Mowing Disengage PTO before idling down?

[BeezFun]

When using my bushhog I usually lower the throttle to idle while the PTO is still engaged because that stops the blades faster. I notice when I do this that the engine makes a slight sound similar to when you use an engine brake, except of course there's no engine brake. Is that hurting anything? It's kind of like that barking noise diesels make when they first start up. I'm imagining the inertia of the mower driveline is trying to force the engine to run faster than it wants to given the small amount of fuel being injected with the throttle set at idle.

 

[leonz]

Disconnect it at speed and then dont worry about it as you are adding load other wise.

It adds wear to the power train where the disconnect allows the implement to slow at its own rate of speed whee the inertia and gravity simply does its job

 

[Larry Caldwell]

I doubt that it makes a difference. Idle down before you engage the PTO.

 

[radman1]

It is best to idle down before shutting of the pto. Why? Because of the pto brake. Every modern day pto has a brake. Safety device to stop the pto faster than just "coasting" to a normal stop. When your coat is being wrapped into the pto shaft and your buddy shuts off the pto, you will be greatful for the pto brake. High speed rpm and lots of pto inertia, put more strain on the pto brake and it will wear out faster. My large ag tractors with pto brake can undergo a lot of braking with 1000 rpm ptos. I can actually push a button on my tractors to override the pto brake and allow the pto to coast to a stop.
Many times when mowing, I will idle down, disengage the pto and keep moving the tractor/mower into uncut grass, to help slow down the pto and prevent more wear on the brake.

 

[radman1]

Forgot to add, the pto brake is why you see the shaft of the pto stop very quickly even without a pto shaft attached. If you ever see a modern tractor take a long time to stop the pto from turning, the pto brake is probably worn out.

 

[KennyV]

radman1 is right ...the pto brake.
My L4200 has it and I would guess the sound you hear is the brake being worked hard... KennyV

 

[RickB]

Disconnect it at speed and then dont worry about it as you are adding load other wise.

It adds wear to the power train where the disconnect allows the implement to slow at its own rate of speed whee the inertia and gravity simply does its job

That is incredibly bad advise if the tractor in question has a PTO brake. Shutting the PTO off at speed while using an implement with a high inertial load will wear the PTO brake exponentially faster than closing the throttle, then disengaging the PTO.

 

[LD1]

It hasent been metioned yet and I am not sure weather his tractor has one or not, but mine and most others do.....what about the overrunning clutch????

The engine can only drive the PTO, not the other way around. SO if it bushhog wants to run 540 rpm and you Idle the engine down with the PTO still engaged, the engine WILL NOT try to slow the PTO at all. So there is no difference between Idling down and then shutting off, or just disengaging at speed. Either way the brake is the one doing the work. Unless you slow the engine down at about the same speed as the BH would slow down on its own. But that would take forever.

 

[DavidAubke]

I assume my little BX2350 does not feature a PTO brake. I was never aware of such a thing and have always disengaged before throttling down. The mower seems to spin down on its own with no assistance from any brake.

 

[Volfandt]

I always reduce rpm before I engage/disengage the pto. As was pointed out, theres a braking assembly involved and by reducing rpm you lessen the wear and tear on all the involved assemblies. As for slowing down to idle I prefer alittle more rpm than idle as it can stall when engageing and lug when disengageing, both of which are bad

The clicking sounds etc are probably from the slip clutch doing it's designed thing.
Dave