Question:
Bought a 1986 GMC 350
day 1 started up good - idle was rough - idle really too low, when brakes where applied, it would backfire.
(day 2) Changed oil which was really dark - oil filter too... ghanged spark plugs and wires. % 10 improvement... Engine lack power and vibrates but no more backfire.
day 4 Changed Cap and rotor - % 30 improvement -
day 5 Got the manifold gasket replaced. Same condition but silent...
day 6 Changed coil in cap ... Changed fuel filter % 60
improvement... The thing ran like new... Full power I started beliving again..Got full oil pressure 300 kpa - no valve noise
How much would it cost for auto labor?
Ran 30 minutes on highway. Valves started making noise especially on driver's side... Engine lost lots of power, and vibrates a lot... doesnt heat up to much but oil pressure seems very low.
I lost my car keys and dont have a spare!!!?
(day 7) Start up the thing, and even when cold and choke on, oil pressure not as good as in the beginning.
Please help car loosing ignition.?
What went wrong
Answers:
Sound like a blown intake valve. Do a compression test and if you find a bad cylinder, do a leakdown test. A leakdown test is where you pump compressed air into the cylinder with the bad compression. You need to make sure that both valves are closed which is determined by the crank position. If the air is leaking into the intake/carburetor, then you have a bad exhaust valve. Time to pull the heads, or do an engine swap.
As for the "buy a Ford" guy, the GM blocks are the best out there. That is why almost all marine engines are GM blocks.
vacuum leak, oil pump??
check those first
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loosing oil pressure like that,it sounds like the oil pump.if the parts arent getting oil,it will loose power.also check the timing,it could be off and loosing power.if the timing is off,it will make the valves noisy.What went wrong?
Bought a 1986 GMC 350.
Where can i go to do the inspected?
Solution?
(day 8) buy a Ford
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at first sounded like brake booster vacuum leak; the valve noise top end lack of oil ? if rod and crank bearings are good might be by pass spring on oil pump stuck or weak = low oil pressMore Questions & Answers ...
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