1980 kawasaki kz750 leaking gas??

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billsin_09

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At the bottom of the carbs theres four points or valves. When sitteing on the bike the one to the right leaks gas out of it when running and i cant figure out why...can u please help, also when on res tank it doesnt happen.
 
Its most likely a sticking needle or bad float. Carbs have vents that will drain gas when the needle doesn't seat. Pull the carbs off and remove the float bowl, you can get rebuild kits for them at the dealer or maybe Dennis Kirk. Make sure they are the stock carbs though so you don't get the wrong kit.
 
Does your bike have a vacuum operated fuel petcock? Starting in '79, the 1000's did. If so, the lever will have three positions, main, reserve and prime. If not, instead of prime it'll say off.

You don't say which carb leaks gas, but if you have a vacuum operated petcock, it's probably the diaphram and/or rubber gasket inside the petcock that's leaking. The vacuum line for the petcock comes from one of the inside carbs and if the petcock is leaking, the gas runs through the vacuum line and directly into the carb.

If it's the float valve in the carb, it wouldn't make any difference what position the petcock is in. If it's the petcock, that would explain why it doesn't leak on reserve.

I don't think Kawasaki sells the petcock repair kits anymore, but your dealer should be able to get one aftermarket. I've also seen them on ebay. Just make sure you get the correct one for your particular model of bike because different models, even of the same engine displacement used petcocks with different petcock lever configurations. The repair will probably be around $30-$35 and is easy to replace. Just be sure to initially smear a bit of oil on the flat side of the petcock where it contacts the rubber gasket so you don't tear the gasket the first time you turn it while still dry.
 
Shut the fuel off at the petcock, then try to remove the 4 screws holding that leaking carbs float bowl on. Have rags and a can nearby to catch the gas that will come out when the bowl is removed. Next pull out the rod that is holding the float in place and remove the float assembly. I am betting that with the age of the bike being 1980 that the float needle valve needs replacing. So just get one and install it. Hook everything back up and wallah, done.
 
You don't need to replace anything. Turn off the fuel tap. empty the offending float chamber by undoing the large slot head screw about two turns. blow down the fuel feed pipe to dislodge what is fouling the float needle. This'll do it 9 times out of 10.
Before refitting the fuel pipe fit an in-line fuel filter (only 3 or 4 pounds) to it to prevent dirt from re-entering the carbs.
If this doesn't work, undo the four cross head screws holding the bowl to the carb body then remove and clean the float needle and blow out the valve. This is fiddly, but not as fiddly as replacing carbs and air filter.

Another of your advisors has sugested smearing oil on the petrol tap gasket. Don't use oil !!! use petroleum gel (vasalene). The oil will react with the petrol and dry and crack the gasket. The vasalene is inert, so will not react. It is a good idea to do this though.
 
You don't need to replace anything. Turn off the fuel tap. empty the offending float chamber by undoing the large slot head screw about two turns. blow down the fuel feed pipe to dislodge what is fouling the float needle. This'll do it 9 times out of 10.
Before refitting the fuel pipe fit an in-line fuel filter (only 3 or 4 pounds) to it to prevent dirt from re-entering the carbs.
If this doesn't work, undo the four cross head screws holding the bowl to the carb body then remove and clean the float needle and blow out the valve. This is fiddly, but not as fiddly as replacing carbs and air filter.

Another of your advisors has sugested smearing oil on the petrol tap gasket. Don't use oil !!! use petroleum gel (vasalene). The oil will react with the petrol and dry and crack the gasket. The vasalene is inert, so will not react. It is a good idea to do this though.
 
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