Farmall Cub

OR you could get a Delco alternator modified for 6V system, swap battery post, ammeter connections, and coil connections and be good to go. A lot of A Model guys use that system to have better lighting and stay 6V. Corvette parts work on old Chevy trucks too. Had a Corvette fuel pump on a 53 Chevy pickup. Made the windshield wipers work the way they were supposed to!

Looking at Harold's picture, and from what I can tell on the web, the 10si alternator comes with a pulley for 3/8" belt. The generator belt on Cubs and SA is 1/2". Does the 10si have a split pulley so it will properly fit the 1/2" belt?
Gerry

ibrake4rust wrote:Does the 10si have a split pulley so it will properly fit the 1/2" belt?

No. But the solution is rather simple. Swap pulleys from the generator to the alternator.

Should you ever need to change the internal regulator, it is about 10 bucks and can be done on the tractor in just a few minutes....Another plus...Dave

Eugene wrote:

ibrake4rust wrote:Does the 10si have a split pulley so it will properly fit the 1/2" belt?

No. But the solution is rather simple. Swap pulleys from the generator to the alternator.

you also have 2/3 surface area of the belt to pulley, it does not even have to be real tight. most slippage is do to old belts
Boss

The original late cubs had the same pulley on the alt.

On the original late model Cubs the alternator was rated at 37 or 42 amps, now all the 10si remans are 63 amps, which is not needed. The Hitachi alternators current outputs are closer to the original specs of the charging system.
Looking at the Cub parts manual, the pulley used on the alternators was 1961291, here is a link to the pulley showing it was for 1/2" belt. About simply changing the pulley from the generator to the alternator, IH calls out different part numbers for the two applications, normally the same part would be called out if interchangeable.
I know it's preference, but I'd never go to the trouble and expense of upgrading to an alternator and then accepting that the belt doesn't fit the pulley. And I'm glad to say, neither did IH.
Gerry

My two cubs that I've converted to 12v were originally 6v.....so originality was out. It was merely a convienience conversion. I don't think that an additional 20 amp charging ability over what an original late model cub alternator produced even entered into consideration. IMHO....not going to harm anything. As to the pulley size, with 1800 max RPM and a 21 inch belt...the chances of the belt slipping or pre-mature wearing is minimal. I toyed with the idea of changing out the pulley, and the lathe you see in the background of one of the photos is quite capable of modifying or even making a custom pulley. It's just not needed. Once the hood goes on, nobody know what the pulley size is. In another drift from originality...........I installed a volt meter.

I too like the volt meter in the conversion. If the amp meter is working properly I will typically leave it as is , but if not , a volt meter will provide a better idea of the battery and charging system performance than the amp meter. . IMO

Harold,
the reason I bring up the current capability of the 10si alternator is because if it's not fused a fault like shorted cell or badly discharged battery, it can cause the alternator to supply so much current it can burn wiring or overheat the battery which can lead to catastrophic failure of the battery. The battery group 26, which is what most use in the conversion is not matched to a alternator that can supply continuous 63 amps. So, I recommend a 30-40 amp fuse in the charging wire.
Gerry

Just because it is a 63 amp alt. does not mean that it is putting out 63 amps all the time. All of mine cut back shortly after start up. It is not rocket science! I have group 26 batteries that are 6 years old and still going strong.
Boss

Tezell wrote:Thomas,

the Napa # is 2134011SW.

Thanks Tim!

Granted, the alternator normally supplies a few amps to a charged battery. The point I'm making, the 63 amp alternator is capable of supplying 63 amps if it's trying to to try to keep the charging voltage up. This can happen if there is a fault in the charging system such as a severely discharged battery or a failed battery with a shorted cell. Does it happen every week, no. Can it happen sometime, yes. Does the alternator supply 63 amps all the time, no. Can it supply 63 amps, yes. Can it supply 63 amps continuously into a fault, yes.
Which alternator a person decides to use, either the 10si, Hitachi or other, I recommend a fuse for protection. Modern applications of alternators use fuses or fusible links for protection. It will protect the alternator, wiring and battery.
Gerry

I'm gonna turn this around on you Boss: Why the sudden interest? You've got two threads going on this now.

One big plus to the Hitachi is that it will supposedly fit with no modifications to the bracketry at all. The Delco requires fabrication skills. You've either got to modify the existing bracket, or make a whole new one, or buy additional parts.

Matt Kirsch wrote:I'm gonna turn this around on you Boss: Why the sudden interest? You've got two threads going on this now.

One big plus to the Hitachi is that it will supposedly fit with no modifications to the bracketry at all. The Delco requires fabrication skills. You've either got to modify the existing bracket, or make a whole new one, or buy additional parts.

No sudden interest, I have never cared for the Hitachi, the single wire is easier for most folks to instal and not burn up something.
And judging from the pole most agree with me.