway.
The cold advance could be an issue though.
The engine should have a fairly agressive rattle while the CCA is on.
Also the fast idle is also activated at the same time.
Check your CCA plug on the IP (rear most plug) to see if you have 12V
If you do have 12V try running the engine and unplugging the advance, you should notice quite a difference in the running.
If there is no difference the advance is not working.

Robyn

[Slim shady]

Can you give some info on the motor; 6.2 low compression motor, stock motor or some other helpful information.

My new motor smoked like crazy before the rings fully seated. It took me about 3000 miles before it didn't smoke so bad. I could make my neighbors vanish in a cloud of white smoke it was that bad.

If you have a manual pump the cold start (cold start switch on the head) shuts off electricity to the fuel return selonoid on top of the injector pump housing and raises the internal fuel pressure of the injector pump. This advances timming in the manual pumps (cold start timming advance). At least that is what they taught us at the GM Tech Center when I learned to rebuild them for the Chevy dealer. It was great money then as it is now.

Slim

[Slim shady]

I was editing my reply as you posted yours. Hope we agree, I beleive it is his cold advance not working or he has his base timming set to low. Both make cold starts very hard in cold weather.

Slim

[john8662]

I didn't have much smoke other than a very little amount of black smoke on my first start, then a slight white smoke (typical of any diesel) when I fired the '86 for the first time.

I suspect timing being off somewhere (too far retarded), possible IP gear off one tooth.

How much rattle do you have, does it sound pretty quiet when you accelerate or more of a "powerstroke" noise?

You could also have a case of bad fuel, as the case with something that had been sitting while you're reabuilding...

J

[mstockton]

Well here's an update, it only got down to 30 F or so last night, but I had it plugged in all night anyways, went out and started it at 45 F, and the smoke was much better, a little cloud that quickly dispersed after about 20 seconds. I also did find that my cold advance was not working. The switch wasn't flowing the juice, went to GM, the parts guy and I couldn't find the switch in all their schematics, so I went home and wired up the advance and fast idle solenoid to a toggle in the cab, and used to male spades to connect to the orginal pigtail for the switch, so I wouldn't have to hack my wiring harness. Now it starts even easier. We shall have to see how its doing tommorow morning. Its only going to get down to 34 F tonight, so I think will leave her unplugged tommorow for a test. The engine now has about 220 miles on it as of today. As far as my timing adjustment, I started at random of sorts, my old pump and timing housing had been marked with a zero, and my new pump was simply a hash mark, so i placed the hash mark between the zero lines on the housing. Then once it was running, I adjusted the timing by turning the pump to the drivers side till the idle picked up a bit. It rattles a bit, but the rattle seemed to calm down once I adjusted the timing. Should I adjust it back the other way, or stick with what I got? The rebuild is running amazingly well once it gets warmed up, but I have no black smoke no matter what throttle position/gear i'm in. The bottom end is a stock original '82 6.2, with late 90's 6.5 heads on it. I've got stock rebuilt 6.2 nozzles and a rebuilt light duty '90 6.2 IP.

Thanks for the input,
Martin

[Slim shady]

I can't tell you that you can set the IP timing without a tool. YOU can set it so that it runs well and won't damage your motor when it gets warm.

Manual pumps must have the idle screw backed off until the motor just stays running. Then back off the timing until it just starts and stays running with a little rattle (like a coffee can with a few marbles and a rag in it). This will get you someplace real close to a start point.

Then play a little at a time with advancing the injector time (rotate towards the driver side) until at a set idle it just rattles like I said above.

I know this is not OFFICIAL but that is how we used to do it in the dealer and then we would check it with an "optic timer" and it usually was within a degree or two of the factory spec.