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post #1 of (permalink) Old 08-07-2004, 12:03 PM Thread Starter
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carb/fuel question

hi there

my 258 is reluctant to start after a 2 year break

i've got the top of my carb off in my 82 cj7...

i'm watching fuel go into the bowl...it seems to pulse into the bowl as i turn the engine over rather than flow (the bowl is empty of fuel).

should the fuel flow rather than pulse?

what would be possible solutions to this problem if it is a problem?

i'm not up on my carb terminology so a not so bright persons explaination would be appreciated!!

thanks
patrick
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post #2 of (permalink) Old 08-07-2004, 01:21 PM
 
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Re: carb/fuel question

While you are cranking it over, the motor is spinning at a very low rpm compared to running. The mechanical pump works by a cam pushing a lever. Because its on the camshaft, it spins at half the engine speed. Each push of the cam on the lever depresses the diaphragm in the pump and squirts gas. That's what you are seeing, and as long as it pump decently at cranking speed, the pulses of fuel are to be expected.

After the motor sits for a while, you can see if the float bowl is dry (not sure how that would occur) by looking down the venturi and moving the throttle linkage. If there is no fuel, the accellerator pump won't work. Try that next time it wont start to see if the bowl is dry.

After a two year break, the old fuel would be stale and not burn well. Also, the fuel that evorated would have left sludge in the system and it could be plugging the idle circuits. Consider cleaning and rebuilding the carb.
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post #3 of (permalink) Old 08-07-2004, 06:21 PM Thread Starter
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Re: carb/fuel question

thanks

on another note...

i see gas squirt down the venturi when i pump the accelorator...but nothing is dripping down when i don't pump the acc.

what happens when the engine starts running that supplies enough fuel to keep the engine running?

thanks
patrick
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post #4 of (permalink) Old 08-07-2004, 08:23 PM
 
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Re: carb/fuel question

Those squirters are for the accellerator pump only. The fuel for running comes from a different circuit.
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