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Batteries - lead-acid/lead-calcium & voltage

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Just a reminder that battery type and proper voltage from the charging system needs to be matched to maintain a full charge, premature failure, yellowing of teeth, etc.

The Starter/Generator (what I used to refer to as a "starterator") came out when almost certainly, all batteries were lead-acid and needed 12.6 to 12.8 volts to achieve/maintain a full charge and longest life. They could withstand deep-cycling pretty good too.

The newer lead-calcium batteries require something more like 14.3 volts - and don't handle deep cycling worth a darn. Bring them down to 8 volts or less even a few times, and they may not fully recover.

I cannot stress this enough: That 1.5 volts or so difference is critical for lead-calcium battery life.

Folks like me who have a S/G, and use an automotive 51R battery, will need to tweak the regulator to get that higher 14.3 volts.

I did just a little checking, and found that the "DieHard Gold Garden Tractor Battery" is a lead-calcium, so it definitely would benefit from the higher voltage.

I also have two machines with alternator engines - I have no idea what ANY of them put out voltage-wise.


OK, let the Holy Wars begin.:D

Don't know anything about that links owner, other than it seems to give a fairly readable discourse on batteries.

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Excellent points. They same way that some TV remotes or wireless mice wont work with 1.2V rechargeable batteries but work fine on a cheap Alkaline batteries.

Care to share how you "Tweak" a G/G regulator to get 14.3 volts if you need it? I actually have a 51R from Farm & Fleet. I'll have to look it up to see if it is a lead or calcium.

I do plug it into a float charger/maintainer whenever it sits for more than a few days so I haven't noticed any long time problems.

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I knew that question was going to be asked. I haven't doe the GT types - just full-sized equipment - but hey it's a Delco - so they're about the same.

Here's a YouTube lnk:

And a copy of an old Delco-Remy Service Note:


I'm sure the regulars here already have the answer down pat.

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Following in the very large shoes of one of our members who now looks upon us from the heavens, Al Eden would certainly chime in to gently set the record strait on Regulator settings and proposed Generator Amperage of our Starter/Generators. However!! Don't despair! In the tech pubs, Al did a fine job of outlining the parameters on all corners of the charging and regulatory settings for the most commonly used S/Gs and Regulators for our Fine Vintage Iron. Quite a good read and packed with pertinent information in a way that only Al could deliver, so for me to attempt to dictate here in honor of Al would be an effort in futility. So.......do ya a sight wide search! lol

On another note and just to clarify a thing or two, as to avoid mass hysteria among the masses....Our S/Gs must be used in conjunction with a regulator that is designed to regulate much lower amperage than their Automotive counterparts. Forty Amps max, most generally. Buying from a knowledgeable retailer like SandyLakeImp.com, JacksSmallEngines and other "old school" dealers are given their place here on the home page of SimpleTractors and it's for good reason. They know their spit and wont hit your shoes with it. Don't rely on your new Simplicity dealers parts employees who just started shaving three weeks ago. Ask here and you'll now be given sour suggestions.

On this revisited post, it's right up there with many of the important things that members, new and old, should always stay on top of in order to keep our old Iron in service. Ask, and ye shall receive!

Cheers! Zip

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Good to hear from Zippo. There are a lot of serious issues with these old starter generators and voltage regulators. To much juice will cook your battery, possibly cause an explosion and may even ruin your afternoon.

The voltage regulators from cars are generally to heavy for these tractors. Stick with one designed for a tractor, max out at 15 or 20 amps charging total. Maybe the newer tractors (late 70s and up) need more, but the older ones don't.

Bob Tiarks (BLT) had a good thread on installing and adjusting regulators a while back. Be careful, too much voltage will blow out headlamps, fuses, dashbulbs and screw up your Hobbs Meter.

I have found some very old shop manuals on testing, adjusting, and installing regulators. They are sizable files (24MB) but I can get them to you via WeTransfer (a free big file transfer site) if you PM me an email address.

Also, I bought a few trickle chargers from Harbor Freight (about 5 bucks). I keep them on the idle tractors' batteries. This seems to work well in the winter, and is not necessary in the summer.

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