Mr. Jimmy

I looked at two 12 V's that are for sale today and noticed on both that when I cranked them up cold and held rpm's up around 1500, that they blew blue smoke and seemed to be misfiring or missing on one or two cylinders for a few minuites and then cleared up. Is this normal for trucks with around 100K miles on them? The first truck was a 95 5 speed ST X cab which had more rust than I care to fight. The second was a 4WD dually auto that seemed to run good w/ new tranny. Another concern on this one is that the oil level was very high, 3-4 qts high. Could it be that the injectors are filling the crankcase? Is there a way to test this quickly?

infidel

It's normal for any diesel engine to smoke and miss when it's cold.

On the overfilled one, you can usually smell the dipstick and tell if diesel is getting in the oil. If it was really 4 quarts high the oil would likely be whipped into a froth by the crankshaft after running for awhile, you could see it on the dipstick.

Perhaps it has the wrong dipstick?

Mr. Jimmy

I looked at the oil and it didn't seem to be diluted and no smell of diesel.After driving the 3500 and letting it sit for a few minutes I noticed a puddle of oil underneath the front side of rear differential which smelled like engine oil, not gear oil. The salesman said he thought it was coming from the blowby tube since the engine was overfull, although I could find no other trace of oil blown anywhere else underneath the front half of truck. The new tranny shifted really well and the motor seemed strong for a stock 12V. I can't believe how rough some of the 10 year old trucks are out there. Salesman is going to have the shop check out where the oil is coming from but will probably be mon before this happens.

Dshiftff

Mine blows blue smoke for the first mile or so I have 105K Have heard others with the same report, so Id say as long as it clears up in a resonable amount of time Id write it off.
I assume this is caused by inadequate amount of heat in the cylinders to burn the fuel all the way? anyone have any other speculation?

bmoeller

I think you are right on. Also, those trucks may need to have the timing bumped up a little.

P.O.R.

the oil leak might be from the KDP...check the timing cover for a crack

Mr. Jimmy

That's the first thing I always check for. I've killed 2 of them I did also notice that the valve covers were leaking enough to wet the exhaust manifold which I found sorta strange on a truck with 116K on it.

cumminsdriver635

Mine also misses/blows smoke when first started if you try to rev it. The new overflow valve, and bumped timing helped a lot. I suspect i still have a weak lift pump though.

Eric