the3rsss
11-20-2006, 12:44 PM
I have an original 57 pontiac w a 347 engine. This engine smokes at start up and when idling, uses about a qt of oil every 300 miles. Easy right? Bad guides or valves...wrong! I pulled the heads, replaced the valves and guides, installed umbrella type seals had the heads fluxed and tanked. Removed and checked each piston and cyl for wear or out of round, nothing wrong still smokes. Good comp check 180-185 all cyls, good leak down test, good vac test. Cyl walls as well as pistons look new. If I take it up a hill at speed then let off the gas I get no smoke (rings). If I let it idle( high vac) then nail it I get smoke(valves). BUT THE VALVES ARE NEW!!any ideas??? Someone told me it could be a leaky oil passage INSIDE the head. HELP!!! PS: No vac modulator to the trans all mechanical.