TC29D rear transmission safety switch "balk pin" -

[booboo04]

This is part 2 to "it won't start"...but in tracing circuits on my tractor, rI emoved the rear PTO safety switch and the pin fell out. It is rounded on one end and flat on the other. Which way does it go back into the transmission? Two different parts diagrams are of little help, actually have conflicting drawings. However, the switch plunger end itself is rounded. Reading how the balk pin rides in the shift rail, I'd think the rounded end went into the transmission. Anybody know for sure? The shop manual for the 29D doesn't even address it. Thanks to @dlctcg for sharing the TC40D manual's description of what it is and how it works, but alas, NH gives no indication of the orientation...below is a photo for your viewing pleasure.

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[TractorTech]

Balk pins or detent pins ride on the shift rail with the rounded end on the rail. There should also be a spring that goes in on top of it and tension on it is applied by screwing the cap back in.

 

[booboo04]

@TractorTech you're a lifesaver! Logic prevails. So then, one more question. I did check the switch while installed and had continuity. Didn't get the opportunity to check the switch's plunger action in the rush to reinstall it into the transmission case...however, the manual says that it should have continuity with the switch's plunger "in".

Rear PTO Safety Switch Testing
Use an ohmmeter to test the rear PTO safety
switch.
• With the button in the "OUT" position, there
will be no continuity across the terminal
leads.
• With the button in the "IN"position, there will
be continuity across the terminal leads.

Below's a screenshot from the parts diagram. My question is this: are there two shims as shown on the parts listing - #23? The picture is the same as the single gasket, so no help there. Sorry the parts listing link wouldn't work right. Manufactured in May '99

Now check out the TC40D attached file. This switch and rubber gasket is what I believe I have instead of the shim setup. Again, it was a rush to get it back together. I will jack it up and put some stands under the left side to stem the flow.

I know I have to get that pin back in before I can even jump the switch, but I'd like to have everything available.

The two wires from the switch are black, but the two into the harness are orange and green I think. My buddy plugged it back in before I could tell him which was which. Does that matter?

I am open to suggestions! Still have to troubleshoot the "no start" on this tractor after I get this pin back in place. I'll get a new switch and have it ready, and test the old out of the machine. Will need to plug that opening up while I test the switch.

It did start when we jumped across the starter to the solenoid. I have continuity from the starter to the ignition switch but no power.

Thanks for your help!

 

[thclimer]

My best guess is looking at the electrical schematic the rear PTO, Transmission Range and Mid PTO switches are all in series so the orientation of the connector does not matter.

 

[ruffdog]

Yes, it looks like you could ground the entire safety switch circuit at the relay to eliminate the switches as the problem. Unless, it is the relay that is the problem........

 

[TractorTech]

Jumper the two wires to see if it will start without that switch. If so, then the switch is bad or needs adjustment, but you say you don't remember a shim, so probably a bad switch.
The "in" position of the switch means that in the tractor, it is riding on the rail, the "out" means it's in a detent.
Like thclimber said and the schematic shows, all of the switches create the circuit when they are in a closed state.

 

[dlctcg]

@booboo04 - I just want to make sure you are using the correct testing procedure.... You have referenced this as the "Rear PTO Safety Switch Testing" but the switch I referred you to in a pervious post is the Transmission Neutral Safety Switch that is located on the lower side forward the front of the operator platform (part # SBA385201260) & is what is pictured in the diagrams posted above; this is where the PIN (part # SBA324560140) is located... not as part of the Rear PTO Safety Switch which does have a different testing procedure.

Just wanted to make sure you are looking at the correct testing procedures...