Will someone take voltage readings on X540?

[Venturabass]

I'm struggling to find whether I have an overcharge issue on my John Deere X540. Would someone mind taking the following voltage measurements with a multimeter?

Engine off (I'm measuring 12.58V)
Engine running at idle, no accessories on (I'm measuring 15.3-15.5V)
Engine running full throttle, no accessories on (I'm measuring 15.3-15.5V)

My original post with the issue is here:
http://www.tractorbynet.com/forums/...781-john-deere-x540-overcharging-battery.html

 

[Gator6x4]

How to Test a Lawn Mower Charging System | eHow

 

[LD1]

While I dont own an X540, I have owned and worked on several small-engines over the years.

From kawasaki's ranging from 13-25HP, Kohlers, up to the 27HP in my ZTR, B&S up to 18HP, etc.

A proper charging system always shows around 15 volts. Sometimes a little more, sometimes a little less.

After reading your other thread, I think you are trying to make an issue, where there is none.

 

[Ford850]

You replaced the VR with a new one, and it's also producing 15.3V? It sounds like you've proven there is no problem.

 

[Venturabass]

You replaced the VR with a new one, and it's also producing 15.3V? It sounds like you've proven there is no problem.

That's what I'm starting to think for certain, that there really isn't any problem at all. I wish I knew more about these charging systems.

I happen to stumble upon all this by accident, and when I looked up the proper voltage in the John Deere Service manual, it said if the regulated voltage isn't between 13.2 and 14.7 volts, check for loose connections and a bad battery, and then replace the regulator.

I've checked all the connections and I have great continuity between all circuits. The one odd thing is the battery is a Napa autoparts, but its the correct 12V size 51 spec by Deere. When I had it load tested, its rated for 450 CCA but actually put out 572 CCA. The whole thing kind of worried me that I was overcharging and I didn't want some safety issue with the battery bursting. It's a sealed type and looks like it has vents, but it has absolutely no leaking from it.

I think I'm about to give up this witch hunt until a more apparent problem presents itself.

 

[beenthere]

Bass man
I think that is a wise decision.

But maybe wait until after Halloween.. then give it up.

 

[LD1]

CCA is cold cranking amps. Did they test it at 0 degrees?

 

[Venturabass]

CCA is cold cranking amps. Did they test it at 0 degrees?

No, obviously not. I can only assume it has some sort of programmed scale for temperature. When he did the test it asked him to input the rated CA or CCA. We tried both and in both cases it came back saying it was capable of about 100+amps greater than each of those.

 

[LD1]

Is the battery capable of 20% greater performance than advertised???? Possibly.

Is the $10/hr parts counter employee not have a clue what he's doing? Much greater possibility IMO.

Battery is fine, charging system is fine, tractor is fine and runs well. Don't over think it. All is well and be great fun you don't "actually" have a problem

 

[CCWKen]

1. A fully charged 12v battery is not 12v. It should read about 12.6v (+/- @ room temperature) - You're good there. :thumbsup:

2. Most generators and alternators (regulators) are set to charge batteries at 1.5 to 2.5 volts over battery voltage. - You're good there. :thumbsup:

What's more important than charge voltage is charge current (amps). It should be charging higher after starting and taper off when the battery is fully charged. Depending on how sophisticated the regulator is, the voltage could read high but current is near zero. A sure sign of over charging (too much current) is a gassing battery. Even so called "sealed" batteries have vents and gassing will show as droplets around the vent(s). Doesn't sound like you have that problem either. :confused3: