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1978 400. the truck has 134000 on it but i dont know if the engine is the original or been rebuilt or anything about it. all i know is that it puffs a little blue smoke on start up. any ideas?
black smoke = gas, engine running rich
blue smoke = oil burning ( bad thing : maybe bad seats, rings, or even cylinder walls)
white smoke = water burning
its sometimes dificult to determine wether its is black or blue smoke you are seeing
Smoke on startup is usually blue or black.
Blue means that you likely have some valve stem seals that are dried out and cracked. Go get some new ones, and invest in a valve spring compressor. They are very affordable now for the backyard mechanic. Good time to replace those valve cover gaskets that may be seeping by now too.
Oh, and in case it hasn't been done already; Welcome to FTE!
The 400 in my '79 has been puffing blue on startup for the last 10 years...it has been getting worse though. I'm with the others, it is probably the valve seals.
Wish I had done mine sooner. Found a piece of valve seal in my oil pump which locked it up and sheared a tooth off the cam(some idiot had put a nail through the distributer gear before I bought it). Good news is it gave me a reason to put a new motor in!
Do you have a spring compressor already?
I bought myself the kind that has two jaws top and two bottom and a handle to crank that compresses the spring. This works on a greater variety of engines, including foreign cars with overhead cam.