<VV> Heater Smoke

[Smitty Smith]

Smitty Says:   Ray, you are right to be concerned about the source of your smoke.  Normally though exhaust is not smokey and is even less so after the engine warms up.  Let's talk about exhaust leaks first.  Usually the leaks that get into the heater system are either exhaust "stacks" or head gaskets.  To check for stack leaks, put the car up on solid jack stands.  Remove the fan belt and the manifold cover pans.  (remove fan belt so the rushing cooling air coming down from the fan won't confuse the issue).  Start the engine cold and quickly get under and start feeling for gasket or tube leaks.  Things get hot pretty quickly.  If you find a questionable place, jazz the throttle by use of the linkage down there to make a leak more noticable.
  Concerning the head gaskets, a leak there is almost always marked by a black gummy deposit on the bottom at the joint between the cyl barrel and the head.  Also leaking head gaskets are quite often identified by a chirping from the engine when it first lights off.
  Getting back to the smoke, while you have the car up and the manifold covers off, check the pushrod tube ends.  They should be dry.  No oily film on them at all.  Check for oil coming down from above on the block. (upper block cover).  If those areas are dry then you may have smoke from oil elsewhere but it won't be getting into the heater except by secondary means of being re-ingested by the cooling fan.