NH TC45A Starting problems

woolyAcres · Sep 29, 2016

My NH45A wouldn't start last night. I'd been using it off and on all day. Then all the sudden it wouldn't start. I've checked the different safety switches and they seem to be working. The engine cranks, but won't catch. I thought maybe it was low on fuel, had water in the fuel, or had air in the fuel so I cracked the bleed screw on the injector pump. Fuel comes out fine. I then provided 12V to the solenoid on the injector pump, cranked the engine using the key and it fired right up.

So my question is, how do I figure out what's preventing 12V from getting to the injector pump? Seems to me it could be the ignition switch or one of the safety mechanisms preventing power from being delivered to the injector pump. I'm not sure, but it seems like the only safety switch that could prevent it from starting (or stop it running) is the seat switch. I've removed that and shorted the connector so it should always think someone is in the seat. This did not solve it. Does this sound like an ignition switch problem or some other part of the safety system like the 'occupancy sensor module', etc?

I see lots of posts about the TC33 having ignition problems but they mostly seem to be mechanical failures. Mine still feels fine. I have a DMM, but don't know how to test.

Any ideas, suggestions?

Thanks

npalen · Oct 5, 2016

I found that shorting the seat switch on my NH TC29DA didn't work as it would start and run only a few seconds.

woolyAcres · Oct 7, 2016

Sorry to hear that. I cleaned up a bunch of connections, got all the crud out from under the dash and didn't she start right up. Well a day later the problem was back. At the moment I can make her run. I made a small jumper that has a big alligator clip on one end and the other has a blade socket that fits right onto the fuel solenoid. I just have to attach one end to the + battery terminal and then start it with the key. Turn off is a bit trickier. Turn off key, hop off tractor and disconnect jumper wire. Not great but it lets me move it.

WM75Guy · Oct 7, 2016

Make sure you didn't bump a lever. I have had mine not start because I forgot to turn off the PTO or bumped a lever. Also moving them back and forth and then returning them to off can make sure they are getting good contact. Page 2-6 of the manual for my TC40DA says 1) PTO lever off 2) Range lever in neutral and 3) either the driver in the seat or parking brake set. If the driver is not in the seat or the parking brake not set the engine will turn over but not start as the fuel solenoid is not activated.

Hope it is an easy fix.

Bobby22 · Oct 10, 2016

Wooly
I am going through the same problem with my TC33D and I have done a ton to this tractor and nothing seems to be working. I made a jumper to bypass my first relay and I can use the tractor. I did the same jumper from battery to fuel shut off solenoid but did not trust it for to long. I have Tractor Ted helping me figure things out at the moment. I think you are on the right path of it being an safety interlock. My service manual does not cover the actual relay bar I have so I am reaching out for help. http://www.tractorbynet.com/forums/...84027d1475998126-tc33d-wont-start-capture-png. This is the jumper I made for mine and it seems to be working until I can find the actual problem. I have a 3 days weekend coming up so I am going to try to put some more time into. Will let you know if I find anything.
Bobby

woolyAcres · Oct 15, 2016

@Bobby22-

I'll have a look at your thread. Thanks for the link. I haven't fixed mine yet, but my jumper wire that runs from battery terminal to fuel solenoid keeps it usable. Of course, the irony here is failure of the safety features has made this tractor something that's not easy to turn off!

I suspect it's my Operator Station monitor (or whatever it's called that compares all the necessary sensors to decide if it should allow power) to the solenoid. I thought I saw a testing procedure for that here on TBN somewhere but now I can't find it.

Anyway, good luck with your machine. They're great when they run and in ~1000 hours, this is the only problem I've had. So hard to complain too much.

STx · Oct 15, 2016

Based on what you're saying, I don't think it's a safety switch problem, I think there's a break in the fuel solenoid circuit somewhere. Trace that wire back and see if you can find it.

I still have a factory service manual on my website, http://www.texashogtraps.com/nhrepair.zip. If you download, a thanks would be appreciated. I don't want any money for it but, it irritates me when people use it and can't be bothered to say thank you. It took me about 40 hours to get it into a format that could be used on any computer (the CD will only work on Windows XP) and I have absolutely no problem sharing it, I just like to know it was appreciated is all.

woolyAcres · Oct 17, 2016

@Stx-

You know I hadn't thought about a broken wire or circuit problem but it would fit the systems- intermittent, however the tractor has never stalled once running. I'd expect if that circuit were faulty or had a bad wire, when it flaked it would cut power to the solenoid and cause it to stall don't you think?

I haven't checked the link you sent yet, but I'll offer my thanks in advance for putting together the service manual. That sounds like a lot of work to get it all formatted. Much appreciated.

STx · Oct 17, 2016

woolyAcres said:
@Stx-

You know I hadn't thought about a broken wire or circuit problem but it would fit the systems- intermittent, however the tractor has never stalled once running. I'd expect if that circuit were faulty or had a bad wire, when it flaked it would cut power to the solenoid and cause it to stall don't you think?

I haven't checked the link you sent yet, but I'll offer my thanks in advance for putting together the service manual. That sounds like a lot of work to get it all formatted. Much appreciated.

Any intermittent break in the circuit should cause it to fail when it opens. I understood your earlier post to say that you were running a jumper wire to the solenoid though, which would bypass the fault.

woolyAcres · Oct 17, 2016

@STx-

You are correct about the jumper wire so it could be a problem, but prior to having this problem it has never stalled. Still worth checking so thanks for suggesting it.