Smoking Problem
Pulled a 408 stroker out that had two spun rod bearings. Had the crank turned, reconditioned the rods, had the heads serviced. Machine shop did a lite hone on the block to remove the glaze and vatted the block. Put it back together with file to fit ring gaped at .028 and .022. Motor ran great but smoked. Tried everything we could think of to try and get it to stop smoking. Ended up pulling the engine back out and getting a new set of Total Seal file to fit rings. Had the heads checked again to make sure it wasn't something with them. Put it back together and fired it up, runs great just as before but is still smoking. It also has a Melling HV oil pump that holds around 55lbs while going down the road and maintains around 45lbs when idling.
Any help and ideas would be gratefully appreciated.
Last edited by willyfastz; Dec 2, 2006 at 10:51 PM.
I haven't done a leak down due to just getting it back running late yesterday afternoon. It smokes all the time and is white in color. It doesn't really smell like burned oil but that could be becouse it's Rotella T 15-40. That's what the tech at Total Seal (brand of rings that were put back in it) said to use to help get the rings to seat.
One thing that worries me is that it has .005 piston to wall clearance and Diamond said they recomend .004. When looking at the pistons in the cylinders it looks like more but the machine shop mic'ed them and said they were all between 5 and 5 1/2 thousandths. I'm thinking that I may have to pull it back down and go with a 4.040 bore and get the piston to wall clearance back in spec.
My friend had a problem like this, rebuilt S/B and heads still smoked like a train .
Turned out to be valve seals.
He has over 7K on it now and no problems to date.
Good Luck i hope this helps
Ryan
What about this, When I pulled it down originally the ring gaps were at .017. I called Diamond and ask what they recommend for piston to wall clearance and they said .004. They said the .005 and .005 1/2 was on the lose side but was OK. The motor was supposed to be build for a big shot of nitrous but with a .017 ring gap it doesn't seem like it was really. I'm wondering if the original builder knew it was loose so they compensated the oil usage with the tight ring gaps. It now has .028 top and .022 second ring gaps which should be right for some spray, but now it smokes.
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