Clutch enaging and disengaging at idle

[defiant1]

Got my engine (1992 Arctic Cat 550 EXT Special) to start on the first pull

. But in the tuning process I noticed the clutch was engaging and disengaging on its own (between 2800-3100 rpm). It would load up 500rpm when the clutch engaged and then the rpm would go down when it disengaged.
It would repeat this about 10 times before it disengaged for good and idled around 1800 rpm. Along with that, the belt is either slipping or dragging as there is a burned rubber smell as well.

So, where do I start? The drive clutch looks to be a 9 tower.

d1

 

[Idcatman1]

The last part about the burned rubber smell is easy. If the clutch is engaging but the sled isn't moving it is going to burn the belt. The other part isn't so easy. Is the throttle cable hanging up a little? Maybe holding the throttle open until vibration or something else lets it release and go back to normal idle? Could also be some gum or varnish on the throttle slides making them hang up a little. It doesn't sound like a drive clutch problem to me, I am thinking more likely carb or cable trouble.
Let us know if you find anything.

 

[diggerdown]

Broken clutch spring, no way should it be engaging at 2800 unless the spring is broke or totally shot. If the clutch is dragging it would go up and down in rpm. You may still have a carb issue on top of the clutch problem.

 

[backcountryislife]

yeah, my vote would be broken primary spring.

 

[defiant1]

Thanks for the replies. I will check out the spring on the primary tomorrow night after work. It looks fine sitting in the clutch housing, but I will have to take a better look. Thanks again.

d1

 

[Idcatman1]

I thought broken spring at first too, but it probably wouldn't disengage even at 1800 rpm. Still won't hurt to check.

 

[RCR3]

What is the low idle RPM?

 

[defiant1]

What is the low idle RPM?

If you are asking me what the normal (factory) idle is supposed to be; it is supposed to be set between 2000-2500 rpm. It will idle at 1200 rpm but it has some bogging issues at that point.

I have not been able to check the primary yet, it is looking like the weekend at this point.

d1