My tachometer has a note saying "PTO-1-540rpm x 1000 rpm." Does this mean that when the engine rpms are 1000 the PTO shaft is turning 540 rpm? I don't want to overspeed my brush hog (which is an obscure, apparently obsolete model with no manual or online info available) but although it does turn fast enough at 1k engine speed to mow, the engine doesn't put out enough power to climb my hilly field at any effective ground speed.
Robin Veerman
Veteran Member
Check it your tractor has an optional 2-speed PTO. Use the 540 pto for field work, and most anything else. Check your owners manual for related information.
The manual is of little help regarding PTO operation. The PTO is single speed.
RJCorazza, thanks. The tach dial has an arrow pointing to 2500 rpm and I initially thought that was the correct point for PTO operation, but the other note got me doubting that. Do you have any notion what "PTO-1-540rpm x 1000 rpm" means?
Is there any drawback to running the engine at lower rpms for PTO use if the implement is doing the job and the engine is not laboring?
ptsg
Super Member
I think you're mixing things slightly.
"PTO-1 540 rpm" is one thing. The "x1000" is another and belongs to engine RPM. That tachometer is probably marked 1 - 2 - 3, etc. So it's 2x1000 for 2000 engine RPM.
There should be a mark as to where the PTO gets up to 540. Should be the arrow you mention at 2500 engine RPM. That's where most of these smaller engines get 540 rpm at the PTO.
"PTO-1 540 rpm" is one thing. The "x1000" is another and belongs to engine RPM. That tachometer is probably marked 1 - 2 - 3, etc. So it's 2x1000 for 2000 engine RPM.
There should be a mark as to where the PTO gets up to 540. Should be the arrow you mention at 2500 engine RPM. That's where most of these smaller engines get 540 rpm at the PTO.
That makes sense, thanks, the two are on separate lines.
One annoying thing about the PTO operation is the secondary PTO switch on the fender. There is a 3 position switch on the dash, "auto", "off" and "manual", and a push button on the right fender which must also be pressed in. The push button is easily disengaged by a brush of the elbow and I plan to make a hood for it. It's bad enough to have the PTO cut out unexpectedly but I really don't want to have it come on accidentally. Was this a temporary quirk in the series design or do other users commonly deal with this?
ptsg
Super Member
So it has a PTO switch is meant to be close to the operator in case you need to shut the PTO off quickly. This switch is what turns the PTO On and Off.
Then there is the PTO mode selection switch, provides different modes of operation for the PTO and works as follow:
In Manual, the PTO is on every time you have the yellow switch in the On position. Once you press the yellow switch, it turns Off the PTO.
In Auto, the PTO will turn off automatically as you raise the 3 pt to max height or close to. On a gear tractor, it also turns off as you press the clutch. Once you lower the 3 pt, it turns the PTO back on again.
This works very well with low speed/low inertia attachments, like a rototiller, 3pt auger and others. The reason I don't recommend using this mode with high speed/high inertia attachments like a brush cuter, flail cutter or others, is because there is a spring actuated brake in the PTO wet clutch. So you can imagine, a brake trying to stop all that mass rotating mass. It's hard on the brake and will wear it prematurely.
Thanks for the reply. I don't use the auto mode. I just am not a fan of the actuator switch's placement due to the frequent inadvertent shutoff. I guess I could relocate it lower on the fender. but I will probably fabricate a hood to prevent hitting it with my elbow.
