Hey all, new here;

Short of it: have had the fat cat since new, haven't used it in 13 years. I spent the weekend cleaning up the carb and trying to bring it back to life. I have a few issues that I've run into:

1. The gas tank had fuel in it and it's rusted on the inside. I've washed it out and poured out the chunks of rust particles until it was cleared.
2. The fuel valve doesn't really work, it always allows gas flow (have ordered a new one)

The carb itself was pretty gummed up (as expected). I cleaned everything up as best I could, the jets looked spotless and you could blow air through them. There was one port on the air intake side that I wasn't sure about. It sits just under the intake manifold and looks like it heads into the pilot jet. The mix port runs perpendicular to it just under it (that one is clean all the way through). I couldn't get a pin through the afore mentioned port, but don't know if you're supposed to (it may angle away).

I can get it to start with full choke. I put the choke down to half choke and it will idle (a little rough, but not bad). I can't get it to run with the choke down without throteling up. I road it around the yard riding the choke up and down (with throtle open, choke down, or throtle closed choke at half). I've tried adjusting the mix on it, but I can't find the sweet spot to make it run right.

Any suggestions? Could it be an air leak, or just a gummed up port or bad gasket/rubber washer from cleaning too hard?

 

If it's only running with choke that's a sign that it's still clogged up. Get a gallon of chemdip from Autozone or somewhere take the carb. apart and let it soak overnight, blow the passages with air and wire the jets, especially the pilot. P.S. if it has an air leak it will be idling way high.

 

Thanks for the suggestions...I have a gasket kit on order, so when I take it off for that I will soak it again.

 

Blasting it out with a spray can of chemtool b12 after the soak might get it.

Regarding the fuel valve, you may be able to take it apart and clean it. Likely has rust chunks in it.

You are going to have to do something more than just flushing out the tank, or its just going to plug up passages again.

 

Are you thinking I should replace the tank, or just add a fuel filter to the fuel line or something else?

I'm new to this, obviously, so there is probably a lot of things I should be doing to bring this back to performance shape.

 

There are some kits with chemicals to remove rust, and to put a coating in the tank. Some have had luck with them, but if your tank is pretty rusty you might see if a replacement plastic tank is available at a reasonable price.

If you do reuse the tank, the in-line filter thing is a good idea.

Sounds like a fun project.

 

Remember to "blow" in the reverse direction that the fuel and/or air flows so that you can blow out what ever is causing the restriction and so that you don't push it futher into the pasage.

My wife's mother has a Fat Cat with only 800 miles on it, still looks like new.

 

I would like to say thanks to every one for their help!

I bought a gallon of chem dip, a gasket kit, a fuel valve, a fuel filter and some new jets. I stripped the carb down and soaked the parts over night. Assembled everything with the new parts and gaskets and it fired right up. I also should add, that I cleaned out the gas tank as best I could with some gas. It wasn't rust after all, but varnish (is that word for dried gas?). It's running great now, so thanks for all of the tips!

 

Glad to hear you got it going.

Have fun with it, carefully.

 

i have the same engine in my 200sx, great engine and the fat cat is already a collectors bike! I have a yamaha bw200 and looking for a fat cat!