L2800 Different Safety Switch Question

[Billden]

I have another safety switch question that was not covered elsewhere. If it was, I apologize for not finding it.

When the PTO lever on my L 2800 is disengaged, the bottom portion of the PTO lever closes TWO safety switches allowing the tractor to crank (assuming of course that all of the other safety switches are also closed (ie. HST "neutral", clutch, seat, etc.))

I have been having a problem with both my HST "neutral" safety switch and the TWO safety switches closed by the PTO when the lever is disengaged.
I understand by reading earlier posts that I need to "lube" my HST in order to make sure the foot pedal goes back to neutral when my foot is not on it. I have looked for the place to lube on this and cannot find it on the L2800. Any help?

MORE IMPORTANTLY, I am trying to figure out exactly what the TWO switches closed by the PTO lever do. I disconnected the wire clips and just like I suspected, when I "ohm"d out the switches themselves, they were closed when the PTO lever was disengaged. BUT, when I checked the other side of the clips coming from the tractor, I saw on one of the switch clips, 12 volts with respect to ground on each pin. That didn't make any sense because when the switch is closed, you are effectively putting 12 volts on top of 12 volts. On the other clip, both pins have no voltage.
Why are there TWO PTO "safety" switches and what exactly is supposed to be on both of them when open and closed?

 

[85Hokie]

If I understand your question correctly, the two switches might be a operator presence and the other might be for starting, that is just a SWAG.

I am sure you know that there are two types of switches used in the safety police world, those that are normally open and those normally closed, one allows flow, the other kills it!

Lubing the HST pedal should not be hard, on the BX series you have to pull away the mat a bit to reveal the zerk. On your model I am not sure where it is located. But what I would do is tweak the position of the switches if possible to allow them to hit 100% - there is nothing like a safety switch off by 1/16" to drive you crazy! Someone will chime in and tell you more where the zerk is and what the two switches do.

 

[Billden]

85Hokie,
Thanks for the quick reply. When you say "operator presence", that makes me think of a seat safety switch. The TWO switches I am referring to are identical switches that are both closed at the same time when the PTO lever is pulled backwards (disengaged). These two safety switches are mounted together with a screw through the PTO lever mounting bracket. You would almost think that they were electronically connected but they are not. They are two totally separate switches that are closed at the same time when the lever is pulled backwards.
Thanks again for your quick reply.

 

[85Hokie]

Reason I said OP switch, on the BX series, lets say that you want to mount a 3 point wood chipper, and you got it all hooked up ready to go - and then you engage the PTO, as soon as you LEAVE the seat, machine cuts off!!!!! SO - again on the bx, you have to lift the seat up and place it in a position that you cannot sit in, releasing one of the switches that looks for a butt in the seat.

your two switches are gonna have something to do with OP or starting ......somehow!

you KNOW what you can do...... a zip tie or two!

 

[85Hokie]

Not sure if the will help you .....

 

[North Idaho Wolfman]

Like 85Hokie said one is for the start circuit the other is for the run circuit.
They are seperate circuts that work in seperate instances, crossing the two will make things behave badly.

The voltage your seeing is the transient voltage that is coming from the coil of a relay, grounding it makes the coil energize and thus the relay works.

 

[Billden]

Wolfman, Thanks for your reply. It makes sense that if one of the switches is the start circuit that it won't start if the switch is open (PTO engaged) and once the tractor is running, opening the start circuit by engaging the PTO won't matter anyway. But, how does the run circuit work? It seems like once the tractor is running and you engage the PTO, the run circuit would open and kill the tractor.

Regarding the HST neutral safety switch, according to my Kubota dealer, there is no lube fitting on the L2800 and I just need to spray some WD40 on the post that slides in and out. Does that make sense?

 

[North Idaho Wolfman]

how does the run circuit work? It seems like once the tractor is running and you engage the PTO, the run circuit would open and kill the tractor.

It interacts with the seat switch, second one that when the seat is flipped forward will allow the tractor to stay running for uses like, Backhoe operations (PTO powered pump).

 

[Greenhead]

Wolfman & 85 Hokie are correct. One PTO safety switch link is for starting, and one is for Operator Presence (OP). It happens to me often. When I'm tilling I might see a rock or debris in the dirt, I stop and jump off to move it. If I don't shut the PTO off before I leave the seat the motor shuts down. The tractor is safer the me... Pics are from Operator Book from L4400

 

[Billden]

Thanks for the reply. I have all of the safety switches working again. I am still having a little problem with the PTO cable trying to "kink" up when I disengage it instead of going back in smoothly. I'll check around the forum to see if I can find anything.

Thanks again.

 

[85Hokie]

Thanks for the reply. I have all of the safety switches working again. I am still having a little problem with the PTO cable trying to "kink" up when I disengage it instead of going back in smoothly. I'll check around the forum to see if I can find anything.

Thanks again.

The cable - can it be routed in such a way that cable ties/ zip ties will keep it from kinking?