In general, blue exhaust smoke means that you're burning oil. Black or grey smoke means that you've got unburned fuel. The dreaded white smoke means that you're burning coolant. I was wondering what a puff of blue means when you let off a heavy throttle. I ***ume that vacuum is pulling oil from somewhere. Is it from the valves, valve guides, or piston rings? If it shows only after lifting off the accellerator, does that help narrow it down? Does anyone else have some helpful tech tips on how to read any signs of smoke coming from tailpipes?
You nailed it...vacuum is ****ing oil from somewhere....usually it's from hardened valve guide seals. Sometimes replacing the seals will cure the problem and sometimes the guides are leaking too much oil for even new seals to control. If you gotta sbc, replace the o-ring style seals with mid 60's 289 ford umbrella seals for better oil control..
PS, the ford seals are cheap and you can replace the seals with the heads still on the engine with the aid of compressed air to hold the valve shut while you change 'em..
[ QUOTE ] The dreaded white smoke means that you're burning coolant. [/ QUOTE ] White smoke could also be something as simple as a ruptured vacuum modulator on an automatic transmission that has one like a T350 or T400.
A good indicator of leaking valve seals is after you've warmed the engine,shut it off and let it set for a bit,when started will usually give off a puff of blue smoke.
I have used small rope, pushed it through the spark plug hole. Turn it over by hand till it gets tight.Didnt have a compressor.---Feder
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