TO-30 problem..

cgwarrant

New User
Okay, so I got the new starter switch today. It did the same thing as the other, clicks but does not spin the starter, which tested okay on the bench. However, I have located the smoke I had before, which is the temperature sending wire, which smokes out when I turn the key or when I jump from the battery right to the starter. I know I have to replace that, but is that causing some sort of interrupt in the ignition switch or starter switch that it would cause it not turn it over? Doesn't seem to be connected to the system anywhere. By the way, when I jump from the battery right to the starter, it does not engage. Just sparks and sits there, even though it did work on the bench.

The tractor was converted to 12v before I got it. Has an alternator, 12v battery and a 12v coil. However, there is still a resistor in the coil circuit from the ignition switch, which seems to be weird to me. I couldn't tell if the starter switch was 6v or 12v- it doesn't say anywhere. It ran fine before getting it stuck. The starter appears to be original, which would also seem weird since the rest of the system is 12v. I could not find a voltage regulator anywhere in the system, at least not what I could see. That also seems strange.

Any ideas? The crank/flywheel spin just fine, it seems, so i'm pretty certain the problem is not mechanical. Looking at the wiring diagram for 12v systems and 6v systems is not giving me any clues.
 
The temperature sending "wire" on these old machines is USUALLY a capillary tube that holds a liquid thate expands and drives the gauge. It"s not electrical. If it"s smoking you have an electrical wire shorting out against it

Have you made sure that your battery ground connection on the back of the dash is not corroded or loose? That would explain why you can"t juump it with just a jumper from the battery. If you hold a jumper from the ground side of the battery to the starter flange and then jump from the battery hot lead to the starter lug, I"ll bet it will turn over.
Do you have a good contact between starter flange and the block?(No paint or rust.)Are the battery cables the proper size and not internally corroded? have you tried adjusting the ignitio switch/ You can move it fore and aft to make sure the circuit is closing.
If you have a reistor in the primary ignition circuit with a 12V conversion, who ever did the conversion added the resistor because the original 6V coil needs current reduction when operated in 12v circuit. So if that coil is a6V (~1.6 ohm coil) that resistor should be there.
 
I'll give the ground wire and the ignition switch a shot. The temp sending unit is definitely a wire, not a mechanical unit/tube. The coil says 12v right on it, so I think that the PO just didn't remove the resistor. I'm going to try the jump you recommended. Starter is grounded good. At least it looked like it when I took it off, and it ran fine before the issues. Cables are appropriate, and it is sending current to the starter switch, which is an upgraded 12v model. I'll figure this thing out eventually, with this boards help for sure! This thing is just not that complicated, but when something runs fine and just quits, it throws ya. If worse comes to worse, I'll rewire it. Not that much wire in the system, and the PO didn't actually do a clean job- redneck engineered at best! But, it was working...
 
Have you tried to put a wire from the coil(+) to the positive post and use jumper cables from your truck? Ground cable from truck to a good ground on tractor, then use positive cable from truck to the starter post. Be sure tractor is in neutral. If there is not any thing wrong with distributor, it will run.If it doesn't run look at your points or coil. After this you can look at wire etc.
 
Miner, I'll give those a shot. Jerry, I jumped it as you suggested, and the starter spun it. But it REALLY smoked that temp sending unit wire! Does it sound like the main ground is bad? I did find where the ground to the temp guage had broken from the battery, and that explains why that circuit was having issues. At this point I'm going to rewire the temp guage and take that resistor out of the coil circuit. I'll check the rest of the wires at that time and see where it gets me. I'm going to put the old starter switch back in as well as that does not seem to be the problem. Hope to do it tomorrow, but with weather moving in I probably won't get to it until Tuesday.
 
Most 12 volt alternators have internal voltage regulators, making the external version unnecessary. Easy test to see if you have a good ground is hook ohmeter from ground side of battery to starter base or bolt where starter is attached to bell housing and you should have almost no resistance. If you get a reading like .05 or some such, that's ok. I'm assuming you have a multimeter, cheap ones work ok, and just set it on the ohms setting and run that test. A solution, if that is the problem, is get a long and very heavy cable and run it from the ground side of the battery directly to the bolt holding the starter to the bell housing.
 
You need to check your battery GRONUD take a jumper cable from the neg post to a ground
see if it works Good Luck
 
Either that ground is bad or your cables are bad or the switch is bad OR needs adjusting. Slide the switch backward and see if that helps and then try sliding it full forward to see it that helps. Your problem is in the starter connections from the battery to the starter and you proved that by jumping it via an independent set of jumpers and having the starter turn over. Now you have to find the root cause. The only components are your cables, the switch, and the ground connections, assuming the battery connections are clean.The cround connection at the dash must be good AND the groud connection of the starter case against the engine block must be good fo the circuit to be closed. Don"t gibe up on the switch. I had a problem that required a switch adjustment.
 
I"ll throw my 2 cents in here. The reason you smoked the temp wire is because that pesky electricity was looking for ground any where it could find it. That capillary tube is metal and connected to the engine block. Your starter is connected to the engine block. Just not getting a good ground. Me? I would yard off the starter, clean any and all parts connecting to the block, wipe them down with a fine coat of oil and reassemble. Oil to keep away rust in the future. Grab a chunk of cardboard (overspary shield)and rattle can some paint on it if needed.
Cleaning metal also includes the engine block.
 
Okay. I'm definitely checking the ground. Hard to believe that's a capillary, I could swear it was wire, and the PO has that thing bundled up and zip tied to the point that a liquid could barely flow. It's gotta be kinked. Anyway, I had the starter off and it all looked pretty clean, but I could take it off again and clean it. Step one is battery is coming out, I'm running new ground wires to the guages and taking out some of the rigged wiring to lights, etc. While in there I'll take off the main ground and clean it. Getting rid of that resistor in the coil circuit.

I really don't get the comments on the starter switch. The stock switch is not being used. It was swapped for a ford-type remote solenoid during the 12v conversion. Are the comments pertaining to the original switch? I don't know of any way to adjust the Ford switch.
 
You should check the whole of the wiring as it seems like a lash-up. Fit a new longer ground lead from battery to one of the bolts close to starter. If you want wiring diagram just ask, but say how may wires are on your Alternator (1 or 2) email if you need it...john(UK)[email protected]
 
The only thing i can possibly say is switch the + and - as that will cause sparks and no turning over.Or your starter is arcing to ground when installed and not when on the bench?
 
I was referring to the OEM starter circuit not some sort of farmerized solenoid operated starter ciruit. I flunked Mindreading 101!

Don"t get rid of the resistor unless you are sure you have a real 12v coil(3.2 ohms primary resistance in the coil). If your coil resistance is ~1.6 ohms, you"ll need the resistor with a 12v system.
 
Sorry, I thought I had mentioned that it had an aftermarket starter switch. I was wondering... then I found some photos of oem system and the light bulb was lit. So, the proper term is "farmerized"? That's funny!

Anyway, thanks for the pointer on the coil. All the specs are clearly written on it, so I'll check it for 3.2 before I pull out the resistor. Primary task right now is removing the battery to access the rear of the dash and going over the grounds. I already know I need to re-do the gauges and I suspect I will have to renew the main grounding strap. Then it's on to the rest. Probably work on it some tomorrow.
 
Success! I'm a farmer!

Took out the battery, cleaned the terminals, rewired all the "farmerized" guage grounds and it fired right up! Time to take out the replacement starter switch and return to TSC for a refund! I am so happy!

Thanx to everyone for the help! By the way, the coil is stamped with "for use with external resistor" so it stayed.

I am so happy! You guys are awesome and I am but a pleeb.
 

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