Putting a slip clutch on a gearbox with a shear pin shaft?

andrewj · Dec 3, 2006

hi folks. I'd like to buy a 6 ft king kutter rotary cutter, and I want to use my slip clutch instead of teh shearpin that comes on it. problem is, the shaft in the gearbox has a shearpin.

This cutter looks to have a 40-50 hp gearbox, very sturdy, and is 699.00. I really want to get it but am frustrated at finding it had a shearpin.

what could I do?

andrewj · Dec 3, 2006

I want to clarify the shaft on the new unit is smooth except a hole for the pin, and my slip clutch hole is splined.

ksmmoto · Dec 3, 2006

In TSC and other supplies I have seen smooth bore slip clutchs. That's what I put on my KK Brush Hog and Finish Mower. The spline shaft clutch will not work on a smooth shaft.

ksmmoto

BTDT · Dec 3, 2006

Tractor supply should have some flyers/brochures on the KK cutter, look and see if it has an 800# you can call and ask them if they offer what your looking for (or see if anything on their website), you may have to fabricate something to make it work if they don't. This should start another war on "how" it should be fabricated.

Highbeam · Dec 3, 2006

You just need to get the proper slip clutch. Agri-supply sells standard ones for a good price. My mower has a slip clutch which was added by the dealer to a smooth shafted gear box. You replace the shear pin with a stronger bolt and let the clutches do the slipping.

This is good news.

greg_g · Dec 4, 2006

Unfortunate that you didn't think of that before you bought. But all is not lost. If you want to use your existing slip clutch, you should first confirm that it's got a compatible horsepower rating. Mine for example, is only rated for 25-50 PTO hp. The clutch tensioning springs aren't adjustable above or below that. If so - depending whether you got the 40hp or 60hp transmission - you might get a splined input shaft from KK. That info should be towards the rear of your KK owner's manual.

Alternatively, abandon your old slip clutch driveline and replace it with the smoothbore/shear pin style. Personally, I don't like these - since the bolt with which you attach the clutch to the input shaft often turns out to be a shear pin. Plus, the holes eventually get rounded out - which in turn does unpredictable things to the slipclutch response to torque. Given a choice, I'd take a splined slipclutch anyday

Or - if you haven't used the mower yet - just take it back to the retailer and getcha the one ya wanted in the first place

//greg//

N80 · Dec 4, 2006

If you haven't purchased it yet, go to the KK website. I'm pretty sure you can order a unit with a slip clutch. TSC should allow you to order one through them.

kossetx · Dec 4, 2006

I'g gathering you have not purchased it yet. Tracor supply can get one with a sc, or if it is too much more to order it, they should sell one to fit it there at the store. Measure your shaft and see if your sc will fit. The pin will just hold it on. 699 is a good price. They are 899 here in tx.

MrJimi · Dec 4, 2006

When I was looking at KK this past summer, the light duty came with shear bolt and Heavy duty came with slip clutch and I would think for the cost difference and the heavier construction, I would go for the heavy duty version
Jim

Highbeam · Dec 4, 2006

Even if you order one from KK with a slip clutch.... how do you know that you'll get the splined version? If I was Mr. KK making a 699$ RC I would only want to stock and use one model of gearbox for all mowers.