Kawasaki Mule variator
 

I have to repair a 4010 Mule. The symptoms are the gearbox changes down suddenly when going down hill. The effect is similar to slamming a manual shift car into bottom gear, i.e, a sudden slowing and the engine revs up. I was told the problem would be the back variator pulley bushes worn. However this design, which is both clutch and gearbox, is quite different to the Suzuki and Yamaha variators that I am used to. The front pulley is taper-locked onto the flywheel and needs a special tool to remove, and the rear pulley seems to be held together by a large circlip. I suspect if I get the circlip off, the assembly will fly apart due to spring pressure. Has anyone else had one of these to pieces? Is there any way round the need for the special tool, and could anything else cause these symptoms besides worn pulley bushes, as they seem to be OK?

Strange that I didn't get any replies to this one, as apparently it is a known fault that should have got a recall from Kawasaki, but didn't. Early 4010 Diesels were fitted with rear pulleys that had been badly machined. The sliding surface wasn't smooth enough and wears the bushes in the centre of the sheaves rapidly. A local Kawasaki dealer put us right and sold us a reconditioned rear pulley set, already built up. The belt can be prized over the rear pulley without removing the front pulley at all, so no need for the special tool. Once removed, you can check your rear pulley for wear by winding the sheaves in opposite directions, this takes spring pressure off and you can feel the play in the bushes.

Hi Merryman,
I am in Australia, I own a 4010 Trans Diesel and I had the same issue as you.

I rebuilt both the drive and driven CVT's in an attempt to rectify the problem. I installed a new drive belt as well and put it all back together and the issue was the same. I still had the sudden slowing or harsh deceleration.

Eventually I removed it all again and discovered that the issue is indeed with the driven or secondary CVT. I rotated the sheave on the driven CVT whilst it was still in place on my Mule and you could clearly see the excessive sideways movement.

I installed another set of bushes into the driven clutch and measured it on the bench and these bushes were already over their service limit (according to the Factory Workshop Manual) and they hadn't even done anything!

I decided to trash the original driven CVT and I purchased and installed a new one. I considered having the CVT built up and machined, but I didn't have any data to know what measurements it should be machined too.

Before I installed the new driven CVT, I dismantled it and coated the sliding surface with a dry moly lubricant and left it to cure for 8 hours. The two bushes in there appear to be self lubricating so I only sprayed the surface that these bearings slide on.

This has solved the problem and my Mule is now back to how it was when it came off the showroom floor. I also noted that the complete CVT driven assemblies have had successive part number updates.

That says something.

Regards,
Brian
Australia

Glad your new pulleys worked. As it happens our "rebuilt" one didn't, at least it only worked for a month or so. The boss took it back to the "expert" who gave us another rebuilt one. This seems to be OK, as yet.

Thanks,
Wow....so the rebuilt one wasn't bullet proof? That's interesting reading.

Just to clarify..........when you say "pulleys", it was just the driven clutch that I replaced with a brand new assembly.

The drive clutch (primary clutch) was left "as-is" after I had rebuilt it. I have read on other Forums where 3010 owners have had this issue, but have remedied it by just replacing the two bushes in the driven clutch.

But........this hasn't appeared to work for those with the same issue and own 4010's.

There appears to be plenty of Mule owners who are suffering from this issue.

There is a dry Moly clutch lube available in the USA that CVT owners swear by. I'm not sure if I am able to say the name, but this product isn't available in Australia. I sourced a spray can of an equivalent product from a bearing supplies here. It's widely mentioned on other ATV Forums.

I've read where you can apply it sparingly to prolong CVT life.

I hope my brand new driven clutch lasts longer than a month, unlike yours ha!

Thanks for your reply.

Sorry I should have written pulley rather than pulleys. The "expert" said that Kawasaki sent out improved rear pulleys if the original went under warranty, which is why he had a few which he rebuilt and sold on exchange. I guess your new one would be the improved type. Kawasaki seem to be "loosing it" over here, the Quads have been poor sellers since they dropped the KLF300, and now the mule is loosing out to the John Deere 855 model, possibly because of the variator problems.