1990 kaw zx7 750H2 overflowing carbs
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1990 kaw zx7 750H2 overflowing carbs
I have a 1990 zx7 that I have recently jetted thecarbs because when I got it, it had a high flow exhaust system. I have rebuilt the carbs before I jetted it and the carbs are overflowing. What can make thecarbs overflow? I have adjusted the floats in the carbs to make sure that they weren't filling up, but still overflows. I also didn't have a petcock, just hose straight from tank to fuel filter. I have since bought a used petcock, but it flows gas on res,on, and off. Could the petcock be the prob? I need help please, not much riding time left!!
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RE: 1990 kaw zx7 750H2 overflowing carbs
The petcock isfaulty if gas is able to flow through it no matter what selection it is set at.
Now, because your carbs are also overflowing even after the floatswere set. (provided they were correctly set) Either the seats or heads of the float needles could be shot, or, the more likely scenario is you have rust particles collecting all over in your fuel system froma rustytank. When rust particles collect on your seating surfaces (like where your needles seat), it will allow fuel to bypass through your needles, allowing gas to overflow. The same thing could be happening at your petcock diaphragm, not allowing the diaphragm to seal shut.
Now, because your carbs are also overflowing even after the floatswere set. (provided they were correctly set) Either the seats or heads of the float needles could be shot, or, the more likely scenario is you have rust particles collecting all over in your fuel system froma rustytank. When rust particles collect on your seating surfaces (like where your needles seat), it will allow fuel to bypass through your needles, allowing gas to overflow. The same thing could be happening at your petcock diaphragm, not allowing the diaphragm to seal shut.
RE: 1990 kaw zx7 750H2 overflowing carbs
ORIGINAL: markmeinteil
The petcock isfaulty if gas is able to flow through it no matter what selection it is set at.
Now, because your carbs are also overflowing even after the floatswere set. (provided they were correctly set) Either the seats or heads of the float needles could be shot, or, the more likely scenario is you have rust particles collecting all over in your fuel system froma rustytank. When rust particles collect on your seating surfaces (like where your needles seat), it will allow fuel to bypass through your needles, allowing gas to overflow. The same thing could be happening at your petcock diaphragm, not allowing the diaphragm to seal shut.
The petcock isfaulty if gas is able to flow through it no matter what selection it is set at.
Now, because your carbs are also overflowing even after the floatswere set. (provided they were correctly set) Either the seats or heads of the float needles could be shot, or, the more likely scenario is you have rust particles collecting all over in your fuel system froma rustytank. When rust particles collect on your seating surfaces (like where your needles seat), it will allow fuel to bypass through your needles, allowing gas to overflow. The same thing could be happening at your petcock diaphragm, not allowing the diaphragm to seal shut.
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RE: 1990 kaw zx7 750H2 overflowing carbs
I would suggest before buying sealer for your tank,remove the carb bowls so your floats are exposed. (fix or replace your petcock valve first so you can control your fuel flow before taking off your bowls.) Next, hold the floats up with your fingers so the needles are seated, and then allow gas to flow into your carbs. Let one float down at a time (Then push it back up again.) to see whether or not gas is bypassing the needles. Also check for any dark particles of rust.
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RE: 1990 kaw zx7 750H2 overflowing carbs
ORIGINAL: madhatter314
Wont that make kinda of a mess? Is there something other than gas I can use? That stuff is like liquid gold these days.
Wont that make kinda of a mess? Is there something other than gas I can use? That stuff is like liquid gold these days.
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RE: 1990 kaw zx7 750H2 overflowing carbs
You need to find a way to shut off that fuel. Repair/replace the petcock, first. That should fix the overflow to the carbs, which causes your floats to malfunction. Drain the bowls and refill with a functioning petcock. Make sure to turn off the fuel flow/petcock when the bike isn't running. You may not need to actually pull the carbs to fix your float problem, if you've already made certain they're mechanically sound.
If you're getting fuel overflow in your carbs, it's very likely you've also contaminated your oil (due to the overflow into the cylinders. (I've seen this happen before.) Just to be sure, double check your oil before you do any damage.
If you're getting fuel overflow in your carbs, it's very likely you've also contaminated your oil (due to the overflow into the cylinders. (I've seen this happen before.) Just to be sure, double check your oil before you do any damage.