Keeping the faith, 6 Volt or Bust!!

[Al Martin]

I did buy a new 6 Volt / 165 Amps batteri last week.

And now my generator is charging lesser and lesser, so Im gonna buy a

6 Volt Alternator from: http://www.fifthaveinternetgarage.com/parts/index.html

Anybody know what size the generatror Drive Pulleys

size is on a P20, 218?

Al

[greg g]

Hey Al, Is the new battery discharging? A heavy amp battery because of its reserve may not need the steady rate recharging of a lesser battery. Remember the job of the generator is only to replace the energy that has been used or is being used. That's what the voltage regulator is for to decide when and how much to charge the battery. Did yu test the gennerators operation by momentarily grounding the field post? This bypasses the regulator and will allow the genny to put out its full output. It should peg your ammeter to full charge. If the needle registers full charge, then the gen is working properly. Do not leave it grounded for any longer than you need ot to run the test.

[Plymouthy Adams]

As the alternator will put out lots more current at lower speed than a generator..the stock size pulley with the alternator you be getting will more than not suffice...would say approx...2.5 diameter

[rearview]

I picked up a new one from a guy on ebay, he has one listed right now.

http://cgi.ebay.com/ebaymotors/ALTERNATOR-6-VOLT-POSITIVE-GROUND-GM-STYLE-NEW_W0QQcmdZViewItemQQcategoryZ33574QQihZ009QQitemZ190080501925QQrdZ1

Works great!!

[De Soto Frank]

I'm still running the stock genny, regulator and such in my '41 De Soto... 102,000 un-restored miles, and it's working quite reliably.

Some weeks I will put over 100 miles on the car, then it may sit untouched for a couple of weeks.

Never any issues with dead batteries, charging problems, etc.

I did spend some time during my first year with the car chasing some gremlins in the charging and lighting systems, but once corroded wires, undersizied wires, bad terminations, and poor grounds were corrected, it's been quite reliable for the last nine years & 20,000 miles...

The stock stuff will work...

Good luck,

De Soto Frank

[Al Martin]

rearview, thanks for the ebay tip.

thats nothing wrong with the battery,

its the generator that going bad.

I just wonted to know if Anybody know what size the generators Drive Pulley is on a P20, 218?

Al

[eric wissing]

Al, is looking for this info, which I don't know. • 3/8” Single Groove

• 1/2” thru 3/4” Single Groove

• 3/8” Dual Groove

• 1/2” Dual Groove

• 1/2” and 3/8” Dual Groove ?

[Plymouthy Adams]

I just went and measured the pulley..mine is 3 1/2 inches diameter..and the alternators I have here are 3 inch pulleys....

[Jerry Roberts]

I don't have the answer to your question but I do have literature from 5th avenue reguarding their pully diameter ; " the alternator pulley should be at or close to 2.5 inch diameter . Stock generator pulleys are too large in diameter for alternator applications . etc "

[Lou Earle]

If you want a single wire 6v pos ground alternator many A model places like Mike's Affordable A or Brattain's carries them. They are already equipped with the smaller wide pulley needed. I have 2 or 3 on different cars.

However, I only change over if some aspect of my old system fails.

Try this- turn you headlight on for a hour or 2 then start your car- I bet the amp Gage will jump then!! I had same thing happen when I went to good battery- even running at night very little charging. Your system I do not believer failed because of a new battery I think the new battery is hefty and well charged ( that is a whole nother topic!! How to charge a battery) so it doesn't draw as the other did.

I have been told that the generator system is better for charging up a system than the alternator - not sure about that .

Lou

[James_Douglas]

I have purchased stuff from 5th ave and I have not had any issues. With regards to their 1-wire alternators, be advised that they are NEGATIVE ground and if you have a radio it will kill it. The Motorola radio has things in it that are polarity sensitive.

I do not know why Randy (5th ave) does not sell the positive ground version.

I took my Delco 10SI apart and figured out how they make them positive ground and it is simple.

