carb pop
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carb pop
i thought I would throw this out here ,my 71 has started poping out thru carb when Iam between exceleratating and deexceleratating even when warm but not when cold and choke on a bit.its not bad just dont care for it.
I believe [but i do not know for certain] that popping out the carb is typically a lean condition. First thing to check is intake and exhaust leaks. Here are my notes ...
Intake And Exhaust Leaks Tests
You cannot get a good tuneup if there are intake leaks or exhaust leaks.
1. Check for Intake Leaks
With the engine idling spray propane gas or WD-40 around the carb/intake/cylinder head joints. WD-40 is said to work well because it has very fine spray droplets. Propane is best because it leaves no mess, and is most easily sucked in thru leaks. Be careful to not allow any of either to get sucked in thru the A/C as this will invalidate the results.
Any change in engine RPM is a leak which must be fixed.
EDIT: Experience is that this procedure will identify larger intake leaks, but it may miss very small leaks that also must be fixed. And that propane is definetly the better choice.
2. Check for Exhaust Leaks
Pour about 1/2 ounce of oil into each cylinder thru the spark plug holes. Run the engine at idle. You will get lots of smoke for about 5 minutes.
All smoke should come from the ends of the exhaust pipes/mufflers. Any other is a leak which must be fixed.
Intake And Exhaust Leaks Tests
You cannot get a good tuneup if there are intake leaks or exhaust leaks.
1. Check for Intake Leaks
With the engine idling spray propane gas or WD-40 around the carb/intake/cylinder head joints. WD-40 is said to work well because it has very fine spray droplets. Propane is best because it leaves no mess, and is most easily sucked in thru leaks. Be careful to not allow any of either to get sucked in thru the A/C as this will invalidate the results.
Any change in engine RPM is a leak which must be fixed.
EDIT: Experience is that this procedure will identify larger intake leaks, but it may miss very small leaks that also must be fixed. And that propane is definetly the better choice.
2. Check for Exhaust Leaks
Pour about 1/2 ounce of oil into each cylinder thru the spark plug holes. Run the engine at idle. You will get lots of smoke for about 5 minutes.
All smoke should come from the ends of the exhaust pipes/mufflers. Any other is a leak which must be fixed.
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