willyfastz

I'll try to make this short but with as much detail as possible. And if this is in the wrong section would one of the modds put it in the right place.

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.

willyfastz

No one has any idea's?

DaddySS

Smokes when? What color, what does it smell like, what other mods done, have you done a leak down test?

willyfastz

It's a 4.030 iron block with a Lunati 4" crank, Lunati pro rods, Diamond pistons, AFR 225 heads, Fast 90/90, 244/248 .612/.618 114 cam, and a Melling HV oil pump.

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.

flyin ryan

iTrader: (1)

If your sure its oil and not coolent, and your cylinders are round, I would be sure and check the valve seals and guides again.
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

vettenuts

iTrader: (4)

White sounds like coolant, or possibly condensation. Is it smoking once it gets how and is run as well? Try pulling a plug and checking for an exceptionally clean one, that is usually a sign that coolant is being burned.

willyfastz

It smokes no matter how far you drive it or how hot it gets. I don't fill that it's coolant, there wasn't any clean cylinders when I pulled it down and put this last set of rings in.

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.

MAC4264

This is the same old story with lots of 402's. If it were mine I would tear it down use all the same componets from the top end. Buy new pistons for the STOCK stroke crank and reuse the rods that are in your motor and use your 6.0 block. The motor will be 370 inches and you will not be dissappointed. When you go back for the tear down have your parts block and heads pressure tested for cracks and that will get any doubt about coolant burning gone. I think you have oil consuption in my opinion.