I can't get power to heat glow plugs. If I hook plugs directly to battery, they heat fine. No fusible links. Pulled the wiring harness and have continuity through each wire. I have replaced ignition switch, glow plugs indicator, voltage regulator, oil pressure switch and starter. No good. Tried a new wire to the glow plugs through the ignition switch and still no power. I am stumped. We don't have anybody doing auto electric in our area anymore, so it's up to me.
B5100 electrical issue
- Thread starter SnK
- Start date
Ok, so according to the manual, the smaller red wire from the starter to the ignition should always be hot. it is not. Put my digital meter to check for voltage at the starter bolt for the smaller wire and no current. Current at the bigger one, and when arcing over the two it attempts to start. What gives? It is a new starter...
Russell King
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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Okay I am no electrical expert but it should be a straight forward circuit.
Battery positive terminal is connected to the starter solenoid large terminal. The other side of the solenoid is then connected to the starter. That side will not have voltage until the solenoid is activated. The battery cable will carry the voltage and current to the solenoid. Where the battery cable is attached should have 12 volts to the negative battery terminal when tested (assuming the battery is at 12 volts). If the battery negative terminal is connected to the frame of the tractor then the voltage can be measured between the solenoid positive connection and the starter attachment bolts or any other metal that is attached to the frame.
The red wire from the starter to key should connect to the same large terminal as the positive battery cable. That wire is really just an extension of the positive battery cable to the key switch. It should be powered at all times the battery is connected completely. The key is then turned to a position that energizes the tractor circuits. If correctly wired then you should measure 12 volts from the red wire at the switch to ground.
Not knowing exactly how the glow plugs are activated on your tractor I can only explain in general terms. The key must be in the run position and the tractor circuits live (the oil pressure light and charge light will be on). There is some switch that activates the glow plugs. There will be a wire from key switch to the glow plug switch that has 12 volts on it in this position. When that switch is turned to activate the glow plugs the 12 volts is sent to the glow plug indicator, and then on to the glow plug buss and then the glow plugs themselves. You should be able to measure a reduced voltage between the glow plug buss and negative battery terminal (or ground).
if you can post pictures of the starter solenoid wiring and the dash showing the switches I can give you more detailed information (or post a wiring diagram).
Battery positive terminal is connected to the starter solenoid large terminal. The other side of the solenoid is then connected to the starter. That side will not have voltage until the solenoid is activated. The battery cable will carry the voltage and current to the solenoid. Where the battery cable is attached should have 12 volts to the negative battery terminal when tested (assuming the battery is at 12 volts). If the battery negative terminal is connected to the frame of the tractor then the voltage can be measured between the solenoid positive connection and the starter attachment bolts or any other metal that is attached to the frame.
The red wire from the starter to key should connect to the same large terminal as the positive battery cable. That wire is really just an extension of the positive battery cable to the key switch. It should be powered at all times the battery is connected completely. The key is then turned to a position that energizes the tractor circuits. If correctly wired then you should measure 12 volts from the red wire at the switch to ground.
Not knowing exactly how the glow plugs are activated on your tractor I can only explain in general terms. The key must be in the run position and the tractor circuits live (the oil pressure light and charge light will be on). There is some switch that activates the glow plugs. There will be a wire from key switch to the glow plug switch that has 12 volts on it in this position. When that switch is turned to activate the glow plugs the 12 volts is sent to the glow plug indicator, and then on to the glow plug buss and then the glow plugs themselves. You should be able to measure a reduced voltage between the glow plug buss and negative battery terminal (or ground).
if you can post pictures of the starter solenoid wiring and the dash showing the switches I can give you more detailed information (or post a wiring diagram).
I am attaching a picture of how my starter is wired. From what I understand you saying is maybe it's wrong? It's what the other was wired as, and would heat glow plugs and turn over. Thanks for responding
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Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
I say it is not correct in that arrangement and should be on the same terminal as the battery cable.
Do you have any power to anything on the tractor (lights, dash lights). Does starter crank the engine.
Try this…remove the small red wire from the solenoid and the get a fused wire (inline fuse for installation of electrical devices in cars). Then hook the red wire directly to the positive battery terminal. Turn on key and you should get some indication that you have power.
I think I would just move it and see if it works then. The fused test above is just safer since the fuse will blow if it is wrong.
Do you have a work shop manual that shows the starter solenoid wiring in more detail or pictures of the old starter wiring before you removed it.
Do you have any power to anything on the tractor (lights, dash lights). Does starter crank the engine.
Try this…remove the small red wire from the solenoid and the get a fused wire (inline fuse for installation of electrical devices in cars). Then hook the red wire directly to the positive battery terminal. Turn on key and you should get some indication that you have power.
I think I would just move it and see if it works then. The fused test above is just safer since the fuse will blow if it is wrong.
Do you have a work shop manual that shows the starter solenoid wiring in more detail or pictures of the old starter wiring before you removed it.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Yes you have the ignition feed wire on the wrong terminal.
It goes on the top terminal, same terminal as the battery cable.
Glow plugs have 2 feeds:
Feed #1 (pre heat, key backwards) routes it from the ignition switch, through the glow plug indicator, then to the glow plugs.
Feed #2 routes from the ignition switch straight to the glow plugs not through the indicator.
It goes on the top terminal, same terminal as the battery cable.
Glow plugs have 2 feeds:
Feed #1 (pre heat, key backwards) routes it from the ignition switch, through the glow plug indicator, then to the glow plugs.
Feed #2 routes from the ignition switch straight to the glow plugs not through the indicator.
Agree with last two comments. . . Starter small red wire needs to be on same post as wire from battery (large red wire).
I created a simplified schematic for my BX (https://www.orangetractortalks.com/...rt-and-engine-stop-systems.63554/#post-638769) - the details will differ but you can hopefully get an understanding of how the start/crank system works and they all tend to be similar.
With the starter correctly wired and that small red wire providing battery voltage to the rest of the systems, then you can resume looking at your heaters problem.
I created a simplified schematic for my BX (https://www.orangetractortalks.com/...rt-and-engine-stop-systems.63554/#post-638769) - the details will differ but you can hopefully get an understanding of how the start/crank system works and they all tend to be similar.
With the starter correctly wired and that small red wire providing battery voltage to the rest of the systems, then you can resume looking at your heaters problem.