TC29D Ignition Switch Replacement

[TC29D]

Hi all , New to this Forum and need a little info. 12" of snow a week ago, another 12" over the weekend and more to come tonight and tomorrow. Dont get me wrong, any reason to play on my tractor is good.
The problem I have is the Ignition Switch. I have read other posts regarding this problem and seems to be common. Seems that as I turn the key I have to look at the Glow Plug indicator light to make sure it is on and adjust the key accordingly. After the light goes out (indicating plugs are heated) I then turn the key all the way and engage the starter. After the engine is running I have to carefully turn the key counterclockwise just a bit otherwise the Glow Plug light stays on (im guessing otherwise the Glow Plugs would keep burning). If I turn the key too far counterclockwise the engine will shut off.
Ive read other posts exclaiming that these ignition switches from NH are crap and an aftermarket replacement should be considered. I really dont want to spend $70 for another switch especially if the new one is going to be crap also. SO can anyone lead me in the right direction as to a suitable replacement? I assume it would have to be a four position switch?
Thanks for your attention. Any help you can offer will be appreciated.

 

[jinman]

It is very hard to be sure if it is the ignition switch or the glow-plug timer on these tractors. About the only way you can check is to monitor the voltage to the timer. What I do know is that if your ignition is failing to put out the proper voltage for your glow plug circuit, you should also lose power to the fuel cutoff solenoid and kill the engine. For this reason, I'm thinking your most likely culprit is the the glow-plug timer. It is conceivable that you could have reduced voltage that would drop out the timer but not drop out the fuel c/o solenoid, but that would have to be proven with a voltmeter. I think I'd try the timer first, but they are not cheap. I just bought one for my tractor and it was over $61.

 

[dqdave1]

You could remove the switch and bench test it to rule it out. Testing it would just mean puttin g a continuity tester between terminals as you move key to see if contacts are working correctly.

To remove switch; remove two bolts at center of lower section below steering wheel; then raise hood and remove two bolts at firewall that hold lower panel in place. Switch will have a connector that can be unplugged for resting. No need to remove switch from panel while testing.

This panel will need to be removed to expose glow plug timer as Jinman related to in his post.

 

[TC29D]

Thanks for the replies. I can feel the switch is messed up as I turn the key. It no longer has a nice and smooth action and the different stops can be felt. Now kinda rough and hard to tell where the different positions are (on, Glow plug, start). Sometimes i have to just go by the indicator lights and the starter to verify switch position.
I am just trying to find out if someone has been suscessful using a different switch instead of ordering an OEM that may end up being another piece of crap. Thanks

 

[thclimer]

I replaced my ignition switch on my TC33D with one from NAPA (see post #4 in the following link for part numbers and pictures). Everything has been working fine since.

http://www.tractorbynet.com/forums/...ing/109372-tc33d-glow-plug-problem-fixed.html

 

[TC29D]

I took the lower cover off the other day to see what kind of connection I was dealing with in order to find an after-market switch. Of course I found that the wiring harness plugs directly into the back of the switch...no pigtail coming from the switch to a plug as I hoped. Seeing this I did hot want to cut the OEM plug off the harness and then deal with which wire goes to what terminal. So...I decided to bite the bullet and order a new OEM switch and hope for the best.
However if this happens again I will not hesitate to cut the harness and go with an after-market. Thanks to all for the Information. I will post when I receive the switch and make the install.

 

[Fork14]

I just got the Napa switch for my TC 34 DA and wanted to find out if the wiring of both red wires to BATT, purple wire to ST and orange wire to IGN will work for me before I cut the wiring harness?

 

[jinman]

I just got the Napa switch for my TC 34 DA and wanted to find out if the wiring of both red wires to BATT, purple wire to ST and orange wire to IGN will work for me before I cut the wiring harness?

That appears to be exactly the way to wire the switch from my diagram. Mine is not the same model tractor as yours, but it has red as input power, orange as power out, and a white wire to the start circuit. Your tractor seems to have a purple wire instead of the white wire mine has.

 

[davcon]

I replaced my ignition switch on my TC33D with one from NAPA (see post #4 in the following link for part numbers and pictures). Everything has been working fine since.

http://www.tractorbynet.com/forums/...ing/109372-tc33d-glow-plug-problem-fixed.html

thclimer,
Thanks for reminding me of the old post. I must have deleted the pics from pb not realizing they drop off here and others may still need them. At any rate I reloaded the pics for the old thread.
http://www.tractorbynet.com/forums/new-holland-owning-operating/88444-those-starting-problem-2.html
Dave

 

[Fork14]

Thanks for the replies, I'll try to get it installed this week.