2420D Electrical gremlins. No start.

[qualityhardware]

Good evening. I have a 2420D that has been a stalwart since 2006. In the past few months, it has developed some electrical issues resulting in a no-start.

For over a year, the headlights, horn, and turn signals stopped functioning, but the rest of the tractor functioned flawlessly.

Oil pressure lamp, glow lamp, temp gauge, fuel gauge, coolant level light - all worked. Thermostart and regular start worked fine, until they didn't.

Current behavior is as follows. I will get the thermostart light when I turn the key left, dash instrument lights, step on the clutch safety after the glow lights turn off, turn the ignition to start, hear the starter solenoid click, and everything goes black. After that the whole tractor is dead. No lights, no clicks, no nothing. Dead.

I checked the battery, it was 12.6v and brand new. Set it on a charger overnight and went through this whole process again. Exact same result.

Checked the fuses in the fuse box. 5A, 10A, 10A, 15A glass tubes, all fuses intact.

This caused me to to investigate and I pulled the covers over the starter and dynamo. I found that a wire was touching the outside of the dynamo, and its rotation wore away the insulation to bare wire. I suspect that may be what caused the initial issues with the lights. Who knows. Spliced in new wire and zip-tied it out of the way so no more contact with the dynamo.

Next, I checked all the battery connections, cleaned everything, pulled the battery ground cable from the frame, cleaned it, the hardware, blasted everything with WD-40, and reinstalled the battery ground cable.

Went through the whole startup procedure again and had the exact same result. A solenoid click, then an entirely dead tractor. No lights, no clicks. Anything.

I replaced the dynamo, voltage regulator, and ignition switch. I got one successful start. Then it all went right back into this pattern. I was able to get a successful second start with an engine boost from the charger, but that hasn't worked a second time. When I got the start, I still had no headlights, horn, or turn signals.

Photos of the new dynamo and voltage regulator, as well as the wiring on the old ignition switch.

I am stumped. Thanks for any help / ideas / suggestions.

 

[mrmikey]

I'd say you've got a bad connection somewhere. Engine to frame, ground cable to engine and/or frame etc. You've got enough of a connection for something that doesn't draw a lot of juice. Minute you put something that draws a lot, the connection arcs out.
Are you >>sure<< the battery is good, voltage doesn't mean as much as it's ability to supply the amps. Think of it this way, you could have 8-1.5V penlight batteries hooked together in series and you'd read 12V but it wouldn't turn over an engine. Do a load test on it is the only real way to test it.

 

[Topzide]

Hook a DVM on the battery when you go to crank it over. If it drops below 10.8 volts, battery is the issue.

 

[FleetMan]

My no dtart problem was orroion between a battery post an the cable connection. Cleaning the post and cable connector soved my problem. Check and clean your battery connections if you have not already done so.

 

[qualityhardware]

I'd say you've got a bad connection somewhere. Engine to frame, ground cable to engine and/or frame etc. You've got enough of a connection for something that doesn't draw a lot of juice. Minute you put something that draws a lot, the connection arcs out.
Are you >>sure<< the battery is good, voltage doesn't mean as much as it's ability to supply the amps. Think of it this way, you could have 8-1.5V penlight batteries hooked together in series and you'd read 12V but it wouldn't turn over an engine. Do a load test on it is the only real way to test it.

Battery is brand spanking new, but yeah, I get it. Something is killing amps.

Thinking I'm going to have to pull the whole cowl and just hunt connections, because something is way off somewhere.

Very much appreciated.

 

[RjCorazza]

Since you've cleaned all of the high amp connections, consider replacing the cables themselves. They have been known to corrode on the inside, which would account for your symptoms.
The actual battery cables are the most susceptible.

 

[ponytug]

Battery is brand spanking new, but yeah, I get it. Something is killing amps.

Thinking I'm going to have to pull the whole cowl and just hunt connections, because something is way off somewhere.

Very much appreciated.

I think that is a good strategy. I tend to start at the battery and do the negative first. I remove, clean, and reinstall each connection. Then the positive to the first landing point. Then I check the voltage from that point to the frame as is, before checking that voltage when the key is turned.

I have been the subject of too many hidden corrosion bugbears, so I use these fishing expeditions as a chance to clean and restore each connection. To @RjCorazza's point above, I have had more than a few wire to terminal connections break, and appear to be 100% ok, as from the outside they look fine, but inside, it is a corroded arc filled mess.

All the best,

Peter

 

[etpm]

Battery is brand spanking new, but yeah, I get it. Something is killing amps.

Thinking I'm going to have to pull the whole cowl and just hunt connections, because something is way off somewhere.

Very much appreciated.

You have a bad connection that is subject to high amperage when starting. The symptoms are typical: turn on ignition, get lights, try to start and it all goes dead. I would make sure the battery cables are not corroded inside. Look at the high amperage circuit(s). Basically the starting circuit. Anyway, that's my opinion. I could be wrong but I doubt it. The fact that you have no headlights is especially notable, being a relatively high amperage draw. And no fuses blown, which points to the fault being before the fuses. Like a bad ground, bad positive connection, or corroded cables. Corroded internally, so you can't see it.
Eric

 

[bmaverick]

Battery is brand spanking new, but yeah, I get it. Something is killing amps.

Thinking I'm going to have to pull the whole cowl and just hunt connections, because something is way off somewhere.

Very much appreciated.

Glass fuses can lie to you. From looks, they are not broken when in fact the can be. Check the fuse for power going thru them.

Have you taken the fuse block off the tractor and cleaned behind it? Don't be shocked how nasty it would get behind there, even corroded contacts.

 

[pycoed]

Since you've cleaned all of the high amp connections, consider replacing the cables themselves. They have been known to corrode on the inside, which would account for your symptoms.
The actual battery cables are the most susceptible.

+1 to this.
I had intermittent starting troubles on my Cushman Turf Truckster with Kubota D950 engine for years. New starter when I got it, new battery & terminals, cleaned earth connections, fitted another earth direct to the starter, still the same, you know the score?
You just never knew when it would fail, so I took to carrying a jump start pack with me everywhere which worked 99% of the time until this spring... Over a mile from home I stopped for 10 minutes & afterwards no start even with the jumper. Walked back & of course it started pouring down with rain, returned on the quad bike to try to tow the Truckster back. It started first time! Something HAD to be done.
Ripped out all the Cushman battery cables & put a new earth teminal & cable on. Wired a new 35sq mm welding lead cable with a new terminal & battery terminal fitted direct from the battery to the starter solenoid. Did the job I should have done years back.
I cut back insulation on the original cables to find corrosion inside the terminal connections & all along the conductor strands - they looked fine from the outside...