Kawasaki Motorcycle Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
I have a '97 Prairie 400 4X4. Starting about a month ago it became difficult to start, stumbling while starter engaged and then backfiring out of the exhaust.

I recently disassembled carburetor and cleaned and installed a new carb kit with new jets, etc., adjusted the float, adjusted the intake and exhaust valves, new gas, new oil.

After putting it all back together, I had the same trouble getting it to start (backfiring, etc.). I swapped the plug for a brand new one and was able to get it started. Once it cleared itself, it actually was idling very smooth until I gave it a little throttle and it bogged. While idling, I took off the air cleaner and sprayed some Seafoam down the throat while revving it. This helped and I was finally able to get full throttle. I let it idle for a while and noticed that it was putting out quite a bit of black smoke at idle and when first revved. At higher rpm's it disappears. After a few minutes of running, it started to idle rough and finally it wouldn't idle at all.

After it killed I was able to get it started again but I still couldn't get it to idle. After it killed again, I couldn't re-start it. Pulled the brand new plug and it was covered in thick black soot. Swapped it out for the original plug and back to the same no-start, backfiring out of the exhaust thing.

It's obviously running rich, but I can't figure out why or how the fuel is getting dumped in. Carb mixture screw is adjusted to manufacturer recommended setting, carb floats are to manufacturer spec. (I even tested it on the bike with a clear tube off of the dump spigot and it appears fine). Adjusted intake and exhaust valves to within manufacturer's specified range.

I'm out of ideas and hope someone on this board can help. Could this still be a carbon buildup issue on the valves? I've seen comments regarding a stuck pressure release valve, would that cause this rich condition? I noticed that the carb (while mounted) is at a slant with the rear end of the carb being slightly higher than the front end, could this be dumping fuel (I don't know that there is any other way to mount the carb, though)?

Any thoughts?

Thanks.

Jim C.
 

·
Registered
Joined
·
3,787 Posts
Check your starting plunger (most people call it a choke). It is a small valve located up on the top side of the carb, just below the diaphragm cover, and when open it lets fuel rush in so the unit will cold start. If it is not properly adjusted or is stuck open it will run rich and can create hard starting once the engine has been flooded.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #3
RCW,

Thanks for the reply. The starter plunger is brand new. Old one stripped out and I was hoping that it was the culprit when this problem started. Actually, when I first got it running, it ran very smooth and when I moved the lever on the hand grip to "Choke" it actually revved higher. When I moved it back, it slowed. After it started running bad again, moving this lever didn't seem to have any affect.

You mentioned an adjustment for this starter plunger, is there one?

Thanks.
 

·
Registered
Joined
·
3,787 Posts
On the cable at the carb end is an adjustment. Try disconnecting the cable from the plunger arm and see if the problem goes away, also make sure that you put the spring on top of the valve when you installed the new plunger.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #5
RCW,

Wanted to get back with an update. You certainly steered me in the right direction. It ended up being related to the starting plunger. Although it was brand new, it wasn't functioning properly. Once I re-installed it, all was better. Now my Prairie is back to running good again. Actually it's better since I adjusted valves and replaced some drive train components.

Again, thanks for steering me in the right direction. Sometimes the obvious is overlooked until someone makes you think about it. I really appreciate the help.

Jim C.
 

·
Registered
Joined
·
344 Posts
Here's one for you, as I have a 400 4x4. I've had not on problem with it in 11 years. One day, while in CA. (Arbuckle and I-5) it wouldn't run well no power. I checked the carb, etc. and everything was OK. What had happened, after I heard a rattle in the intake air pipe, was that while shooting ground squirrels with my 12 guage, two empty casings had dropped down in front of the gas tank and went in the intake pipe. One didn't make enough difference, but when the second got in there it restricted it enough to cause a problem. Now, top that one!!!!!!!!! I wonder if I'm the only person to have that happen? I shot allot of squirrels and ran down and shot alot of coyotes on either side of I-5 just S. of Arbuckle. Still got the 400 and now have a B.Force. in MO.
 

·
Registered
Joined
·
85 Posts
I have a '97 Prairie 400 4X4. Starting about a month ago it became difficult to start, stumbling while starter engaged and then backfiring out of the exhaust.

I recently disassembled carburetor and cleaned and installed a new carb kit with new jets, etc., adjusted the float, adjusted the intake and exhaust valves, new gas, new oil.

After putting it all back together, I had the same trouble getting it to start (backfiring, etc.). I swapped the plug for a brand new one and was able to get it started. Once it cleared itself, it actually was idling very smooth until I gave it a little throttle and it bogged. While idling, I took off the air cleaner and sprayed some Seafoam down the throat while revving it. This helped and I was finally able to get full throttle. I let it idle for a while and noticed that it was putting out quite a bit of black smoke at idle and when first revved. At higher rpm's it disappears. After a few minutes of running, it started to idle rough and finally it wouldn't idle at all.

After it killed I was able to get it started again but I still couldn't get it to idle. After it killed again, I couldn't re-start it. Pulled the brand new plug and it was covered in thick black soot. Swapped it out for the original plug and back to the same no-start, backfiring out of the exhaust thing.

It's obviously running rich, but I can't figure out why or how the fuel is getting dumped in. Carb mixture screw is adjusted to manufacturer recommended setting, carb floats are to manufacturer spec. (I even tested it on the bike with a clear tube off of the dump spigot and it appears fine). Adjusted intake and exhaust valves to within manufacturer's specified range.

I'm out of ideas and hope someone on this board can help. Could this still be a carbon buildup issue on the valves? I've seen comments regarding a stuck pressure release valve, would that cause this rich condition? I noticed that the carb (while mounted) is at a slant with the rear end of the carb being slightly higher than the front end, could this be dumping fuel (I don't know that there is any other way to mount the carb, though)?

Any thoughts?

Thanks.

Jim C.
I was having problems with my 97 2510 Mule running roughly a couple years ago. The Kawasaki dealer told me to run a can of Sea Foam through the tank. he said that is what they do. I did it and it took care of the problem. I guess it is good stuff. I use it in my motorcycles now. I run a can every year.
 
1 - 7 of 7 Posts
Top