PTO on 4340C

[BMAPLES]

PTO on 4340C is only turning about 200 rpm when it should be 540 rpm. Any ideas?

 

[ptsg]

Under load? Unloaded? Is it actually the tractor PTO shaft rotating slower and not a slip clutch slipping?

 

[Roadworthy]

At the risk of sounding really stupid, how does one know how fast a PTO shaft is actually turning? I can set my rpm to match what the PTO SHOULD turn at that speed but I never really KNOW. I never really thought of it before, just kind of took it for granted.

 

[ptsg]

At the risk of sounding really stupid, how does one know how fast a PTO shaft is actually turning? I can set my rpm to match what the PTO SHOULD turn at that speed but I never really KNOW. I never really thought of it before, just kind of took it for granted.

Hence the 540 number. PTO usually runs at 540 RPM. You then can have the 540E/750 and 1000 RPM options as well, but depends on the tractor.

Tractors usually have a mark on the tachometer for the 540 RPM. Depends on the tractor but usually around 2400 to 2600 engine RPM. So once you set the RPM to that mark on the tractor, the PTO is rotating at 540 RPM.

With tractors with multiple PTO speeds, you'll have different marks on the tachometer. For instance, mine has a mark at 2500 engine RPM for the 540 or 750 RPM (2nd speed). It also has another mark at 1800 engine RPM for the 540E, which is the same speed as the 750 but with the engine turning slower (less noise, wear and fuel consumption).

750 RPM is less common to be used as most implements are either 540 or 1000 rpm.

These PTO RPM are not something you must be dead on 540 or 1000 or whatever. Quite often you can run with less RPM and achieve the same results with a mower or tiller. It's something you can experiment and see whatever works for you.

Most of the times I run the tiller with the engine at around 2100 RPM. With a simple math, we can figure out the PTO rpm: (2100*540)/2500= 453 RPM.

Sometimes running at slightly lower PTO RPM will also reduce some weird vibration from a PTO shaft or a bent rotor of the tiller, things like that.

 

[BMAPLES]

I have a 6' shredder on it and it is rotating about 200rpm without cutting anything. Bogs down as soon as i try to cut. I took shredder off, and pto still is spinning slowly. I believe 250 or so rpm. It was working fine, but i was cutting thick grass. Not sure if that did anything. I onlty have a 540 pto on this tractor. Thank you for any help you can offer. Montana 4340C

 

[BMAPLES]

Under load? Unloaded? Is it actually the tractor PTO shaft rotating slower and not a slip clutch slipping?

With 6' shredder connected but not cutting anything it turns about 200 rpm and with the shredder disconnected, it might make a small difference. It was cutting brush fine for a little while until it just bogged down. Now if i put it on the grass, it stops turning.

 

[ruffdog]

What kind of clutch do you have for the PTO? Foot operated? Is it fully engaging? If a foot operated clutch linkage is rusted up and has no free play, they will act like that.

 

[ptsg]

I believe it uses a clutch pack activated by a solenoid valve and then a switch.

My guess is either the clutch pack is bad, the clamping pressure is not right or maybe the wrong oil was used on the transmission which may or may not cause slipping.

 

[ruffdog]

I believe it uses a clutch pack activated by a solenoid valve and then a switch.

My guess is either the clutch pack is bad, the clamping pressure is not right or maybe the wrong oil was used on the transmission which may or may not cause slipping.

^^^agree......or, a oil leak that has lubed up a dry clutch??????????

 

[ptsg]

^^^agree......or, a oil leak that has lubed up a dry clutch??????????

That would translate is loss of movement.

With independent PTOs, there is a shaft straight from the flywheel to the PTO clutch pack, so every time you press the clutch pedal, the PTO won't stop.