how to tell when carb is bad
#23
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Location: Temecula Valley, CA
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there is no easy way to test the fuel pump for leakage except to pressurize the ports with no more than 10 psi and listen for air hissing at the lever end.
and fuel leaking from the carb, down the intake and into a cylinder can and will get around the rings since the rings do not completely seal the cylinder due to having end gaps
and fuel leaking from the carb, down the intake and into a cylinder can and will get around the rings since the rings do not completely seal the cylinder due to having end gaps
#24
Registered User
The number one cause of fuel in the oil on a carb engine is the mechanical fuel pump.
However it is possible that an air bleed in the carb is clogged and allowing the fuel to be siphoned from the float bowl after the engine is shut off. Usually when this happens the engine will run very rough at idle but smooth out when driving down the road. The float bowl doesn't hold very much fuel but after many run cycles you'd be suprised to find how much fuel can end up in the oil.
However it is possible that an air bleed in the carb is clogged and allowing the fuel to be siphoned from the float bowl after the engine is shut off. Usually when this happens the engine will run very rough at idle but smooth out when driving down the road. The float bowl doesn't hold very much fuel but after many run cycles you'd be suprised to find how much fuel can end up in the oil.
#25
Registered User
Thread Starter
thanks for the info.
i was shocked when i saw how much did come out, brought my mental state to the same point when my headbolts broke on my 325ic..i am soooo happy this truck actually started after a simple oil change (and forced internal engine cleaning)
now i have to find
1. rebuilt carb (any you guys suggest)
2. cheap fuel pump (again, any suggestions)
3. pvc valve ??
4. charcoal can ??
there is no easy way to test the fuel pump for leakage except to pressurize the ports with no more than 10 psi and listen for air hissing at the lever end.
thats what i heard when it was parked (keys in pocket -off) from the carb.
and fuel leaking from the carb, down the intake and into a cylinder can and will get around the rings since the rings do not completely seal the cylinder due to having end gaps
thats what i heard when it was parked (keys in pocket -off) from the carb.
and fuel leaking from the carb, down the intake and into a cylinder can and will get around the rings since the rings do not completely seal the cylinder due to having end gaps
1. rebuilt carb (any you guys suggest)
2. cheap fuel pump (again, any suggestions)
3. pvc valve ??
4. charcoal can ??
#27
Registered User
Thread Starter
yeah, i could add that its also robbing me of fuel and time...
btw.
now i have to find
1. rebuilt carb (any you guys suggest)
2. cheap fuel pump (again, any suggestions)
3. pvc valve ??
4. charcoal can ??
btw.
now i have to find
1. rebuilt carb (any you guys suggest)
2. cheap fuel pump (again, any suggestions)
3. pvc valve ??
4. charcoal can ??
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