PTO Speed Question

[biglittlefarm]

Does the pto speed remain at 540 no matter what the engine rpm?

 

[johnk]

The PTO speed varies with the engine RPM. Should be a double dial inside your tach that shows PTO speed at engine RPM.

 

[johnrex62]

On my L3700SU, there is a small bar on the tach with the notation PTO 540 near it. It correlates roughly to 2250-2400 rpm. It may vary with model, but your tach probably has something similar. That range will result in a PTO speed close enough to 540 to be optimal.

 

[biglittlefarm]

Thanks for the answers.

My tach and hour meter are broken on the L185 I just purchased. Tractor runs great. Wish the tach worked.

 

[Delaware Devil]

I have the BX2360. Tach and hour meter are one digital unit. I haven't seen anything to show me the RPM at the PTO, but the dealer told me to run the engine at 2500, and the PTO will be 540.

 

[biglittlefarm]

So, I guess the next question is......

If you overspeed the engine, does the pto top out at 540 or will it turn too fast?

 

[dex3361]

If you run the engine above the speed that gives the correct rpm then it will be above 540RPM.

 

[rjkobbeman]

Does the pto speed remain at 540 no matter what the engine rpm?

So, I guess the next question is......

If you overspeed the engine, does the pto top out at 540 or will it turn too fast?

The PTO is a direct mechanical connection to the engine. The engine RPM has a direct correlation to the PTO RPM. When the engine is running slow, the PTO is running slow. When the engine is revving, the PTO is humming. If you overspeed yoiur engine, the PTO RPM will be higher.

That is why you are suppose to engage the PTO when the engine is idling.

On my tractor, and 85 HP Kubota, the engine is NOT at red-line when the PTO is at 540... but it is getting there. It is CLOSE to full throttle.

If you do not have a working tachometer, I would just run the engine 3/4 or more throttle. If you find the engine isn't able to pull the load, give it more throttle. (Assuming your implement isn't too much for your tractor to handle.)

I imagine the difference between 540 PTO RPM and full throttle PTO RPM isn't much.... so you probably aren't at risk of screwing up something.

 

[Redgoatea]

The tach on my JD 870 has two PTO marks on it. One at 2600 for recommended speed and one higher for PTO limit. If I went over the limit I'm sure the damage would happen fast.

 

[TripleR]

Your Operator Manual will show the proper engine RPM for both Mid Mount and Rear PTO. On my BX2660 I believe it is 3000 for one and 2800 for the other, Max RPM is about 3300.

Engagement according to manual is at "reduced RPM". I also reduce speed to disengage.