slantsixdan
=..=
One point twenty-one, of course! :-D
Fuel/Oil spewing out of breather valve on valve cover.
- Thread starter TNAILAV
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One point twenty-one, of course! :-D
ChazRam
1964 Valiant V200
Just a question from a fellow slanter in the backround. Exactly why did you change out the fuel pump in the first place? Not trying to be a smarta$$ but it was stated that the previous owner thought it was repaced recently. Was there some issue in starting, running or something of the like going on? You hit the right place to find out and Slansixdan is one of the 'guru's on these motors. The guy has more knowledge on them than alot of people. Ask away, he will tell it like it is. alot of others here also will be much help too as we all like the slants and this is a very informative forum!!
Chas.
Chas.
Kevin Johnson
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Check your emission controls for the proper fuel tank venting (or lack of venting). In an older car it is possible these have been modified at some point (plugged off -- who knows).
If the fuel tank has no venting the vapor pressure in the tank will try to push gas through the lines like a gentle aerosol can. I looked at some diagrams of fuel pumps and it is not immediately obvious whether -- at rest -- they would stop a gentle steady flow of gas through the inlet and outlet valves -- and this may depend where the pump lever came to rest on the cam eccentric lobe.
Simply said, this might mean the fuel pump is not defective but is allowing fuel to go to the carb under a slight steady pressure. Owners of older motorcycles with gravity fed carbs will be familiar with how carb float valve seats will leak and allow the carb to drain fuel down the inlet manifold, through open valves onto pistons, past the rings and into the crankcase. This is why you close the petcock(s) on the tank if the bike is to sit for any length of time.
You mentioned you were installing clamps on the fuel line. Just a wild *** guess but might this have been made neccessary by the effects of a slightly pressurized line developing leaks versus a line that is normally "sucked upon" by the pump? Jacking up the rear of the car to change the tire might be related to it as well -- increases the head pressure from the tank relative to the carb float valve -- though I certainly don't think your crankcase would fill up in minutes with gas.
Good luck.
If the fuel tank has no venting the vapor pressure in the tank will try to push gas through the lines like a gentle aerosol can. I looked at some diagrams of fuel pumps and it is not immediately obvious whether -- at rest -- they would stop a gentle steady flow of gas through the inlet and outlet valves -- and this may depend where the pump lever came to rest on the cam eccentric lobe.
Simply said, this might mean the fuel pump is not defective but is allowing fuel to go to the carb under a slight steady pressure. Owners of older motorcycles with gravity fed carbs will be familiar with how carb float valve seats will leak and allow the carb to drain fuel down the inlet manifold, through open valves onto pistons, past the rings and into the crankcase. This is why you close the petcock(s) on the tank if the bike is to sit for any length of time.
You mentioned you were installing clamps on the fuel line. Just a wild *** guess but might this have been made neccessary by the effects of a slightly pressurized line developing leaks versus a line that is normally "sucked upon" by the pump? Jacking up the rear of the car to change the tire might be related to it as well -- increases the head pressure from the tank relative to the carb float valve -- though I certainly don't think your crankcase would fill up in minutes with gas.
Good luck.
TNAILAV
TNAILAV- VALIANT
I did not know he had changed it before I put a new one in.
Kevin Johnson
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Well, one reason is that if the circuitry failed they would be sued up the ying yang.
Think unexplained failure of multiple blowout protections on exploding oil rigs.
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