TC35D PTO engagement

[bcrites]

I have been having a problem of sheering the drive shaft bolt on my 5' rotary cutter when engaging the pto. I have broken 2 shear bolts so far during about 1 hour of use. The first time one broke was when I engaged the PTO at around 2000 engine rpm. Then I read the manual which seemed to indicate that the engine should be at low rpm when you engage the PTO then slowly accelerated to 540 PTO rpm. That method usually works but I did shear one more bolt during the day using that method. My experience with the tractor I had before this one, a John Deere 955, was that the PTO could be engaged at any engine rpm and the PTO clutch would slowly accelerate the implement. I thought all independent PTO's worked that way. Is there some adjustment on the TC35D that will allow some slippage when engaging the PTO?

 

[BKColeman]

I had the same problem. When I engaged the PTO on my TC40D for the first time, I sheared the bolt. I thought I must have had the RPMs too high. So the next time, I made sure the throttle was all the way back. Happened again. I learned to feather the PTO switch forward slowly, with the cutter off the ground, and it wouldn't shear... usually. I finally decided it wasn't just me and called the dealer. He looked in the ASIST computer and found that some Class III Boomers had the PTO clutch set w/ too much torque. He sent a tech out to measure it and mine was at 300 ft/lbs. According to spec it should be around 240 or so. The tech adjusted it and it works much better now. I still have to feather it in a little at low RPMs, but it now works as I would expect.

If you continue having problems you might want to give your dealer a call. It was an easy fix that they did on-site for me.

Hope this helps.

--Brad

 

[tc35dforme]

The PTO uses a clutch pack to engage. Just like letting out the clutch on a transmission, slow and steady is best. Runing the lever like its an electric switch will allow the clutch pack to slam on the PTO...no necessarily a good thing.

I find that engaging the brush hog requires a bit more finesse ( ? sp ) than when I engage the lighter mass loads.

No matter what, I agree with Brad...keep the tool from engagement with the ground / grass/ etc until your on PTO and bring up the RPMs

 

[djradz]

My procedure is: Set the engine RPMs to about 1300-1500, move the PTO lever slowly, by not unreasonably slowly, to about it's mid-point, give the mower or brush hog a few seconds to get up to speed, then complete the movement of the lever and finally increase the engine speed to get 540 PTO RPM. Doing this, I've never sheared a bolt or slipped a belt.

 

[bcrites]

Thanks for all the helpful replies. I have now been having good sucess at gently engaging the pto lever at low rpm without breaking shear bolts although the lever on mine is so stiff that it is difficult to move it any without moving it all the way. It is really hard for me to understand why NH went to the trouble to automatically allow a gentle spin down without automatically allowing a gentle spin up. I liked that feature on the John Deere but of course there are always tradeoffs. I like almost everything else better on the Boomer.Bob