Fuel Leaking from Nikki Carburetor Bowl
#1
Member
Thread Starter
Fuel Leaking from Nikki Carburetor Bowl
Some background: Generac 4000 EXL portable generator with Generac engine and Nikki carburetor. I always drain all the fuel from the gas tank and remove the carb bowl, dump the fuel from it and reinstall. Recently I needed to use the generator so I added fuel and fired it up. It started and ran without a hitch. But when I brought the generator back into the garage I noticed it was leaking fuel.
I traced the leak to the top of the fuel bowl, by the O-ring seal. I know fuel is not supposed to be up that high so I took the carb bowl off. The float is plastic and does not have any fuel in it. With the bowl off I blew into the fuel inlet while I raised and lowered the float. I could blow easily when the float was low and couldn't blow when I raised the float. Neverthless, I took the float and float valve apart. No crud, the float valve moves easily.
I'm wondering if the rubber-tipped float valve has dried out and doesn't completely seal anymore. Fuel doesn't gush out around the bowl, it's a fairly slow leak. The unit has stood empty of fuel for the last three years. Can I soak the rubber-tipped valve in something to soften/restore it? I hate to buy a rebuilt kit just for the float valve. Or is there something else I should pursue?
Thanks.
I traced the leak to the top of the fuel bowl, by the O-ring seal. I know fuel is not supposed to be up that high so I took the carb bowl off. The float is plastic and does not have any fuel in it. With the bowl off I blew into the fuel inlet while I raised and lowered the float. I could blow easily when the float was low and couldn't blow when I raised the float. Neverthless, I took the float and float valve apart. No crud, the float valve moves easily.
I'm wondering if the rubber-tipped float valve has dried out and doesn't completely seal anymore. Fuel doesn't gush out around the bowl, it's a fairly slow leak. The unit has stood empty of fuel for the last three years. Can I soak the rubber-tipped valve in something to soften/restore it? I hate to buy a rebuilt kit just for the float valve. Or is there something else I should pursue?
Thanks.
#3
Member
Thread Starter
Any suggestions for cleaning the rubber-tipped float valve? I believe I have some automotive aerosol throttle body cleaner that is supposed to be safe for rubber. The seat is brass and looks fine but I'll take a closer look with a brighter light and magnifying glass. Is it not wise to leave the fuel bowl empty for long periods of time (years)?
#4
Yes, it's best to leave it dry if you will be letting it sit for more than a few months. If you hadn't, you might be looking for a new carb now rather than just fixing a leak. Use regular carburetor cleaner in the spray can and a q-tip to clean the needle tip and down in the seat area. I like next-dimension brand carb cleaner from advance auto parts best.