Electrical issue with Exmark

[tommyrosen]

Hello,
When I tried to start the mower, the key didn’t give any response—no clicks or anything. After disconnecting the battery cable, I started investigating. I opened the cover where the switches are located and found that the ignition switch had a melted terminal that was shorting against another terminal.

According to the diagram, the melted terminal was on terminal A and was making contact with terminal B. I tested the switch and noticed that it struggles to achieve continuity on terminal B and has intermittent continuity on terminal A.

I'm unsure what initially caused the short or what else I should check. Could years of vibration have worn through the plastic protectors, allowing the spades to make contact? I also know the previous owner bypassed the seat switch with a jumper. Any help would be appreciated!

Lazer Z HP Model #: LHP4417KA Serial #: 378958

 

[Tiger Small Engine]

Hello,
When I tried to start the mower, the key didn’t give any response—no clicks or anything. After disconnecting the battery cable, I started investigating. I opened the cover where the switches are located and found that the ignition switch had a melted terminal that was shorting against another terminal.

According to the diagram, the melted terminal was on terminal A and was making contact with terminal B. I tested the switch and noticed that it struggles to achieve continuity on terminal B and has intermittent continuity on terminal A.

I'm unsure what initially caused the short or what else I should check. Could years of vibration have worn through the plastic protectors, allowing the spades to make contact? I also know the previous owner bypassed the seat switch with a jumper. Any help would be appreciated!

Lazer Z HP Model #: LHP4417KA Serial #: 378958

Check all wiring for chaffing or chewing (from mice). Make sure your ground is clean and tight. Install a new correct ignition switch. Before doing all that, check fuses first.

 

[StarTech]

The terminals are the ignition switch are F56 ones. That type wire terminals used at the ignition are bad becoming loose due to the fail of spring contact hinge. When they become loose the constant make/break connection overheats, melt the connector housing leading to leads shorting. Also the switch terminal themselves will overheat from the arcing leading loose or other damage to switch itself.

The current two terminal mention is the voltage regulator to battery connect and both leads are fused. Since neither fuse is blown I lean toward the loose terminals theory. Repair the damage connector, terminals, and switch then test for shorts as this may have destroyed the voltage regulator and stator.

Wire terminals are Packard F56 > Delphi (GM) versions.

 

[slomo]

Pull the negative battery cable first.

Repair shorted wires, anything touching something it shouldn't. Marine grade heat shrink comes to mind. Some Tesa Tape would be good.

I would install a new OEM switch. Yours might be over amps from being shorted.

Connect the negative and test.

 

[John1942]

I really enjoy the learning I receive from this site. Being 83, I have lived through many years of push mowers, sending everything to repair shops when needed, never really fixing anything. After finding this site and seeing all the experience of small motor repairs moving along. The knowledge and experience found here is a delight to read every day. I even replaced a carburetor on my snow blower and for me was an accomplishment! Thanks to all. God Bless.

 

[SamB]

I really enjoy the learning I receive from this site. Being 83, I have lived through many years of push mowers, sending everything to repair shops when needed, never really fixing anything. After finding this site and seeing all the experience of small motor repairs moving along. The knowledge and experience found here is a delight to read every day. I even replaced a carburetor on my snow blower and for me was an accomplishment! Thanks to all. God Bless.

There is a wealth of knowledge here that no single shop can equal. When you seek answers here, you will get real answers. Be polite and good help will be yours. This site/forum has helped me numerous times. I love this place!

 

[tommyrosen]

The terminals are the ignition switch are F56 ones. That type wire terminals used at the ignition are bad becoming loose due to the fail of spring contact hinge. When they become loose the constant make/break connection overheats, melt the connector housing leading to leads shorting. Also the switch terminal themselves will overheat from the arcing leading loose or other damage to switch itself.



The current two terminal mention is the voltage regulator to battery connect and both leads are fused. Since neither fuse is blown I lean toward the loose terminals theory. Repair the damage connector, terminals, geometry dash 3d, and switch then test for shorts as this may have destroyed the voltage regulator and stator.


Wire terminals are Packard F56 > Delphi (GM) versions.

Thanks for your suggestion. I got it.

 

[Born2Mow]

A second layer of heat shrink over those closely packed spade connectors wouldn't hurt, and cost only pennies.