Another Dead G1800 Thread

[Snakebit12]

Hi everyone - 1st time poster.

Had an unusual day yesterday with my G1800 (1992).

After 5 hours of mowing, I parked, "turned off" , removed the key and started to walk away until I noticed that the tractor was still running. I re-entered the key, turned right and then back to "off" to see if it would shut down. It did not but I did notice the idiot lights and gauges functioned when I turned the key.

I pushed in on the little plunger on the ESS which shut off the fuel supply and stopped the engine. However, when re-inserting the key...nothing. No gauges, lights, cranking...nothing. My safety switches are bypassed so those should not be the issue.

The battery is fine. I have juice at the starter solenoid and coming into the key ignition switch. I have continuity in the switch between red/red&white when turning the key. I unplugged the distribution box and tested for voltage in all of the slots in the pigtail coming from the wiring harness below the dash. One pin measured 0.20 volts...just barely nudging the needle.

I am not very knowledgeable on these things but 0.20 volts won't run much. Suspicious of the switch as perhaps it has continuity but is not passing full voltage through. I have not figured out how to measure voltage out of the switch other than at the distribution box pigtail.

Something has effectively killed the voltage to the distribution box. This would explain why the ESS wouldn't work and (I think) why everything is dead now. It does not explain why I saw the gauges work when I turned the key before pushing in the ESS plunger yesterday.

I'm sorry to be rambling - this is frustrating (as I'm sure you've experienced before with other electrical issues)

I would appreciate any suggestions.

John

 

[lugbolt]

probably an issue somewhere else in the harness

but combination boxes are known failure points on those tractors, I had to put one on mine before I sold it, and now my dad's needs one. They are rebuildable, but I don't have the patience for fixing electronics, thus it's just as well to replace it with a new one that is more robust (part number is superceded)

these mowers are well known for electrical issues, or were--not too many around anymore, unfortunately. Best conventional riding mower ever made, in my opinion

u need to learn how to properly diagnose electrical circuits under a load. You can find that on youtube

 

[Snakebit12]

The (apparent) solution was the 1st one that I considered...and discounted. A battery can read 12V and still collapse under load.

She roared to life after swapping batteries. Ocham's Razor.

Still a bit glitchy with the electronics...the gauges work but the headlights and dash lights are out. I can live with that if it starts, mows and turns off every week.

From a diagnostics perspective, could I have tried jumping with a smallish (Subaru) car battery before moving onto wiring, fuses, etc?

 

[lugbolt]

yeah u can jump them with booster cables from a 12v battery just don't short the plus cord jumper against the muffler, bad things happen. The muffler is very close to the plus cord terminal

 

[Snakebit12]

Yep - that is a tight fit around the positive terminal.

It has been a great mower for 28 years...hope for many more w/ only 1,300 hrs. I don't think that Kubota builds them like that anymore.

 

[whitetiger]

Yep - that is a tight fit around the positive terminal.

It has been a great mower for 28 years...hope for many more w/ only 1,300 hrs. I don't think that Kubota builds them like that anymore.

T2090 / T2290 are the current versions of the T series mower. They are pretty much the same with cosmetic improvements.

 

[Snakebit12]

My issue with the T-Series is the deck widths...currently have (and need) 54" and the available T choices are 42" and 48".

The GR series offers 54" (along w/ 48") but they are pretty pricey.

Crossing fingers that the G1800 will keep rolling.

 

[Mark_BX25D]

The (apparent) solution was the 1st one that I considered...and discounted. A battery can read 12V and still collapse under load.

She roared to life after swapping batteries. Ocham's Razor.

This is why a test light is a great companion to a meter. Best if you can use a household incandescent bulb - it will put more load than a regular 12v test light.

Still a bit glitchy with the electronics...the gauges work but the headlights and dash lights are out. I can live with that if it starts, mows and turns off every week.

That's probably a fairly simple corroded connection somewhere. Remember your grounds! Lots of weird problems are due to poor grounds. Clean them to shiny metal, slap on some dielectric grease, and you are good to go.

From a diagnostics perspective, could I have tried jumping with a smallish (Subaru) car battery before moving onto wiring, fuses, etc?

Yes. Not a bad idea if you have one handy.

 

[Snakebit12]

That's probably a fairly simple corroded connection somewhere. Remember your grounds! Lots of weird problems are due to poor grounds. Clean them to shiny metal, slap on some dielectric grease, and you are good to go.

The ground wire leading from one of the headlights was shorting. After disconnecting the map assembly, the light would flicker on/off as I jiggled the black wire. Apparently, that short took out the other headlight and the dash lights. It is a bit of a goofy design as the wires are stretched every time you open the hood.

Replaced all of the (28 yo) wires from both assembles, put on new connectors and as someone once said "Let there be light". And there was.

Thanks to all for your comments.