6 volt neg gr

coverton

I just had a 6 volt alternator built-GM -from the 70's. All my cronies say to change over to neg gr ? well I realise the radio and lights don't know the difference,but how about the Starter and the Heater motor ? Will it make a difference to them ? Found a JC Whitney 6-12 module for a FM/CD radio to put on a hump mt. JCW Part # 813905 list for $69.99 Also I need to get a wider 3/4 " pulley for the alt ? Any ideas ?

"O"

Aaron D. IL

I heard from another Hudson comrade that when he went to a 6V neg ground alternator his Radio didn't work right......I cannot verify this though.

Unknown

YOUR RADIO SHOULD WORK EITHER WAY WITHOUT ANY DAMAGE TO IT, bill albright

Unknown

Bill's right, all the lights and radio should work as normal. It's the voltage that's the issue, not the polarity. As long as everything is polarized to either negative or positive ground, things should work as intended.

Unknown

coverton wrote:

I just had a 6 volt alternator built-GM -from the 70's. All my cronies say to change over to neg gr ? well I realise the radio and lights don't know the difference,but how about the Starter and the Heater motor ? Will it make a difference to them ? Found a JC Whitney 6-12 module for a FM/CD radio to put on a hump mt. JCW Part # 813905 list for $69.99 Also I need to get a wider 3/4 " pulley for the alt ? Any ideas ?
"O"

I guess you already have the Alternator. I just wanted to post that I purchased a 6 Volt positive ground alternator and it works perfectly. I used a mount purchased from Ken Ufheil of Plano Texas and the standard pulleys. In the future I will be installing a Japanese mini air-conditioning compressor...again using a KU mount and at that time will install the dual belt crankshaft pulley. The pulley will allow me to run two individual belts to each of these devices. To assure the radiator will cool, I have a 6volt radiator fan that will mount to the front of the radiator once the air has been installed.

Good luck on your change over.

Park_W

Carroll,



The radio is the only thing that's possilbly polarity sensitive on these cars, and many radios are not (depends on design of the radio's internal power supply). The original generator pulley will fit onto the GM alternators, though the pulley is larger diameter, so the alt. won't turn as fast, thus won't charge as well as normal at idle speeds.

hudsonguy

You can also just buy a new GM style alternator pulley from any number of aftermarket suppliers. I got one for around $10 or less, and that way didn't have to disturb my Hudson pulley. Can't for the life of me find any info on it, but it was one of the many street rod accessory suppliers.

coverton

My alternator guru put a pos gr rectifier in the GM alt so I won't have to change much at all. He said the pos rectifier was only 18 bucks? Think I will mt the JC Whitney 6 to 12 volt converter where the voltage regulator was.

This will allow me to put a AM FM CD in the glove box and isolate any chance of reversingthe neg gr it needs to work properly ? Will hunt around for a proper size pulley