LB75 won't start???

Hey All,

My 2000 LB75 was slow starting so I replaced the battery back in April. It started fine the few times I used it. I parked it and then when I went to use it recently, it would just click at the starter. I charged the battery, same thing. Replaced the starter, same thing. Tested the battery and starter, same thing. Took apart the ignition switch, same thing. Did a load test on the battery when the key is turned, same thing. Just clicking. I did clean all the connections including the ground strap on the firewall. Checked the continuity of the positive lead to the starter which was good. (I have replaced that cable in the past) I'm at a loss.

Anyone have any ideas?

Check for good power on the starter pos to ground while trying to crank. worked on a bunch and the cables would corrode internally and not start. Could also try jumper cables to the pos and neg on the starter to check cables

Do the cables heat up if you hold the switch in the start position ?
This is when a clamp-on amp-meter is nice to have. You could see what the current draw is on the positive cable.

Pulled the positive lead off and used the jumper cable (pain to get in in past the frame) and left the negative lead connected and jumped the negative to the starter body and it cranked albeit slowly. Battery side got pretty hot on the positive. Reconnected the positive lead and left the negative jumper. Back to clicking.

I'm assuming it's the cable again?

Probably the cable.
What gauge battery cables are you using ?
Ground strap on the firewall.
Not my choice. A negative cable direct from the negative battery terminal to one of the starting motor bolts.
Don't rule out that the replacement starter could be defective.

Is this what you have? The negative lockout switch has been the source of resistance on other members machines.


Here is one of many videos on YouTube that shows how to perform a voltage drop test. This is a great way to test your system!

Swetz,

Thanks for that video. Definitely helped. I tested a bunch (my brother helped hold the leads as he was here painting doors for me). Battery was at 12.6 volts. No appreciable difference in any of the connections. When the key was turned, the ground side between the battery and the starter body was at 7 and change. Back tracked it to the negative lead from the battery to the disconnect switch. It was hot at the battery end. Ran to NAPA and had them make me a new one in 2 gauge. Replaced it but still clicking. Checked it again all the way to the starter and it was showing only a few millivolt drop.

Switched over to the positive side and now I have a 7 and change drop from the positive battery terminal to the positive terminal on the starter and the battery side of the cable is now hot. I think I'm going in circles...

Keep the battery unhooked until you find the problem. We had a New Holland burn last fall

@SL Construction You need to replace the positive cable. The reason you don't measure a problem when the system is not cranking is because you are measuring voltage across an open circuit. By measuring voltage drop (which has to be in an operating circuit) you are able to find small resistances that an ohm meter may have you thinking is ok.

Ohms law is what comes into play. Volts=Amps x Ohms

A starter circuit can draw 4-500 amps easily. So a 12.6 volt circuit drawing 500 amps means you have .014 ohms of resistance. So as you can see a tiny resistance that you can't pick up on a meter, can cause a major drop. This is why voltage drop is used to diagnose high amperage circuits.

I fought sluggish starting on my 575E for a few years. I had new cables made and eliminated the negative disconnect since I didn't use it. Fires right up every time now.

I don't think the disconnect was contributing to the problem but I wasn't using it so out it came.

Hey All,

Thanks for the help. I ended up replacing the positive cable this morning and she fired up. Hopefully that ends this saga and I can continue trying to figure out what's up with the 4wd electrics.

Thanks again!

SL Construction said:

Hey All,

Thanks for the help. I ended up replacing the positive cable this morning and she fired up. Hopefully that ends this saga and I can continue trying to figure out what's up with the 4wd electrics.

Thanks again!

Click to expand...

Not sure how it compares to my 575E but you might find a thread I did on my 4wd of interest. I will see if I have it saved when I get home.

SL Construction said:

Hey All,

I can continue trying to figure out what's up with the 4wd electrics.

Thanks again!

Click to expand...

Not sure if this will help or not. https://www.heavyequipmentforums.com/threads/new-holland-4wd-solenoid-coil.71967/