Potential Electrical Problem (L185DT)

[Rosher18]

Hi all, I'm interested to see your opinions on the measurements I took recently.

A while back I posted something about my charge list staying dimly lit while my tractor was running. I parked it a few nights ago and when I pushed the throttle back to idle to finish cool-down, I noticed that headlights got dimmer and the charging light I believe did so as well. Intrigued, I revved the motor again and the lights got brighter until it hit 1500 rpm, then remained the same brightness.

I pulled my DMM out and measured voltages at the battery in various states. (these are from memory so they may be a bit inaccurate)
Motor and key off: 13 and change volts
Motor off key on: (less than above, but not less than 12V)
Motor idle key on: 14.3V
Motor 1500 Rpm key on: 17.5V

I think the 17V is indicating a regulator issue since the voltage stayed there longer than I'd think it would take to recharge the battery from starting the motor.

What else should I check to verify the problem? I've been running the tractor with the headlights on to protect the battery, because headlights on seems to reduce the voltage by a volt or two.

Thanks all!

Sent from my VS986 using Tapatalk

 

[Jim L.]

Even with the headlights on that battery will fry.

Might check the ground connection and make sure that it is clean so that the regulator has good reference.

Otherwise, time to look for another regulator.

 

[North Idaho Wolfman]

Time to look for another regulator.

I'll follow that up with a, Ditto.

 

[scdeerslayer]

If you're using a cheap meter try a different one, it could be measuring high.

 

[Rosher18]

Thanks for the replies everyone! I was waiting for Tapatalk to give me some notifications of replies, but I had to access the sub-form to find my thread and your responses.

I'll re-check voltages this evening and publish those, then check the ground connection (someone on here likes to say clean, bright, and tight), then start looking for a regulator.

Sent from my VS986 using Tapatalk

 

[SDMauler]

You might have your battery load tested as well. As batteries age, their internal impedance tends to increase (and no, you can't measure it with a VOM- it takes very specialized equipment capable of measuring Milli-ohms, using an AC waveform for testing, and a baseline when the battery was new) which might cause the terminal voltage to be a bit high. You could also try a different battery, even if you have to connect it with jumper cables if it can be done safely. It might start the tractor, but as it is charged, the impedance increases, as does the terminal voltage. It wouldn't hurt to have that regulator checked. I know the old mechanical regulators often benefitted from a tap with a screwdriver handle or a cleaning of the contacts. The newer solid state regulators either work or they don't. Not many of them are adjustable.

 

[Rosher18]

Thanks for the reply, SDMauler. I'll need to take a look into this deeper now that I've fit my tractor into the shop. It's time for the first oil change since we've taken ownership of it, and I'll have a chance to look at the electrics then. I worked it hard for a good 8 hours yesterday, so I figured a dose of Seafoam and then an oil change were a good idea.

Sent from my VS986 using Tapatalk