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Discussion Starter · #1 ·
Got a 05 prairie 360. Sat for a while just rebuilt the carb. New gas. It will start and idle with the choke on. Once i turn the choke off it idles high for a couple second and then slowly comes down to the point where it stalls out. If i rev it once it gets low the idle jumps back up and then slowly comes down again. Any ideas?
 

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did you poke out all the jets with a pick or wire? the one with all the little holes especially. if you turn the idle speed up does it stay running?
 

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Got a 05 prairie 360. Sat for a while just rebuilt the carb. New gas. It will start and idle with the choke on. Once i turn the choke off it idles high for a couple second and then slowly comes down to the point where it stalls out. If i rev it once it gets low the idle jumps back up and then slowly comes down again. Any ideas?
did you poke out all the jets with a pick or wire? the one with all the little holes especially. if you turn the idle speed up does it stay running?
How did it run before the carb rebuild?
And VTwinKawi's question above ^^^^
 

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Help please

I took my 2007 Kawasaki prairie to the shop because it had a high Rpm sputter after the guy replaced all the gaskets in the carb because he said they are still bad he tired doing the belt light reset thing said he cant do it so now he is telling me the ECU and wiring harness is bad because it wont let him reset the light is there any way this can be true? other things i read says the belt control module is bad? any tips for when i get it back? also if i do have to get a ECU does it have to be flashed for my bike like a car needs to be PLEASE HELP!!!
 

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i would try the manual, seems more likely you have a wire or connection problem. the manual tells you what you are supposed to have at the module
 

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Discussion Starter · #8 ·
Well i started by adjusting the air/fuel screw. Adjusted the idle manually. Got it running pretty good but i think it could run better. I have the a/f screw turned out about four turns which from what ive read is almost double what it should be. The machine also has a custom snorkeler kit. Forgot to add that. On the side of the carb where the throttle is, there is no cover, covering the throttle housing. Should there be one there?
 

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4 turns is too much. that is compensating for some thing else. possibly schmeg in where the AF screw goes?

when rebuilding these, i have always completely disassembled them and soaked them overnight in that stuff you get in a gallon jug from the parts store. its nasty stuff but will leave your carb squeeky clean. be sure to blow out everything with carb clean in a can as that carb dip is funky stuff. then blow everything out with air.
 

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your setup is going to be different because of the snorkel, alot of them let in more air and require richer settings
 

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Discussion Starter · #11 ·
I got the a/f screw turned out about 2 1/2 turns. When i turned it out about three turns think it would help the throttle response it just raised the idle up high. It seemed to be idling pretty well. When i gave it throttle the response didn't seem like it was all there. I put it all back together and then went to start it and it didn't wanna start. So now i'm stumped. Going to pull it back apart tomorrow and see what happened. I pulled the plug out of it just to check it and the plug was blackk!. Brand new plug yesterday.
 

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I did the same as sowandeasy did. I used Berryman chem dip (the neutered version). There are plastic bushings on the butterfly that are left on the body when dipped, so be aware of super caustic chemicals.

The pilot air bleed or bypass ports sound clogged if opening the a/f screw raised the idle. Make sure every port, hole, or opening has a small wire run through.


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you are supposed to set the mix screw by warming the machine then adjust the screw so the rpm goes down when you turn it either way
 

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Discussion Starter · #15 ·
So im suppsoed to warm the machine with the a/f screw seated even if it wont idle. Then once its warmed start turning it out till the idle drops and it idles on its own? You know if theres suppsoed to be any shims in the needle?
 

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Seat the mixture screw and then back it out 2.25 turns. Start engine.

To tune further, make sure engine is up to operating temperature. Then start turning the screw, slowly, and see how it behaves. You want to tune it to be just rich of peak. These air-cooled engines will thank you.

If you start backing out the screw and the RPM starts going up, then stop and then starts going down, you are set. You are just rich of peak. It is better to be rich of peak than lean of peak. If you start backing out and it just starts going down, screw back in till peak, then back out slightly to be rich of peak.

Here is a post from another forum site that explains in detail how these Keihin carbs work. Its a good read.

You will see all the little ports used in the carb and why a little varnish, ethanol poisoning, or gumming can ruin your good ride. Small holes and passageways.

Here is another site that summarizes these carbs.

And here is another pdf discussing these types of carbs (the 32, not the 34 like ours).

Regarding shimming the needle, a lot of people do, especially in the winter. It is another fine tuning option.

A big question, do you have a service manual for the machine?
 

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what he said. the needle same, if there is one its probably good, richens the mix a bit. with the snorkel its like i said would benefit from richer settings
 

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Discussion Starter · #18 · (Edited)
Ok so ive narrowed it down to this. When i spray carb cleaner into the carb it starts and idles fine for about 10 seconds. If i hook up the gas line and turn gas on for it to go into the bowl it doesn't start. So i'm thinking i need to adjust my float? Or add some washers to jet needle. Only thing i can think of. Jets are cleaned. Cleaned them 3-4 times blew air threw them and they are brand new. Seat is good on the carb as well. Fuel is following in fine.
 

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It seems clear there is a fuel starvation issue.

1) Idles with the choke on.
2) Idles with the a/f screw turned all the way out.
3) Idles briefly with carb cleaner.

Based on this information, I think it can be narrowed down to the idle circuit.

There are 2 ports in the front of the carburetor. One is the idle circuit air bleed and the other is the main jet air bleed. Both of these need to be clear, but importantly, the idle one needs to be clear to emulsify and push fuel into the air path. It is the one indicated here:



Does the bike run over idle? Can you open it up? Able to accelerate to wide open throttle? Without the "choke" on? If so, then you have it narrowed down to the idle circuit AND that your float is OK as it is able to flow fuel through the main and needle jets. At WOT, the idle circuit operates, but is negligible in its effect at WOT. However, to be sure, you can measure the float height. It should be 17mm.

Here is a site that has some good info to help in setup. It is for a Harley Performance site (Harley's use the Keihin CV carbs as well). But a lot of the information is similar.

It may be that to compensate for your area, setup, snorkel, etc...4 turns out may be what you need. It is OK if that is the case as long as all other aspects are good. If you can't compensate for a too lean mixture using the A/F screw, then you may need to go up on the size of the pilot jet.

Also, using the choke to get the engine warmed up is OK. I have mine on for about a minute until the engine is warm.

BTW. I don't have all this information on the top of my head and I am still learning. I reached out and listened to the good people here. Everyone helped, but VTwinKawi & VFORCEJOHN were instrumental in me getting my $600 special running like a champ. I also researched tons of sites to be able to work on the carb, a lot of which I have provided the links. You can read about my progress here.
 

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Ok so ive narrowed it down to this. When i spray carb cleaner into the carb it starts and idles fine for about 10 seconds. If i hook up the gas line and turn gas on for it to go into the bowl it doesn't start. So i'm thinking i need to adjust my float? Or add some washers to jet needle. Only thing i can think of. Jets are cleaned. Cleaned them 3-4 times blew air threw them and they are brand new. Seat is good on the carb as well. Fuel is following in fine.
There's much more to cleaning a carb than just poking wires through jets. The entire carb is full of tiny ports and circuits, plus tiny holes in the emulsion tube.
The float level needs to be set to spec as well.
Do you have fuel coming out of the gas line when you pull it off the carb?
 
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