Kawasaki Motorcycle Forums banner

Carbs flooding Gas Pouring out etc.. Here is your fix

36446 Views 20 Replies 6 Participants Last post by  Kwakaman
I had a tough time tracking this problem down as you can see in this thread http://www.kawasakimotorcycle.org/forum/viewtopic.php?t=2365

But here is your fix

The flooding problem with gas pissing out of the carbs is caused by the float needles not seating properly, most likely from rust in the tank seeping into the float bowls and lodging up in there.

I would suggest to clean the tank, all fuel lines, fuel inlets on carb, fuel filter, petcock, float bowls, and the needles to solve this problem.

You can solve it by just cleaning the carbs but most likely it will come back very fast since there is still rust in the tank.

You should feel the want to clean the tank anyway if you have this problem since the rust will only stop up your fuel filter and rob you of power by causing your engine to run lean.

After that I would mix a small amount of oil in with the gas (follow standard 2 stroke premix directions for this, I know your motor is a 4 stroke) on your last run of the summer to help lube up the tank, this wont harm the motor or carbs but will mean you will need to change your plugs the following year which you should do anyway.

If you still skeptical here is some food for though, I have owned, drove, and raced rx7's for over 6 years and they inject oil directly into the motor to keep it lubed.
They do this constantly without you even knowing its happening, this is mainly because of the design of the engine but it just goes to show it wont harm anything.
Alot of people even opt to ditch the oil injection system all together in fear it might fail and not inject oil.
These people pour the oil right in their gas tank every single fill up and it harms nothing.

Also give MMO a shot (marvel mystery oil) try to make a habbit of using it as directed once every other month, or at least once a year.

If your bike is driven all year round I wouldnt worry about oiling it up too much since it would take a while for the tank to rust back up, but MMO is your freind. Make a habbit of using it once a year.

You can also try products such as seafoam, I once did a write up on seafoam aft (automatic trans fluid) and mmo (marvel mystery oil) and seafoam will clean the best if you want to knock some of the carbon deposits out of your motor, but MMO can be used in your fuel and oil or dumped directly into the motor and its tried and true on piston motors.

If this still doesnt do the trick or you are having other problems post here and I will do my best to help you out.

Please dont p.m. with questions because everyone wont see the individual fixes for each problem.
See less See more
1 - 6 of 21 Posts
Generally speaking floats dont just get thrown out of adjustment, I would try everything else first.

I have a carb guy who used to work for me and was teaching me about modding and rebuilding carbs and 1 thing I learned is dont mess with the floats.

first get everything working like the gas to stop leaking, then adjust the floats with a synchronizer to sync up the carbs.

If you havent played with your floats and they where working fine I would say they are still adjust correctly, or at least good enough to not leak fuel and get you running.

Try taking the floats out very carefully, remove the pins that hold them into place and set the floats aside in order so they go back in the carb they came out of.

After that very carefully remove the float valves one by one, they can go back in any order.

clean the float valves with a toothbrush some warm water and dish soap, get the tips good, make sure you dont fudge up the springs on the float valves though.

after that clean the carbs with warm water and dish soap, use a toothbrush to get inside the holes where the float valves set.

make sure you clean the entire bowl with a toothbrush and soapy water, also remove and clean the main jets with a toothbrush and soapy water, blow through each one to make sure they are free and clear.

after you have done all of this you can start the reassembly process and use some compressed air to blow out all the jets and where the float valves go.

Dry the bowl and all components good with compressed air or allow to air dry in doors over night, this will prevent any rusting, now lightly squirt wd-40 on some of the moving components in the float bowls, this will help keep the moving parts moving and help to prevent rusting.

Now turn the carbs aproximatly 45 degrees from being help upside down, with the floats all reattached and the floats just barely resting on the float valves NOT COMPRESSING THE VALVES you will notice the floats will sink down but not compress the little button on the float valves.

from there you can take a ruler and measure to see if each float is aproximatly 17mm from where the bowl seperates to the very bottom of the floats.

if your 16-18mm the carbs should not leak fuel.

After all this is done you should be in the clear.

Also if you noticed its every carb doing it and not just one or a pair then the chance your floats are off is even less likely, think about it, all 4 floats off and there all off in the same direction, and there all off enough to cause the carbs to leak fuel, highely unlikely.

But beware if you ask around (I noticed on this forum alot and other forums) people always try to get you to play with your floats, beaware of these people and just move on.

Only play with your floats for tunning, not to get the carbs to stop leaking fuel.
See less See more
Did you leave the vent tubes unplugged?
inbetween carbs 1&2 then inbetween 2&4 you should see some vacuum fittings, these are for the vent tubes and should be left unplugged, they may already have tubes on them, if you blow in them gas will come squirting out of the carbs
Project is not going to bad, I already ripped the bike back down, so far I have all the fairings to get painted, I have the oil flushed, coolant flushed ,head cover off (need to clean and set valve lash) gauges are all off ( making some custom ones). I still have to sync the carbs, do some painting touch up on the frame and motor, take off the wheels and paint them, install new brakes, and more :D

I am just taking it step by step, I also started sanding my header to get all the rust off then I will probably get it repowder coated or chrome plated, I also ruined my muffler trying to get it off the rusty pipe so I need a new muffler (sucks it was a yoshi) so I am going to buy one off ebay from any bike that looks like it has a straight pipe comming off the muffler then have my exhaust guy bend and cut it to spec.

Looks like its gonna be a while.

Glad to hear you got your bike back up and going, the bike was fun to ride while it was together, caint wait till its all done.
See less See more
Please do and reply with your findings, its really sounds like thats the problem.

Also remember that all 4 carbs are linked and it is highly unlikely just one will leak gas, usally the problem comes in 2's sometimes all 4.
1 - 6 of 21 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.