Need A Little Guidance...

She has a 1987 model 650 JD Diesel, 2 cyl. I spoke to her today, and she in on her 5th battery since last summer! She says her alternator light stays on while the tractor is running (mowing is it's only task), and it seems to "eat" batteries. Common sense tells me that her alternator is bad, but I wanna be sure. If I put a voltmeter across the battery posts while the tractor is running, should I see approx. 14 volts, like my old Ford? If not, how do I check out the alternator? (By the way, the alternator is a small, odd looking thing - at least compared to mine)

Another issue she has is the mowing deck. I have finally convinced her to let me use my brush-hog in the woods, and she keep hers in the yard, but her mowing deck is in pretty bad shape. Our local (excuse for a) JD Dealer tells her that the deck for her tractor is no longer available. Is that true? She was ready to purchase a new one, and has the resources to purchase the dealership if she desired, but the dealer said he could not help her. Should I suggest a good Woods finishing mower, or can she really get a new deck?

All guidance is appreciated, as I am Deere illiterate at this point.

Thanks,
Tommy D.

With the fact that the alternator light stays on, regardless of what the mowing deck is doing, I am leaning towards a bad alternator still. I'm going back over today & put the voltmeter to it to see. Would it be possible to slap a 10si Delco on this machine and cure the problem?

As for the deck, are there REALLY no new Deere decks that will fit this model? My other neighbor bought a mowing deck for his 1986 L245 Kubota last summer..... hummmmm mm

Thanks for your help!
Tommy D.