6-volt running volts

[Rjpoog1989]

Howdy,

I have a brand new 6-volt battery in my cub and want to make sure my charging system is working correctly. I have pertronix ignition and 40k volt coil. I’m curious as to what the voltage when running should be. I checked it at the battery and it is 6.4 on low setting and 6.55 on high. I thought I read it should be like 8 volts. I’ve also read that 6-volts pertronix uses a lot of power and not really recommended. Amp gauge is dead center on low setting and showing charge on high. I want to make sure I’m doing the right things for my new battery.

Thoughts?

[ntrenn]

You should see 6.8- 7 volts when charging. 12v battery charges at 13.5-14.0. Anything less than 13.0 on a 12v battery will result in a dead battery. On a generator...you need to check system volts at high idle. Sounds like yours is about right...

[inairam]

Their is a nice post on the voltage drop test on a 6 volt system

http://www.farmallcub.com/phpBB2/viewtopic.php?t=38133

I do like the pertronics ignitions but I have to admit I have not had luck with 6 volt installs. The problem is not with the power draw but with the min volt voltage. The 6 volt system needs at least 5.5 volts to work. The 12 units can go as low as 8.5. so there is more margin of error in the 12 volt set ups at start up.

[John *.?-!.* cub owner]

What you read will depend on the charge of the battery. If the battery charge is low the voltage will be lower than normal till the battery charges up.

[inairam]

John brings up a good point. It may be a good idea to put the battery on a charger overnight and then to the voltage drop test.

I have not done it but there are instructions to make adjustments inside VR to adjust the voltages.

[Rjpoog1989]

Sounds like mine is not doing what it is supposed to. Should be around 7-8 volts. I will run the tests in the above link to see where voltage is being lost. I’m assuming cleaning all connections will help. Is there a way to see how many volts the generator is actually putting out? I’ve polarized mine before, I’m assuming it’s still correct polarity.

[Eugene]

What you read will depend on the charge of the battery. If the battery charge is low the voltage will be lower than normal till the battery charges up.

New batteries out the auto parts store only have about a 60% charge. It will take quite a bit of operating time for the Cub to charge up the battery. John's suggestion of putting the battery on a charger for over night is excellent.

[Rjpoog1989]

What you read will depend on the charge of the battery. If the battery charge is low the voltage will be lower than normal till the battery charges up.

New batteries out the auto parts store only have about a 60% charge. It will take quite a bit of operating time for the Cub to charge up the battery. John's suggestion of putting the battery on a charger for over night is excellent.

I plan on mowing with the cub when I get home. Is it safe to run on high charge for a few hours?

[Eugene]

Yes.

[MiCarl]

Going to chime in too. My '48 is below 7 volts on high charge at high idle. I looked in the service manual (it's at home) and whatever it was was in the correct range. My 6 volt tender (tractor spends long periods parked) always shows a full charge when I connect it.

[Rjpoog1989]

Going to chime in too. My '48 is below 7 volts on high charge at high idle. I looked in the service manual (it's at home) and whatever it was was in the correct range. My 6 volt tender (tractor spends long periods parked) always shows a full charge when I connect it.

That’s interesting. I’ll have to find that in the manual. Mine might’ve been ok before...

[Rjpoog1989]

Now I have totally messed things up... I did the voltage tests and seemed to only be loosing .4 volts, which is acceptable according to the link.

I figured it would be worth my while to take the hood off and clean all the connections at the generator and dash. Figured it could only help. While carrying the hood across the garage I tripped and dropped it and now it’s kinda out of whack. I made up some new curse words at this moment .

I had a beer and calmed down and started cleaning connections and checking continuity of wires and such. I also touched the bat and gen terminals on the cut-out to make sure it was polarized correctly. Oiled the generator also while the hood was off because it’s easier than fishing through those tiny holes.

I was taking the dash off to look at the switch and such and I still had the battery connected which I guess was a mistake. Must’ve bumped something with my socket extension because something started smoking.

Currently the amp gauge reads nothing while running, no loss or charge on any settings. Also running voltage at the battery is 6.3 volts. Battery was fully charged via my charger before starting the tractor. Seems I was better off not messing with things.