After not being ridden in a couple months, my Kodiak wouldn't start due to no spark. Replaced stator and cdi and while I was at it the coil and spark plug. That fixed the spark issue. It will start now but stumbles a little at idle with a knocking sound coming from the motor. If I give it a little fuel it runs nice and smooth. Full throttle it goes back to stumbling. The knocking sound is constant and follows the rpms. Thought I had bad gas but emptied the tank and filled up with 90 no ethanol and no change. I did disassemble the carburetor before I realized spark was the initial problem. Thinking maybe I messed something up on the air/fuel mix. Would that cause this knocking I'm hearing? Sorry for the long read. Just wanted to lay it all out there. Thanks in advance
01 Kodiak 400 runs rough and knocking
1 - 20 of 44 Posts
Joined
·
553 Posts
does it knock at a higher idle? If not could be just the starter spag. No worries, they make noise if it idles super slow and kind of kicks back.
As for idle and stumble it's most like the pilot jet is plugged, remove it and look it over real close. It will have very tiny holes that get plugged. It will take a small stiff piece of wire to clean. I have used a strand of a heavy gauge wire.
It 'knocks' all the time, speeds up and slows with the motor. Hearing is some more today, maybe knock is the wrong word. I should call it a loud tick, like it's low on oil, which it isn't, but louder. Another thing, just a few minutes of running the way it is completely fouls the plug. Seems like to me that would indicate plenty of fuel getting to chamber but it's not igniting.
Joined
·
553 Posts
Oh ok could very well be a valve ticking, check the adjustment.
fouls like black? Check out the carb again. One time on my warrior the main jet came loose and it flooded at certain RPMs, very odd.
Also, double check your float needle and seat, if it's leaking buy an OEM one not a cheapo, trust me!
Use a clear tube on the drain and run it up a bit to see where the fuel level is. I'll try to find a link to a site to show you what I mean. It's a super handy way to watch the fuel level. I leave mine on there all the time. The level should be right at where the bowl meets the carb body, no higher. I have found a little lower is ok too.
Checking, Measuring, and Adjusting Motorcycle Fuel Levels in the Carbs - MotorcycleZombies.com
Is your fuel level in your motorcycle carbs correct? Learn how to measure and adjust it here.
www.motorcyclezombies.com
Ok finally had time to check the fuel level. It's above the bowl, but the tube on the inside of the bowl that lets the fuel out the drain is the same height above the bowl. Maybe fuel level can't be checked on this particular carb using that method? I have it apart about to check the jets and I found another way to check/adjust fuel level with carb disassembled. Appreciate the help, sure hope it's not valve out of adjustment, no clue how to even do that. Is that very likely anyway? that the valve could get that bad out of adjustment so quickly.
Adjusted fuel level down just a bit, per the manual. It seems to idle a little better, but still ticking and anything more than half throttle it still stumbles. Warrior Scott mentioned the valve could be ticking. I'm guessing that the valve clearance?
Adjusted valves per the manual. The ticking might have quieted down a little it's hard to tell. It still won't rev correctly. Gonna try to adjust valves again. Is there something simple I'm missing? I read about checking timing but the manual didn't really make sense on that. Would that cause these symptoms?
Joined
·
553 Posts
Mine runs best with the level just below the bowl.
You can't adjust the timing.
How exactly is it acting now?
Is the plug clean? Try a new one and see what happens.
Manual says fuel level should be 4-5 mm above bowl. Which is where it's at. Its runs about the same as before I adjusted the valves. I might try a new plug tomorrow just to see. This one is a brand new champion. Should I get an ngk?
Joined
·
553 Posts
NGK is the standard but I doubt it will matter.
So you said it just idles bad still it almost has to be a vacuum leak or the carb is plugged, something like that.
Does adjusting the idle mix help? Usually the problem is in that circuit or the pilot jet circuit.
Those holes in the pilot are so very small it's easy to miss. I've used strands of a heavy gauge wire to clean them out before.
It does idle pretty good now. But I still can't go above half throttle without stumbling and choking out, and still ticking. I cleaned every jet as good as humanly possible with a small strand of wire and carb cleaner, letting it soak in. Maybe I need new jets? When I went to adjust valves again last night, they seemed to be in the same position as the first time I adjusted them, almost no clearance. Why would that be?
Joined
·
553 Posts
Oh, your first post just said bad idle (I think).
If it fails above half try raising the main jet needle one slot.
Did it run right before it sat for a while?
Does it have a stock pipe?
Check for good flow from the tank by simply pulling the line off the carb and see how it flows. It could very well have gunk on the filter in the tank on the pet cock.
That is strange about the valves. Did you set them cold or warm? Go by the book. But either way there needs to be some clearance, maybe add a bit this time.
Yes it idled a little rough right after I fixed spark issue. Now it idles fine. It ran great before it sat and it has a stock pipe. I will check fuel flow from tank. Hadn't thought about that. After the second time I adjusted valves it runs a little better above half throttle but still not quite right. It runs rich and lot of blue smoke sitting still when revved up. Not sure what you mean about raising main jet one slot. Didn't notice any way to change jets in carb.
Joined
·
553 Posts
Blue smoke is oil burning. Black is gas. As for oil has it been changed recently? If it's been a long time it might help the oil burning.
Main jet needle. It should not need to be adjusted if it ran good before though.
Joined
·
553 Posts
It is not likely the valves as long as they are not too tight.
Check for black smoke when it misses at high rpm. If you feel the carb is clean and you have no black smoke I would try raising the needle one notch.
But only after all else is checked like good flow from the tank. No air leaks. Ect...
The hose between air box and the carb was split at the bottom where a vacuum hose going to carb attaches to it. It's discontinued. I ordered one that goes on the 03 and up Kodiaks. Looks like the same part. Probably be next week before I get it.
New boot was almost a half inch longer than the original. I was able to make it fit. Didn't fix the problem though. I dropped the needle one slot and it runs better than it has since this whole thing started. Full throttle is almost perfect, but it tends to stumble as soon as I throttle up almost stalling out, then it takes off fine. I don't know what to do anymore. I called a local shop. He can't look at it til next week. Probably just gonna let him have it.
Joined
·
553 Posts
Take a good hard look at the pilot jet. Those holes are SO SMALL it's easy to miss them being plugged. Cleaning them with carb cleaner won't usually work, the stuff in the holes will be like glue, it has to be poked out with a small strand of stiff wire.
1 - 20 of 44 Posts
