engaging the pto kills the engine

Mlarv

Active member

Equipment
BX23S
Jan 19, 2020
218
176
43
Crossville TN
My B3200 developed a problem yesterday.
When I engage either the mid pto or the rear pto, it kills the engine. Otherwise the tractor runs fine.
Are you engaging the MMM at full PTO speed? If not it will kill the engine. Are you trying to engage a rear implement at full PTO speed that will kill the engine or shear the shear pin or both.
 

Daniel Pullum

New member

Equipment
B3200
Aug 7, 2022
10
0
1
Decatur, Illinois
No and No.
It is mechanical, it doesn't engage the pto until I let out on the clutch. I've always had the rpm at low to medium speed and then slowly let the clutch out to slowly bring the implement up to speed. I had not used the rear PTO until last week to run a bushhog. That worked fine starting and stopping many times. I went out two days ago to mow our yard. Even with the clutch engaged moving the pto levers to engage instantly kills the engine. There is no load on the drive line.
Thanks for the suggestions.
 

RBsingl

Well-known member

Equipment
Kubota F 2690 72" rear discharge deck, Deere 955
Jul 1, 2022
408
425
63
Central IL
Sounds like it is a safety switch not functioning properly i.e. the operator presence switch for the seat.

Rodger
 
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Old_Paint

Well-known member
Lifetime Member

Equipment
LX2610SU, LA535 FEL w/54" bucket, LandPride BB1248, Woodland Mills WC-68
Dec 5, 2020
1,559
1,456
113
AL
Gotta go with @RBsingl. Safety switch somewhere not making up, especially with it shutting down immediately when engaging the levers. Seat switches seem to get a lot of attention in the forums. Hopefully you have an electrical diagram for your machine.
 
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Daniel Pullum

New member

Equipment
B3200
Aug 7, 2022
10
0
1
Decatur, Illinois
Gotta go with @RBsingl. Safety switch somewhere not making up, especially with it shutting down immediately when engaging the levers. Seat switches seem to get a lot of attention in the forums. Hopefully you have an electrical diagram for your machine.
Gotta go with @RBsingl. Safety switch somewhere not making up, especially with it shutting down immediately when engaging the levers. Seat switches seem to get a lot of attention in the forums. Hopefully you have an electrical diagram for your machine.
Hey Old Paint,
Yes, I have the parts kubota book. On the page with the electrical schematic, it shows the safety switches for the mid and rear PTO but it does not identify those by name or part number. I went to Messicks and get the same results. I can't see the switches from above or below. Why doesn't Kubota identify those parts???????
 

Old_Paint

Well-known member
Lifetime Member

Equipment
LX2610SU, LA535 FEL w/54" bucket, LandPride BB1248, Woodland Mills WC-68
Dec 5, 2020
1,559
1,456
113
AL
Hey Old Paint,
Yes, I have the parts kubota book. On the page with the electrical schematic, it shows the safety switches for the mid and rear PTO but it does not identify those by name or part number. I went to Messicks and get the same results. I can't see the switches from above or below. Why doesn't Kubota identify those parts???????
Shoot me a link to the diagram, or scan it and send it. I'll be happy to have a look and mark it up for you. That's why we use this forum, isn't it?
 

Old_Paint

Well-known member
Lifetime Member

Equipment
LX2610SU, LA535 FEL w/54" bucket, LandPride BB1248, Woodland Mills WC-68
Dec 5, 2020
1,559
1,456
113
AL
Shoot me a link to the diagram, or scan it and send it. I'll be happy to have a look and mark it up for you. That's why we use this forum, isn't it?
@TECH101 posted a photo of a page from the WSM that confirms what I figured. The OPC module is basically a relay with several inputs that solves all the logic for engine start/run permissive. I can't quite see all of the diagram that shows all the inputs, though. That's a pretty good description of the OPC's function, but it really doesn't describe all the logic built inside that little smart relay. I would think, though that if the clutch was released and the seat switch were bad, even without the PTO engaged it would kill the tractor, if the problem was just the seat switch and the OPC logic is what I think it should be. I need to know the logic of the OPC, or at least see the full diagram, and perhaps the operator's manual section that describes PTO operation. If this ONLY kills the engine with the PTO shift lever engaged, it's activating (or not) some other logic in the OPC.