Hello all - looking for clutch troubleshooting advice. I recently aquired a 96 FourTrax TRX300FWT with a failed clutch basket and main drive gear. I am a driveway mechanic but I've never rebuilt a clutch. I purchased used clutches off ebay, new gaskets and seals, and replaced both clutches. Watched a few videos that showed how to dis-assemble, but very few (good) re-assembly instructions. Only after I put everything back together did I locate the factory service manual online. My problemm is .... engine runs fine, but everytime I put the 4-wheeler into 1st gear at idle, it lurches forward and stalls the engine. I don't hear gears grinding, and the ATV shifts into gear easily (I can hear the 'click" when I raise the shifter), but when I release the shifter the ATV lurches forward. I have tried adjusting the clutch using the clutch adjustment screw. The screw does not "feel" like it's doing anything, even though I turn the screw through it's full travel and I can see the screw moving in and out of the crankcase. I would welcome input on potential causes. I know I have to open the crankcase back up - hoping to only do this one more time if I check all possible causes while I'm in there. When I figure out the problem, I'll post the solution.

Over-torquing the 4 bolts that hold the clutch lifter plate? Most likely the problem (my opinion). I know I torqued more than the 9 ft-lb spec. Live and learn.

Sezied or broken clutch adjustment screw? Screw turns fine, moves in and out, but i don't "feel" the screw touching any resistance against the clutch.

Faulty used clutches (or insufficient oil soaking)? I bought the clutches on ebay from an ATV salvage company. If the clutches are too dry will they cause my problem?

Improper re-assembly of a bearing, lever, etc?

Other ideas? Any details I can provide to help?

Thanks in advance.

 

Could be a seized one way clutch bearing

Idle is good?

 

Yes, one way clutch, not the multiplate clutch which you seem to be referring to. Most likely that you have put it in the wrong way round. On the 300 the kick start goes through it, so if it is the wrong way round, the kick start won't turn the crankshaft. As doctorquad also wrote, idle has to be slow enough for the centrifugal clutch to be disengaged when you put the gearbox in 1st or reverse.

 

Thanks guys. Quick update. I fixed the issue(s). I didn't see the troubleshooting tip on using the kick starter turning the crank until after I fixed it (great suggestion). Through a combination of used parts off ebay (suspected faulty) and my inexperience, I believe I had two problems. One way bearing installed wrong direction, plus faulty (used) primary clutch.

Some people may know this, but just in case - here is another good way to troubleshoot which clutch is the problem. If you lift the foot shifter upwards from neutral, and hold it "up", and the ATV lurches forward (in gear), there is a problem with the primary clutch. If the ATV stays in neutral until you release the clutch back to it's "relaxed" position, and the ATV lurches forward (in gear), you have a problem with the centrifugal clutch.

Great forum !!

 

Good to hear you got it fixed. However, unless you have assembled it wrong, it is extremely rare for the centrifugal clutch to stick. Usual problem is it is worn out, not easy to tell then, which clutch is slipping. As you have to take them off anyway, you can see if the shoes are worn out once you take the cover off. Always best to check the plate thickness of the multiplate clutch too, while you have it off.