Slip clutch Adjustment

[scsims]

I have a Hawkline/International brush cutter with a 40hp gear box. My tractor has 45hp to the pto and I'm wanting to make sure that my slip clutch is set up correctly.

The manual uses spring length to determine the hp rating and torque lbs. I won't go through all the different recommend settings but I measured mine and the springs were 28mm +/- a couple thousanths of an inch on a couple.

28mm = 30HP and 3501 lbs of torque.

I haven't had a problem cutting anything with it so far although the setting seems a little weak for the gear box and tractor.

Should I adjust it to 27mm or 40hp (4668 torque lbs) or leave it alone as long as it isn't slipping?

 

[kebo]

Trial and error is the best method. The measurement on the springs will get you close, but you just need to test it to see if needs more or less tension on the springs. How do you test it? Raise the bush hog up and back it over a spot of real heavy grass/brush, engage the pto and run it up to speed. Drop it down fairly quick and see if it slips (you can make a chalk mark on the inner disk and the plates before you start). If it slips a little bit, then I would say tighten it up just a tad and repeat. It shouldn't slip under normal or heavy mowing, but obviously it should slip if it hits something solid. The trick is finding the "sweet spot" for the right amount of tension on the springs.

 

[boomer1025]

Just make sure it's not froze up and won't slip. Then I'd re-set it at 28mm. The gear box might take 40hp, but what about the rest of the piece of equipment it's connected to ? Your torque reading don't look right, a 600hp cummins only put outs about 1/2 or alittle less then what you have for 40hp.

 

[daveinnh]

I would agree w/ Kebo.

After putting a slip clutch on a rotary mower a few years ago; someone here recommended exercising (loosening then tightening) the clutch each spring. I do this as Kebo said.

Still beats replacing shear pins.