TC29DA won't start

Raspy · Jul 17, 2010

My tractor has been completely reliable. I shut it off this morning and came back this afternoon to move it and it would not start.

The starter will not run. The battery is fully charged. The transmission levers are both in neutral and the seat safety has been bypassed for a couple of years.

So I looked at all the safeties on the transmission. Everything looks fine. I jumped all of them and still no cranking.

When I turn the key to start I can hear the start relay click, so I switched the relays around to find a bad one. No luck. The starter solenoid wire is dead even with the key to start and the small relay clicking.

So I jumped the starter directly from the solenoid wire connection to the main power wire at the starter and the engine cranks just fine, but no start even with the key on. So I jumped the fuel shutoff solenoid and bypassed it's relay. Then I jumped the starter again and it starts immediately and runs fine.

I'm stumped. It doesn't appear to be a bad relay or a bad safety switch, but it acts like a safety switch problem. The only safeties I can find are the two transmission safeties (manual trans) and the seat safety. The key switch works to turn on the gauges and energize the relays, but no power to the fuel shutoff solenoid or the starter solenoid.

Sheesh, what's wrong?

brin · Jul 17, 2010

You never mentioned the PTO Lever....is it disengaged ?

Army grunt · Jul 17, 2010

"seat shut off" there's a family in Morris ct. that lost a great guy 2 years ago. sadly if there were a seat shut off he would still be here. the safety gods are trying to tell you something.
check all grounds, does it sit out in the weather?trace an clean all plug inns.you'll find a dirty connector.
Army grunt

dqdave1 · Jul 17, 2010

If you had it around tall weeds; check wire connectors on left side under PTO levers towards bottom of tractor. There are a couple of connectors that can be pulled loose. Do you have dash lights? Check main fuse located by starter if no lights. Recheck your bypass to make sure it is stil bypassed. Wiggle all levers in case a switch got out of adjustment.

Raspy · Jul 17, 2010

My PTO lever is disengaged and I can't find any safety switch associated with it. Maybe there is one, but I haven't seen it. Just one for the range and one for the gear selector. Maybe, obviously, I'm missing something. I've had this tractor for about six years and once had the plugs underneath pulled out by a branch. Lately, it's just been running around the place here moving steel parts and lumber as a forklift, or carrying tools and concrete bags in the bucket. Yesterday, I simply parked it in the middle of the driveway for a couple of hours.

The transmission safety plugs on the transmission left side underneath were checked and look fine. Two screwed in switches with two wires each. I jumped them and disconnected them, for the test, and it made no difference.

The seat safety has been bypassed for years and I re-checked it by unplugging and re-plugging and pressing the switch.

The tractor has been stored outside some. But, it's very dry here and I see no corrosion. Just dust.

The main 40 amp fuse is fine and I do have lights. Battery is charged.

I have pulled both side covers below the steering wheel and switched the relays. When the key is turned the starter relay clicks.

Finally, I jumped the fuel shutoff solenoid and jumped the starter. Cranks and runs just fine. Just won't start with the key.

It acts just like there is a safety switch open. It must be something "simple" but, so far I'm stumped. :laughing:

Thanks for all the thoughtful replies. Keep 'em coming

Army Grunt, I know it's not as safe to disconnect the seat safety. But it is so annoying to stand up to see something and have the tractor die. I am the only one running it and I do a lot of scraping, forlifting, gravel, and backhoe work with it. Mainly on level ground. I'm constantly getting on and off of it as I move stuff around.

barbqranch · Jul 17, 2010

I would get a volt meter or voltage tester lamp and touch it to both sides of each switch. It is possible that one of the connectors that goes to the switch is corroded internally and not making contact. My TC29D has a PTO switch somewhere, and yours most likely does also. Perhaps the parts breakdown on NH's website can help pinpoint where the switches are and how many there are.

jinman · Jul 17, 2010

John, do you have an Owner's Manual? The electrical schematic in the Owner's Manual is very handy for troubleshooting starting issues. Also, did you say that you checked all fuses? If relay contacts are dirty, you can often hear the relay coil energize, but the contact being dirty prevents conduction; rare, but it does happen. Also, don't you have a light on the instrument panel that illuminates when the PTO is engaged? If that light is On, it normally indicates the PTO saftey switch is malfunctioning or there is a blown fuse in the operator safety circuit. Just random thoughts...I don't have a tractor like yours, but in some ways mine is very similar.

Raspy · Jul 17, 2010

I haven't had a chance to look into it more today and my owners manual is 200 miles away. So, I'll look there when I get a chance.

The tractor lives at my place in Nevada and I also spend (too much) time in CA working.

The relays don't seem to be the problem because they click when the key is turned and dirty contacts are not the problem because I switched their positions and got the same result. I do think the problem is in the safety circuit, just can't pin point it until further study and testing.

So, thanks again for the responses and I'll be studying the wiring diagram on Sunday. Meanwhile the tractor is down and apart.

It's amazing how much I use it and think nothing of just hopping on and going. My Hew Holland and my Skytrak have done wonders at my place with the new house and all the associated work.

Raspy · Jul 31, 2010

Well, I got it. And boy, do I feel like a pro :laughing:

Turns out it was a blown 10 amp fuse in the firewall fuse panel. All this after I had the poor thing torn apart with both side panels off, the safety switches all jumped and had jumped the starter and the fuel solenoid.

That fuse only controls voltage in the safety circuit and not anywhere else or in the relays associated with starting as the relays still clicked.

Back to normal. :ashamed: