1989 B2200,very heavy white smoke coming from exhaust shortly after start-up, becomes much less after 5 minutes,it is antifreeze, replaced head gasket & related gaskets.head warpage is only 2 thou. could not visually find any cracks in head or block. how do I find out how antifreeze is getting into combustion chambers.It appears antifreeze goes into intake manifold and is meant to be near base of carberator. My manual shows this but is not very explicit. Can antifreeze get into the intake from some of the polution devices? help.

I've the exact same problem with my 89 b2200. white smoke in the morning for about a minute, then its gone, and is usually gone for the rest of the day. I changed the head gasket, no help. Put on a new head, still same problem. I suppose the intake manifold could be cracked, but i doubt it. I haven't been able to find the problem, the haynes book doesn't really show much on the carb.

the smoke is not coolant it is engine oil . the piston rings are the problem repaired many myself.

I agree with mech. When I baught my truck it had the same problem. The exsaust would be white for about 10 min and then would be fine, it would also do it after a good rev. I put new rings in it and it was fine. The F2 block has a high nickle content which makes the block extremly durable but also causes it to eat rings if not properly maintained. I put moly rings in mine so I wouldn't have any further problems.

I agree a ring problem. I just changed mine and they were all but gone when I disassembled the engine. You can do this job with the motor still in the truck and took me about 2.5 days to complete. Now running fine and no more white smoke.

its the valve seats in the motor.