B2601 shuddering when starting Del Morino FP 132 Flail

Burra B2601HD

New member

Equipment
Kubota B2601HD, Del Morino FP132 Flail
Oct 12, 2021
2
0
1
Googong, NSW, Australia
G'day Guys,

Long time lurker with a newbie qstn. I know that I should be in lower idle to start up PTO implements. However, anything less than almost 540RPM on the PTO results in the B2601 shuddering and blowing a lot of exhaust. I basically have to raise the throttle instantly or I stall. The flail is a Del Morino 132, which is within the 2601's capacity. Any thoughts? Thanks in advance
 

NCL4701

Well-known member

Equipment
L4701, T2290, WC68, grapple, BB1572 box scrape, Howes 500, 16kW IMD gen, WG24
Apr 27, 2020
2,489
3,508
113
Central Piedmont, NC
If you have a clutch in it such that you can engage the PTO at high engine RPM and ease into a soft start there’s nothing wrong with engaging at high RPM.

If it’s a push button that slams in with no way to ease it in (like my Kubota) I’m interested to hear suggestions, too. So far as I know that pretty much must be engaged at idle. It’s the only thing long term I really don’t like about mine although it’s caused me no real problem.
 

Burra B2601HD

New member

Equipment
Kubota B2601HD, Del Morino FP132 Flail
Oct 12, 2021
2
0
1
Googong, NSW, Australia
G'day NCL, thanks for the input. Not sure there is a clutch. The Kubota just has a lever which I think engages the shaft instantly - I stand to be happily corrected by those who know more.
 

hodge

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Lifetime Member

Equipment
John Deere 790 John Deere 310 backhoe Bobcat 743
Nov 19, 2010
2,849
367
83
Love, VA
It sounds like the engine is loading up- have you checked to see if your flail is turning freely? There shouldn't be hardly any load on the engine to engage the implement, unless rotation is restricted.
 

SDT

Well-known member

Equipment
multiple and various
Apr 15, 2018
3,084
923
113
SE, IN
G'day Guys,

Long time lurker with a newbie qstn. I know that I should be in lower idle to start up PTO implements. However, anything less than almost 540RPM on the PTO results in the B2601 shuddering and blowing a lot of exhaust. I basically have to raise the throttle instantly or I stall. The flail is a Del Morino 132, which is within the 2601's capacity. Any thoughts? Thanks in advance
Welcome to the real world of starting high inertial loads with HST (or electric over hydraulic PTO clutch) tractors.

The trend in HST tractors is to delete the foot clutch to reduce costs. Without one, it is usually not possible to feather engagement of the PTO.

Increase engine RPM and engage abruptly or stall. Your choice.

SDT
 

NCL4701

Well-known member

Equipment
L4701, T2290, WC68, grapple, BB1572 box scrape, Howes 500, 16kW IMD gen, WG24
Apr 27, 2020
2,489
3,508
113
Central Piedmont, NC
Welcome to the real world of starting high inertial loads with HST (or electric over hydraulic PTO clutch) tractors.

The trend in HST tractors is to delete the foot clutch to reduce costs. Without one, it is usually not possible to feather engagement of the PTO.

Increase engine RPM and engage abruptly or stall. Your choice.

SDT
I’ve been quite surprised at the performance of the electric/hydraulic PTO engagement at idle with rotary cutter sitting in heavy grass and chipper with 100lb +/- flywheel. If I slammed those in snatching the clutch at idle with our older gas gear drive tractors they’d stall out, no question. The electric/hydraulic seems to have quite a bit of torque even at low RPM. I have a rather poor understanding of what is actually driving the PTO on the electric/hydraulic PTO. Don’t really know if it’s driving off gears to the output on the engine or what. Could just be the “governor” on the Kubota is fast enough to adjust fuel flow to keep up with demand whereas the mechanical governors on the old gassers have enough lag that the motor is dead before they catch up. Have several times wondered about that. Kind of hard to imagine the intrinsic inertial load of a flail is more than the inertial load of a chipper flywheel or rotary cutter sitting in 3’ grass but I don’t have a flail so maybe it is.
 

Elliott in GA

Well-known member

Equipment
LX 2610SU w/535,LP RCR1860,FDR1660,SGC0554,FSP500, DD BBX60005
Mar 10, 2021
618
591
93
North Georgia
FWIW, I engage my rotary cutter (LP RCR1860 w/ slip clutch - not a light weight machine) at 1400-1500 engine RPMs, and it spins without any theatrics, just a little vibration). I then can raise PTO RPMs to 540 in a smooth constant motion, and at 540 PTO RPMs the cutter is virtually vibration free. If I try to engage the cutter at low engine idle, it will stall the tractor.

On the other hand, my finish mower is smooth and quiet engaging/running at any speed.