PTO Slip Clutch (cat 1) question?

[blades]

I know it's not really an arb related question but I know you guys are good with this stuff.... I have a Wessex RC120 rotavator and while using it yesterday got hooked into a buried tree stump.... The clutch at the rotavator end of the pto shaft kicked in and there was some smoke from it spinning.

 

I have attached a pic showing the type of clutch that it is.

 

My question is.... I assume this slp clutch will have pads of some sort that wears down quickly, allowing less tension in the springs and then slipping... Is there any way to know if it can just be tightened up? Or should I assume the pads will be totally worn?

 

Cheers in advance

[Rich2484]

To Be honest without looking at the clutch its hard to say.

 

But. They are designed to take some abuse and the smoke would be a warning to the user that something is wrong. Designed so that the clutch will kick in before damage to tractor. Best to check the clutch over but unless they are noticeably worn and the clutch is rattling about there is no real worry there.

 

Not any adjustment as the springs are designed to do any wear adjustment so if these rattle about then the plates need changing.

 

Unless you where sitting there with it stuck in the tree smoking for ages then I wouldn't really worry. Just inspect it and give it a pull and push about.

[blades]

To Be honest without looking at the clutch its hard to say.

 

But. They are designed to take some abuse and the smoke would be a warning to the user that something is wrong. Designed so that the clutch will kick in before damage to tractor. Best to check the clutch over but unless they are noticeably worn and the clutch is rattling about there is no real worry there.

 

Not any adjustment as the springs are designed to do any wear adjustment so if these rattle about then the plates need changing.

 

Unless you where sitting there with it stuck in the tree smoking for ages then I wouldn't really worry. Just inspect it and give it a pull and push about.

 

Thanks for that, it's a big help. It didn't smoke for long... I'd guess 15 secs.

I let it cool down after it happened and checked it over... All seemed fine, went to use it but I noticed the resistance of the soil was now stopping the blades and the clutch was slipping... This is why I thought that 1. I had burnt out the pads or 2. The springs needed a wee tighten??

 

Grateful for your help

[Chrisy B]

You can actually see the friction plates in the picture, it's the 2 thinner discs that are sandwiched between the whole pack, you can probably see these on yours if you look.

 

If the clutch is slipping when in normal use I would try and tighten the bolts until it stops, the plates as with a clutch on a car wear and need tightening if they've had some serious slip, but as with a car the pedal gets higher these have to be manually adjusted. Don't get over giddy though just maybe a couple of flats on each at a time until it stops slipping when buried into normal ground. Too tight and you'll have no slip clutch at all and something else will give, usually gearbox.

 

We borrowed a howard rotavotor on the farm once, back of a 7840 ford a blade came out wedge in the hood and stopped tractor dead from 2000 revs surprisingly everything worked after but made sure we slackened bolts off the get it to slip the readjusted.

 

Hope this helps

Chris

[GardenKit]

As Rich says, they are meant to slip and will smoke when they do. They will do this lots of times.

 

They do however need adjustment from time to time to compensate for reduced thickness of worn discs.

 

This is done by setting the spring length. You should find the length in you operator book.

 

Different lengths are used by different machines depending on the desired torque.

 

It is in fact a good idea to check the clutch occasionally by letting it slip. On machines parked up for a long time the clutch plates can bond to the steel with rust. When I was in Ag Engineering part of the pre season service was to slacken the bolts, spin the clutch to polish the plates and then reset the spring lengths.

 

The grease nipple lubricates the centre hub, not the plates.

[Chrisy B]

Think we are all writing at the same time here.

[blades]

Thanks guys.... As usual you have been a great help.... Very much appreciated!!