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Discussion Starter · #1 ·
Hello All,

have carburetors clean and rebiulted, at least, to the fuel pump.In the fuel pump cover there are to holes,

one is for fuel to come into the pump from the float bowl, and the other hole is to allow fuel to go to the carburetor

air stream. this hole in the pump cover is plugged up, looks like from the factory. nothing gets out of the pump cover.

Has anybody got a idea why. All help appreatiated. ( that word is spelled wrong).

Thanks, OLDBIE
 

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I believe you are referring to the accelerator pump. This shoots a small amount of raw fuel into the venturi when the throttle is snapped open. It is to give the engine a little burst of fuel until the carbs can respond to the need for more fuel. I think they were first used about 1980-81.



It should be possible to check their operation by manually operating the push rod and see if fuel is burbled out the check valve by the tiny O ring. The check valves are a tiny square of brass centered in a round hole over a ball and spring. It is possible that they can become gummed up, and the valves don't operate properly. If you pry the brass square out to clean, don't lose the parts.
 

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Discussion Starter · #3 ·
Thanks, Blue fox,

These carburetors where clean when I torn them down, not that this check devise would not be stop up.

I have applied vacumm and pressure to the cover and got no results. The little square bras plug looks

like it might be a bogabear to get out. The second hole in the cover looks like it has brass or plastic

plug in it. Thanks, OLDBIE
 

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Oldbie,

The check ball gets stuck in place as old fuel dries up in there. One of the ways I have been able to loosen them up is to use carb spray to soak the inside of it for quit a while. You can place the pump cover upside down in the plastic cap that comes on the carb spray. Fill the cover up with spray and also squirt it into the hole that goes down under the check ball. You'll have to keep adding carb cleaner to it occasionally because it dries out pretty fast.



The only other way I have fixed them is to drill a hole in the bottom of the cover and push the brass plug out with a thin piece of rod. After the seat and ball assembly is cleaned, I have to TIG weld the hole to seal it up again before I put it back together.



Is the check ball in the bowl stuck too.



Larry
 

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Discussion Starter · #5 ·
Hello,

Another question on these carburators. I have the carbs. separated. When hooking them back together how does the left hand carb.choke

shaft hook to the right carb. I wish was a picture or thread.

Thanks( not smart as I thought I was) OLDBIE
 

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Discussion Starter · #6 ·
Oldbie,

The check ball gets stuck in place as old fuel dries up in there. One of the ways I have been able to loosen them up is to use carb spray to soak the inside of it for quit a while. You can place the pump cover upside down in the plastic cap that comes on the carb spray. Fill the cover up with spray and also squirt it into the hole that goes down under the check ball. You'll have to keep adding carb cleaner to it occasionally because it dries out pretty fast.



The only other way I have fixed them is to drill a hole in the bottom of the cover and push the brass plug out with a thin piece of rod. After the seat and ball assembly is cleaned, I have to TIG weld the hole to seal it up again before I put it back together.



Is the check ball in the bowl stuck too.



Larry
 

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I would try to soak it for at least an hour first. It usually works.
 

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I cleaned my carbs, including ultrsonic, and reassembled. Had a hesitation. Pulled the left bowl, actually to grind off the idle mixture screw tab, and put water in it. Opperated the rod and nothing squirted out. I had to take a piece of wire to the holes associated with the pump and pulled out a lot of gooey stuff. Back into the ultrasonic and when I tried water again it worked great. As many have said on this forum, just because you clean them does not mean that they are clean.
 

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I cleaned my carbs, including ultrsonic, and reassembled. Had a hesitation. Pulled the left bowl, actually to grind off the idle mixture screw tab, and put water in it. Opperated the rod and nothing squirted out. I had to take a piece of wire to the holes associated with the pump and pulled out a lot of gooey stuff. Back into the ultrasonic and when I tried water again it worked great. As many have said on this forum, just because you clean them does not mean that they are clean.


The problems and frustration you have encountered many of us have been through especially with Carbs.In many cases we are fighting years of neglect.The good news is when well serviced and kept that way you may have no problems with them for years in regular use.

In one case I didn't touch the carbs on one of my CX for over 3 years regular use and then only because the bike got lent over and dropped crossing a ruddy stream/ford




http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=11&t=307





Which also later I found crapped out my battery




Tip:when you can replace the Phillips screws in the float bowls for small Allen screws/bolts(Or at least the hard to get to inner one).Then you can do a quick in-bike float bowl clean from time to time.Even with an in-line fuel filter(You should fit one if you don't want to undo your good work) some crud get through or sediment in there just waiting to grit up the Float needle valves.
 
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