I just experienced a very similar problem with my Prairie 300 a couple of months ago. I bought a carb rebuild kit off of ebay for ~$20 and it worked great. I couldn't see any damage to my float or valve either. If you already have the carbs off, i would just rebuild and clean them to be on the safe side. It sounds like you will need to order a new diaphragm from a local Kawasaki dealer. The large spring that pushes against the diaphragm had broke in two places on me, the dealer had me a new one in 5 days. Good luck.

By the way, the carb kit came with new jets, etc...

 

GR8,

Glad to hear a rebuild/clean fixed your similar problem. I was sure I was going to find a stuck float or some other obvious problem. I still have questions about the float level though. As soon as I figure out whether I can get that busted pilot jet out of the carb, I'll order the rebuild kit.

I'm kind of wondering if I can't get it out if I could get away with leaving it in there. The screw part of the jet is still enough in tact that it will screw in and I know the piece that is in there is not clogged. If I don't hear a "hell no, do not try that", I might just get the rebuild and give it a try. Worse case I'm out 20 bucks and some time.

Thanks for the reply.

 

jukeit,

Here are my suggestions to your questions:

1. Since my float valve appears to move properly and easily, could my float level be the culprit? When it was flooding real bad and I disconnected the fuel line, gas came out of the carb/fuel line connection for what seemed like a long time.

Don't get confused between "Fuel level" and "Float Height". You say flat level which is confusing. Incorrect "fuel level" would cause either too lean or rich running condition, not likely to cause real bad air box flooding problem. The page 2 of my fax shows the spec for the "float height (17 mm)" which determines the "fuel level" (0.5 +/- 1 mm).

2. My choke cable was not connected to anything in the carb; it just pulled out. The choke itself seems to seat ok when closed and opens ok when opened. Is this a problem?

No. The choke problem would cause hard starting problem when cold.

3. Could the other two problems (small tear in diaphram and broken pilot screw) cause the original problem. I may have been the one that broke the pilot screw (didn't use much force.)

Not likely but you MUST replace the diaphragm, but not the pilot screw since only the tip is broken off not the "jetting function" of the screw.

4. A rebuild kit is obviously the minimum here, but does it matter because I'm screwed with the broken jet and have to get an entire new carb anyway? Any suggestions on how to remove the broken tip?

You don't have to remove the broken off pilot screw. But if you want to, you may have to use a special tool like "ez-out" or just take it to a machine shop and an experienced machinist will do it for you in less than 10 muntes.

************************************************** **************'

Have you tried my first suggestion in my first response?

"Carb float valve not sealing and flooding the carb. Remove the float bowl and clean the float valve seat area."

Inspect the tip of the float valve and the seat area of the carb body. Becareful not to break the float valve rubber tip which could be very brittle by now. Get a wooden pencil (machine sharpened cone shaped tip) and rub/rotate into the valve seat area to clean.

 

When I was referring to level, I meant the float level....if the float's setting was too high before pushing the float valve closed, I could envision the fuel pouring out into the airbox.

I will check out the ez-out tool and machine-shop options for sure.

I did not clean the float valve seat yet, but thanks for reminding me. I will definitely do that as I'm rebuilding it. I never would have thought of a pencil for that job! I might be able to snag a used carb. If I can, then I will use the body of that one (since mine has a busted jet in there.) Hopefully the one I get will have an in tact diaphragm. I checked it out and those suckers are 106 bucks. Between the two carbs and a rebuild kit I think I should have one functional carb at the end of the day.

Any other suggestion on cleaning it out? I've seen the carb cleaner that comes in a spray form. Is that sufficient or is there a better type of cleaner? Any effective methods?

Thanks again for all the advice!

 

I have a street bike that I ride only 2~3 times a year, and the gummed up carb is an on going issue for me. Pulling out the carb every time I ride is not something that I want to do. I put fuel stabilizer into the gas tank (with full of gas) before putting away. Then, when I am about to ride, I pour in fuel additive something like STP or GUNK carb cleaner or fuel line cleaner or the Chevron Techron based Injector. Since I started doing this, I've never had to pull out the carb again from the bike.

 

I explained my problem to another person yesterday and here are his thoughts.....the cause of my problem is the small tear in the diaphragm. His theory is that the diaphram was able to provide enough suction to pull fuel up, but the tear prevented it from having enough pressue to stop the fuel once it started going. So it was like siphoning gas, once it was flowing it wouldn't stop. I thought this made sense and might explain why GR8 had the similar problem when his spring was broken.

 

The spring could have affected it, however, my diaphragm was not damaged. Also, I am not to sure that the diaphragm has contact with the fuel. In the least, you would need to replace that part any how. Give it a shot and see how it does. By the way, I dropped in a DynoJet kit when I rebuilt the carb. It was a good investment, I noticed a pretty good increase in mid to top range power. Good luck on finding a diaphragm replacement.

 

So I bought a new diaphragm and a rebuild kit, tore the carb apart, cleaned it (wasn't very dirty) and used compressed air to ensure nothing was clogged. I did have to adjust the float level. Whatever was causing the ORIGINAL problem has been resolved.

I had to make some idle and air/fuel mixture adjustments. It now starts right up and will stay running. Great right?

I somehow introduced a problem that wasn't there prior to the carb rebuild. I seem to have no power when engine is running at low rpms. If I'm on a slight incline, I have to Fred Flinstone the pig until I gather enough rpms for it to move itself. I can then shift through the gears and as long as my rpms are high enough....no problem. When my rpms are low....I have very little power.

The problem seems to be related to RPMs rather than throttle position. The one thing I know needs adjusted, but I haven't done it yet is my spark plug's gap is too small by approximately 0.2 mm. It should be 0.7 and is at around 0.4 or 0.5. The other thing I'm thinking is my air/fuel mixture is still off.

Any suggestions?

Thanks!

 

the dieaphram might have pulled the needle to far up and got snagged i went through alot to find this simple problem clean the seat and guid hole should help