73f-250

I just rebuilt a 390 and it only smokes from the driver side after it runs for about 10 minutes. The smoke is a blue/white and when I step on the throttle the smoke pours out. any help or suggestions would help me out alot.

carnut73

sounds like a leaking head gasket(did you have the heads &block checked for flatness),or cracked head (white smoke is water burning) you can check the compression to varify leaking head gasket

73f-250

I had both the block and the heads all checked out by a shop and they said that every thing was all right. to day i will run a compression test to see if that is the case or not and let you know

73f-250

ok I just got done running a a compression test and all of the cylinders are same at 135 psi so the head gasket is all right most likely. could one the valve seals be bad?

tbird100636

Very possible, could also be an oil ring issue.

__________________
Master ASE Certified L1 Chrysler Technician- still a Ford fan at heart.
1964 Thunderbird Hardtop- Chantily Beige- 390 FE 4V V8-Uncle's Car
1966 Thunderbird Convertible- Red- 390 FE 4V V8- Uncle's other car- waiting for paint and body work!!!
1967 Mustang Convertible- Blue- 289 V8- helping a friend re-assemble this classic

73f-250

I took alot of time installing the pistons so im think a ring is not the problem. I guess I will pull the valve cover tomorrow and take a look.

73f-250

ok I pulled the valve cover and all of the valve stem seals looked ok but I still think that is the problem. The valve seals that I used are Positive stop Teflon from comp cams they are 3/8 valve stem and 0.530 in. Valve Guide Diameter and I dont know how they are supposed to be set up.

kdtrucker

did you get the head gasket on right. It looks like one is going on wrong but you need to make sure that the water can flow. The water comes through the block and up to the head at the long opening, then forward through the head and into the front of the intake and into the radiator. If you put the gaskets on exactly the same you are going to have problems. either way you look at it the head has to come off.

Did you do any porting of the heads?? If you grind too far and weaken the port it could spring a leak. Take the plugs out of the side thats smoking and crank the engine while someone watches and see what comes out.

FE Dude

Has it done this from the inital start up after rebuild or did it start smoking later. Did you re torque the intake manifold after the initial run in, if not it may have broken loose around one of the intake ports and could be pulling oil from the lifter valley.