If I'm gonna do all the work to replace the chain, I want to get other stuff out of the way as well. Sprockets, oil pan gasket, and water pump are pretty much a given. I'm planning on running kerosine or some other solvent through the engine before hand and then replacing the oil pump screen also. Anything else I should get while I'm at it? Is the oil pump worth replacing?

I don't think I'll be getting a new cam at this time due to the fact that I'm running the old stock heads with the old stock springs and I don't really have the time to be replacing them.

Also, roller cams rarely get worn correct? I ask because I'm replacing the chain due to a slightly rough idle and I want to be sure its not due to the cam but I would rather not have to remove the cam unless I need to.

 

also replace the woodruff keys in your crank. is your oil pressure ok? if it is you're just changing parts for the sake of parts, IMHO.

 

I will refer you to this post: https://www.thirdgen.org/forums/tech...ed-almost.html

Also, oil pressure drops significantly (as in down to 0) according to the gauge when the engine is warm and at idle. I attributed that to an old oil pressure sending unit, since it has been like this for over two months with no adverse affects (aka, blown engine).

 

your vacuum problem may be bad valve guides, given the exhaust smoke.