I have been having a nagging problem with my 95 Wolverine, I am pretty much convinced that it is carb related,possibly a worn out carb, if that can happen. What it does is when the throttle is blipped, or after you slow down from riding, is rev very high, like the throttle is sticking,but the linkages are totally closed, I have verified with the air box off,no part of the butterfly or slide is hanging up, the cable has slack in it, all linkages are moving freely and snapping closed when released. I have pulled the carb apart to the last little part, cleaned and blown out every passage, reassembled and adjusted float level, needle positions, everything that could affect it. What I have noticed is that when it is revving,if I lift the slide to let more air in,the idle drops, so it is definately getting excess fuel from somewhere. I suspected the fuel enrichment choke circuit, so I replaced the plunger in case the gas was leaking by the seal, but it didn't change anything. I have removed the accel pump rod to make sure it wasn't pulling gas from the accel pump port, that changed nothing. With the air box off, I noticed a lot of gas coming up from around the needle, even at idle, shouldn't the idle circuit be the only part supplying gas at idle, and the needle and accel pump add gas as the throttle is opened? I have exhausted everything I know how to do, so did I miss something, or is the almost 12 yr. old carb shot, and if it is, what can I use to replace it? A Warrior carb is exactly the same,should bolt right up, or should I look into aftermarket, like an Edelbrock Quicksilver, or a different style Mikuni carb? Any thoughts, advice or free parts you want to throw my way? I'm kinda running out of ideas.

 

Did you check the coasting enricher diaphram? That should be on the right side of the carb.

Check about 1/2 way down this page: http://jimrace.com/faq/CVK40.html

 

Yeah, pulled that a couple of times, made sure it moved freely, spring was in good shape and all ports were cleared out, like I said,this is really starting to bug me, fuel is getting in somehow, and I'm at a loss to find out exactly where, I'm no carb expert, but I know my way around the insides, and I think I've checked everything I know, but it seems to be excess fuel getting into the carb and raising the rpms,sometimes it will drop on it's own, or I can keep messing with the idle adjustment and drop it, but then the base idle will be too low, and it runs like crud. It has never acted like this in all the years I've been driving it, that's why I'm having a tough time with this problem. That was a great link, though,GlennJ, thanks for the info, I'll either have to keep tinkering, or start looking for a new carb, maybe mine is all fiddled out, after all the years of rejetting, messing with the accel pump, adjusting linkages, it just wore out !!!

 

Its not excess fuel which raises rpm, its excess air. Check the connections of carb to intake, and look carefully for rips or tears in the rubber manifold.

 

Good call hondabuster. An air leak there would most certainly cause the rpm to raise.

 

I'm sorry, my mistake, I forgot to mention that I also tested quite extensively for air leaks by spraying carb cleaner all around the intake, carb and air box boot checking for any change in idle, even did it while it was revving up, did not make any difference. The reason I am sure it is extra fuel, not air, is that it acts just like when the choke ( fuel enrichment rod) is pulled out, putting extra gas into the carb and raising the rpms to warm up the motor. Also, the rpms drop when the flat slide is raised, giving it more air, so I'm thinking it is leaning it back out, and putting the fuel/air mix back to normal so that the idle drops back to normal levels. Once that happens, it will idle fairly good until you hit the throttle again, not every time, but often, it will rev up and stay there like you are giving it gas. It is almost like once it revs up, it pulls fuel up from around the needle and it is just enough to rev it up, not choke it out. You can see why this is really starting to bug me, not your normal problem.

 

You still have to approach it , with the thought that only air can raise rpms...fuel wont do it. Fuel in excess of available air, only chokes and slows down a motor.
Did you try wiggleing the carb, so the rubber intake flexes, while its running? The hose connector and bolts are snug?
Does this gas tank have a vacumn operated valve? (does it have an off position?). The reason i ask is because vacumn goes to the gas valve on some quads(the ones which have a pri and on and res positions), and The rubber hose going to the gas valve could have a leak.
Is this a cv carb? Is the diapham in the top , leak free?

 

No offense, Hondabuster, but are you familiar with how the choke system (enrichment rod) works on the Warrior/Wolverine? you pull a rod on the side of the carb which opens a port to add fuel after the butterfly, and the rpms do rise, especially once the engine warms up, and then drops back to normal when you push the rod back in, so in this case adding fuel does raise the rpms, I am not adding air when the rod is pulled out. It is acting just like the choke circuit is active, and adding air (lifting the flat slide) drops the idle. I have spent a couple of days on this, and exhausted everything I can think of, but I am sure it is not air that is my problem, but fuel, I have checked everywhere, pushed and pulled on all parts of the carb, sprayed with carb cleaner with absolutely no change in idle, but lifting the slide and adding air does change it, so I am running rich, not lean.

 

No offense taken. I know how frustrating it can be working on stuff that doesnt want to work right.

I rebuild carbs and other quad stuff in my spare time, been doing it for years. Theres almost always a fast idle cam, for when the enrichener is pulled on. Thats why the rpms rise when the enerichener is on...the throttle plate is slightly opened..letting in more air.

Check out this article on vacuum leaks and symptoms.

vacuum leak symptoms

Or this one on a high idle

high idle speed

 

Great thread guys, I am learning lots....