Bayou 220 Backfires thru carb

[AtvJunkie]

I inherited a 1997 Bayou 220 that hasn't been run in a while. When I got it wouldn't start and after a little investigation I found out the needle was missing. I put in a new carb rebuild kit, cleaned the tank, changed the oil/filter and added a fuel filter. Now the atv will starts but will only stay running with the choke on. Even then it will backfire thru the carb after 5-10 seconds and stops. I've adjusted the main fuel mixture screw from 1-2.5 turns out from seat. When I installed the carb I set the air mixture screw at 1.5 turns out (hard to adjust when installed). Any ideas what I can do to get this thing to idle normally? Thanks in advance.

[86klf300guy]

hello.....

have you checked for vacuum leaks ?check for a vacuum leak at the carb intake (the rubber boot to the manifold) with carb cleaner and see if the rpms change it it does repair the leak by replacein the oring that is on the intake to head side of the manifold ,or repalce the boot.

also did you take all the jets out of the carb and clean them well?there is a air flow jet it has a few pin holes in the side of it and also make sure you can see light through the center hole of all the jets it will be a tiny hole but hold that jet up in a light and focus your eyes youll see light if its clean good.and also use a good cleaner and a air blow gun to make sure all tem passages are clean in the carb.

one more thing do you have a air filter installed while runnin your machine.sometime these machines need that air restriction to operate correctly.

hope this may help you along -corey-

[AtvJunkie]

I took the carb completely apart and installed all the parts that come with Moose rebuild kit. I cleaned and blew out every passage. I will check the intake gasket tonight to make sure there aren't any leaks. Also, I had the air filter disconnected so I'll hook that up tonight as well.

Does anyone know the factory settings for the two (fuel and air) screws. I've heard 1.5 turns out?

[OtisCampbell]

I took my Bayou 220's carb. apart yesterday and cleaned everything so that it was spotless. When putting it back together, I wasn't really sure if the air pilot screw (I think that's what it is called--it's the one INSIDE the bowl beside the main jet) had an adjustment or if it simply is turned in until it stops. Here's my reasoning for the confusion: The mixture screw that you can access outside of the carb. has a point on the end so the depth actually changes the amount of air that flows through. The adjustment, from what I've read on Kawasaki's site, is 1.5 turns out. In reality, I've read that it can be anywhere from 1.25 -2 turns out depending on altitude, air density, temperature, etc.

The screw that you can adjust INSIDE the bowl (air pilot screw, I think) has what appears to be a jet-like orifice on the outside (with a screw-driver slot) and it has a narrow tube with tiny holes on the inside. There is no taper, no o-ring or no spring to hold the tension...so does this mean you still adjust it out X number of turns like the mixture screw on the outside of the carb or do you just turn it in (gently) until it stops like you do the main jet assembly?

I also have more carb-related questions:

1. The idle adjustment screw basically contacts a wedge-shaped notch on the barrel-shaped thing that controls the air flow into the carb. On mine, it appears that someone over-tightened the screw (or it was seized up at one point) and it galled up the area that it contacts. I think this is preventing me from "smoothly" adjusting the idle to that perfect spot. It's either a tad too low or a tad too high. (The galled-up area is raised, so it causes it to idle higher than it normally would.) Can I simply file this down smooth again so the wedge-shaped area is flat without causing any other problems?

2. I read on someone else's post that you should grease the barrel-shaped thing that controls the amount of air that goes into the carb. (in a traditional carb, this would be the "butterfly"). What type of grease should I use on this? (White lithium grease?)

3. I read that you should move the c-clip down 1 slot on the pin that goes down the center of the barrel-shaped thing inside the carb. Mine was all the way up to begin with--but I'm not sure who put it there. Is 1 slot down the setting from the very top slot?

After getting it back together, it idles pretty good... It has a little bit of a flutter, though...like it goes from 1000 rpm - 1200 rpm every now and then while idling. I've checked for air leaks and can't find any. What else could cause this?

Sorry to hijack the thread and sorry for so many questions.

Thanks,

Otis

[MrGiggles]

Originally Posted by OtisCampbell

I took my Bayou 220's carb. apart yesterday and cleaned everything so that it was spotless. When putting it back together, I wasn't really sure if the air pilot screw (I think that's what it is called--it's the one INSIDE the bowl beside the main jet) had an adjustment or if it simply is turned in until it stops. Here's my reasoning for the confusion: The mixture screw that you can access outside of the carb. has a point on the end so the depth actually changes the amount of air that flows through. The adjustment, from what I've read on Kawasaki's site, is 1.5 turns out. In reality, I've read that it can be anywhere from 1.25 -2 turns out depending on altitude, air density, temperature, etc.

The screw that you can adjust INSIDE the bowl (air pilot screw, I think) has what appears to be a jet-like orifice on the outside (with a screw-driver slot) and it has a narrow tube with tiny holes on the inside. There is no taper, no o-ring or no spring to hold the tension...so does this mean you still adjust it out X number of turns like the mixture screw on the outside of the carb or do you just turn it in (gently) until it stops like you do the main jet assembly?

I also have more carb-related questions:

1. The idle adjustment screw basically contacts a wedge-shaped notch on the barrel-shaped thing that controls the air flow into the carb. On mine, it appears that someone over-tightened the screw (or it was seized up at one point) and it galled up the area that it contacts. I think this is preventing me from "smoothly" adjusting the idle to that perfect spot. It's either a tad too low or a tad too high. (The galled-up area is raised, so it causes it to idle higher than it normally would.) Can I simply file this down smooth again so the wedge-shaped area is flat without causing any other problems?

2. I read on someone else's post that you should grease the barrel-shaped thing that controls the amount of air that goes into the carb. (in a traditional carb, this would be the "butterfly"). What type of grease should I use on this? (White lithium grease?)

3. I read that you should move the c-clip down 1 slot on the pin that goes down the center of the barrel-shaped thing inside the carb. Mine was all the way up to begin with--but I'm not sure who put it there. Is 1 slot down the setting from the very top slot?

After getting it back together, it idles pretty good... It has a little bit of a flutter, though...like it goes from 1000 rpm - 1200 rpm every now and then while idling. I've checked for air leaks and can't find any. What else could cause this?

Sorry to hijack the thread and sorry for so many questions.

Thanks,

Otis

The idle jet is what you are talking about that sits next to the main jet inside the bowl. Tighten it down just a bit, it does not need to be adjusted. The way you adjust that is get a bigger or smaller size new one.

The c-clip should be set in the middle slot to begin with.