TC30 Starting Problem

[tmeric7]

The recommended NAP replacement is KS6600, which I and others have used. Here is a link to a useful thread:

For those with Starting Problem

Great post! I think you may have saved me a lot of work and frustration. I think NH needs to address their electrical problems, other than that they are great little tractors.

www.tractorbynet.com

And a pic of mine installed:

 

[jn9230]

If your ignition switch has a connector labeled as any in the attached it may help for testing. NAPA sells a much more beefy switch. I replaced my TC33D OEM switch which had melted with a NAPA and have not had any problem since 15+ years now.

I again suspect the key switch is faulty and not providing power to the glo-plugs. I know for sure that it does not supply power to the (+) terminal of the fuel solenoid (I checked with a VOM).

And, when I turn the key switch to Run or Start, there is no "clicking" sound from the fuel solenoid. So I tested the fuel solenoid by applying 12v directly to the (+) terminal, and it does "click" so it should be working. The body of the solenoid is ground (-).

The key switch also does not energize the starter solenoid. I checked that it is good, and the starter itself by jumper-ing the solenoid with 12v. When I do this, the starter engages and the engine turns over just fine. Thus, the battery, starter and starter solenoid is good.

The key switch is just like the diagram you posted for the TC30 (figure 3-15), thank you for that.

But the TC30 key switch has 5 posts on back, and the NAPA key switch KS6600 only has four, so I'm not sure if it will work or exactly how to wire it.

I am ready to throw money at a new key switch, but if the NAPA KS6600 is not the correct part, where would I get a new (non-NH) switch? I'm also concerned that the NAPA switch will not fit correctly in the hole where the OEM switch goes. Thoughts? (and thank you all again!)

 

[tmeric7]

Looking at that diagram... there are actually only 4 terminals going to the tractor. Two terminals are connected together (ACC and RUN) See the table to the left. So the NAPA switch would work if you use the ACC position on the NAPA switch for your glow plugs.

 

[jn9230]

I replaced the key switch with new. Still no glo-plug light comes on, and fuel solenoid does not click. Have previously checked the solenoid, and it is good.

Have checked and rechecked all 4 safety switches, still no start, no glo-plug light and no fuel solenoid click.

Starter, (+) cable and starter solenoid known good. Have checked it by jumpering, and engine will turn-over just fine.

I'm pretty baffled right now, thinking maybe biting the bullet and paying NH their extortion price for a new safety module. Anyone know of a cross-reference?

Thanks.

 

[hilltopper34w]

Thanks for your post. I am not married to factory OEM wiring/components. Safety switches are easy to bypass when necessary, so I don't mind keeping them in place. I prefer simplicity, and seriously suspect the electronic safety controller.

In many cases, I tend to blame a loose nut behind the design desk.

 

[oldestgoat]

Theres a well known issue that if you can get it to start by jumping the starter with ignition on that the safety circuits are not allowing enough juice to activate starter. Repair is to add another relay at the starter to a direct line from battery. Did this early on with my TC33da and never had to deal with it again.

 

[jn9230]

Theres a well known issue that if you can get it to start by jumping the starter with ignition on that the safety circuits are not allowing enough juice to activate starter. Repair is to add another relay at the starter to a direct line from battery. Did this early on with my TC33da and never had to deal with it again.

I did this modification, and unfortunately it did not solve the problem.