Re: Sluggish PTO on X748
I know that is correct, but the diesel has so much torque half throttle works fine. I figure it is easier on the PTO. I disengae at half throttle too as I figure it is easier on the PTO brake. Maybe I'm wrong about it but I've been doing it for over 10 years.
On a diesel it doesn't matter. I've engaged my mower blades at idle with no issue. On a gasoline engine you'll stall it.
It has more to do with the rpms and the hydraulic pump speed (which equates to fluid volume being pumped) at engagement than it does with whatever the torque is at xxx engine speed.
I do wonder sometimes about what effect the engine speed (and therefore flow from the trans pump) has on the brake when you shut off the PTO, mostly when it has to stop a heavy load. I have a DR wood chipper that I run off my 540 PTO. Tractor does very well powering it, but you definitely have to have the engine at full speed when you engage it, the flywheel on the chipper weighs 50 pounds, and the diesel bogs a bit while the flywheel spins up to speed. If you shut the PTO off at full throttle, the brake has to slow that big chunk of rotating steel from its full speed, which I can't see as being good for it over the long term. I usually slow the throttle gradually and let the engine slow the flywheel until the engine is about 1/4 throttle, then shut off the PTO. When you stop the mower deck, all the rotating parts together don't have the mass that flywheel has, so not nearly as much load on the brake.
'09 JD 2520, CX200 loader and 62D deck
LP RTR0550 rototiller
?? 60" box blade
Simplicity 10" plow adapted to 3-pt hitch
3-point PTO DR wood chipper
'02 JD GT235, 48C deck
'84 JD 318, 50" deck
'86 JD 214, 46" deck
'86 JD 212, 38" deck
'08 X748SE, gone but not forgotten