Used B21 1991, 410 hrs. Ya'll probably won't believe this but 1 wk ago, this tractor started and shut off 2x's by it's self; no key in ignition. On 2nd crank up the fuel shut off solenoid smoked and melted the plastic at the end of solenoid. Got new solenoid put on but will only run for 2-3 seconds only. Do not hear the solenoid engage but it will engage with testing. During the 2-3 sec. voltage to the yellow wire jumps to around 10volts then drops to 0 and tractor dies. Have checked fuses, traced wires to best of knowledge. Can't find what caused this problem. Something has shorted out somewhere. The safety switch has been twisted together to make permanent connection. Tractor was working fine with this connection until now. Only had tractor for 30 days used As Is. Help Please.
B21 suddenly will not crank. HELP PLEASE
- Thread starter ronvic1978
- Start date
North Idaho Wolfman
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Simple, you have a major hot wire short in the wiring or a component.
It's probably in the dash around the switch.
Get the WSM for the wiring schematic and go through all the wiring.
It's probably in the dash around the switch.
Get the WSM for the wiring schematic and go through all the wiring.
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I agree with wolfman. Got a bad short on a hot wire some where in the dash. Might be a broken spade in one of the pin connectors. Or could be on the back side of a pin connector under the rubber sleeves. Could actually be moisture or corrosion causing the short also. Gonna have to dig in and do some ghost hunting, possibly an exorcism Hopefully the little beasty won't be to hard to find
I agree with wolfman. Got a bad short on a hot wire some where in the dash. Might be a broken spade in one of the pin connectors. Or could be on the back side of a pin connector under the rubber sleeves. Could actually be moisture or corrosion causing the short also. Gonna have to dig in and do some ghost hunting, possibly an exorcism
Hopefully the little beasty won't be to hard to finddone more checking and cleaning .tractor cranks and runs when key is held in start position when released will die. what now?
This is simple in concept, but time consuming in practice.
There are three basic areas: The key switch, the fuel or key stop solenoid, and the safety circuit.
As already suggested, get a copy of the wiring diagram. Then make a copy so that you can use a highliter on the copy as you follow the connections.
From the key switch battery connection, the "ON" position should put 12V to the connection tieing into the fuel solenoid, via the safety circuit.
Given the symptoms before now, I suggest a very thorough check to verify that the connection paths are good; and, that there are no shorts or sneak paths that should not be there. To do that, will take both the ohmmeter for paths and the voltmeter for operation checks.
Using the diagram and marking it will prevent tail-chasing.
There are three basic areas: The key switch, the fuel or key stop solenoid, and the safety circuit.
As already suggested, get a copy of the wiring diagram. Then make a copy so that you can use a highliter on the copy as you follow the connections.
From the key switch battery connection, the "ON" position should put 12V to the connection tieing into the fuel solenoid, via the safety circuit.
Given the symptoms before now, I suggest a very thorough check to verify that the connection paths are good; and, that there are no shorts or sneak paths that should not be there. To do that, will take both the ohmmeter for paths and the voltmeter for operation checks.
Using the diagram and marking it will prevent tail-chasing.
I obtained the wiring diagram for shut off solenoid circuit. I have checked and traced till blue in face. I have voltage at solenoid when key is turned on. But solenoid does not click when turned on. Solenoid works if manually tested with voltage. All safety switches are closed in the circuit. Could it possibly be the starter relay? Or do you think something is burned out in the ignition switch? Good voltage to starter. Fuses are all good. No moisture or corrosion found in any of the connections and have checked all connections that I can find. Can't find any shorted wires. Not too good with these little diesel tractors; so any more suggestions would be appreciated.
If your fuel solenoid has two lugs for positive, then one lug is for pull-in and the other lug for hold.
The return path for current is thru ground. Just as important as positive wiring. Ground path and positive path must be low ohms.
With battery disconnected on positive side, ohm from ground of solenoid to negative battery post. Contact of solenoid to ground must be clean and conductive. Be darn careful that the ohmeter does not become a path for high current.
Voltage does not necessarily mean that current will flow. A high resistance path will not provide enough current to operate a solenoid, for example.
The return path for current is thru ground. Just as important as positive wiring. Ground path and positive path must be low ohms.
With battery disconnected on positive side, ohm from ground of solenoid to negative battery post. Contact of solenoid to ground must be clean and conductive. Be darn careful that the ohmeter does not become a path for high current.
Voltage does not necessarily mean that current will flow. A high resistance path will not provide enough current to operate a solenoid, for example.
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I would check the 50 amp slow blow fuse. It may appear ok but might be partially blown. Ten volts seems a little low.
If not that, the main switch contacts may be at fault.
If none of those, check the wire insulation, if the plastic melted on the solenoid, a lot of current was flowing somewhere and the insulation may have heated.
My money's on the fuse though.
If not that, the main switch contacts may be at fault.
If none of those, check the wire insulation, if the plastic melted on the solenoid, a lot of current was flowing somewhere and the insulation may have heated.
My money's on the fuse though.
Troutsqueezer: the main switch contacts -- not sure what you are referring to? Where are they? Might be something I've already checked.
The main switch is where you put the key in and turn. Looking at the schematic, there's not a lot of things it can be. Sometimes the most obvious is the culprit.
going to try a few more things today,check grounds ,continuity.
where is best place to order a ign switch?
thanks guys for your input. will let know what happens. probably will order ign switch tonight if someone has good site to order from.
where is best place to order a ign switch?
thanks guys for your input. will let know what happens. probably will order ign switch tonight if someone has good site to order from.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more