*************

Six Volt Positive Ground Alternator

Transpo Electronics

2150 Brengle Ave.

Orlando, FL 32808

USA

TECHNICAL SUPPORT / ENGINEERING HOTLINE: 1-800-327-6903

Tech support said to look out for the air gap between the armature and the stator as this is directly related to how fast the unit will self excite. Look for armatures that don’t look like they have been cut a lot and have smooth rounded edges. If they look shinny and new they are new ones made in China and the metallurgy is not as good as the older USA made ones. Look for cases when looking for cores to re-build with “686” on the back. These are older OEM units.

For the 10SI alternator use a Transpro 6 volt Voltage Regulator:

1. D10SE6 (7.7 volt)

OR

2. D10SE8 (8.0 Volt) unit.

Also needed is a Positive Ground Rectifier part number DR5045

(Note: if you want to use the larger case alternator called a 15SI use the DR5075 Rectifier and one of the above Voltage Regulators. He said with the larger alternator you get more output at lower RPM, BUT if the air gap is too big the engine RPM to get it to excite will be greater)

For an emergency road kit keep a Voltage Regulator, a Rectifier, a set of bearings, and a brush holder in a little bag. Any shop can build up a unit with these parts as the housing and armatures are all readily available for the 10SI units.

Here is the text on how to modify a unit for 6 volt positive ground operation:

For the 6,or 12 volt positive ground application you must wire the alternator like the one in the photo below

Three screws hold down the brush holder assembly and voltage regulator. All three must be insulated (any alternator shop can give you an extra bolt insulator or take one out of another 10SI core) which is different that the negative ground system which only has two screws insulated.

After the positive ground rectifier has been insulated a jumper wire needs to be made as shown in the photo.

{Note: The voltage regulator in a positive ground alternator is still negative ground. The only component that makes the alternator positive ground is the rectifier}

So, a jumper wire (in Red in the photo) is connected between the (negative) "Battery" stud on the rectifier to the ground screw for the voltage regulator.

The terminal on the red wire must contact the ground clip on the brush holder. It must not make any contact with the screw itself.

When connecting the stator wires to the rectifier block as seen in the photo, observe the three wire nuts. The three stator wire ring terminals must be lifted to clear the finned part of the rectifier. Heat shrink tubing on the leads can be used for an extra margin of insuring that these leads don’t short to the heat sink.

{Note:The stator leads shorted to the rectifier or inside of case has been a problem, I used liquid wire insulation and made sure the leads were coated down to the edge of the rings termianls}

When the alternator is back together and read for use it will require being excited.

To excite a positive ground alternator a jumper wire is run from the case (positive power) to the number one spade terminal on the alternator.

While the vehicle is running momentarily touch the jumper wire between the case and the number one terminal. At this point the alternator should begin charging. Once the vehicle is run up above the idle speed the alternator should self energize and begin providing voltage of approximately 7.5 volts.

[Al Martin]

Thanks for the Info guys.

Anobody know how Wide the gen, drive pulley Groove is?

Al

[55 Fargo]

Al, here in Manitoba Canada in a near by town there is an auto electric shop that makes 6 volt positive ground GM single wire alts for around $100.00 US. If your interested I may be able to connect you with George of Georges Auto Electric, in Selkirk Manitoba..........Fred

[grey beard]

James,

Why in the world would anyone want to change an alternator from neg to pos ground? Just swap the battery cables around - hook the negative cable to the ground and the pos to the starter - and use the neg ground alternator out of the box. The only thing on our old MoPars that is positive ground is the charging system. If you're changing that - alt and reg combined - why change it to pos ground. Absolutely no advantage in the swap, except that's how they were made - but then they weren't made with alternators either. Nothing on the enire vehicle will care if the charging system is pos or neg - nothing but the charging system is polarity sensitive - unless you have a transistor radio from a later time. JMHO:(

[James_Douglas]

You will kill the vibrator in the radio over time if you switch the ground.

James

[martybose]

You will kill the vibrator in the radio over time if you switch the ground.

James

My 802 worked fine for several years using a 5th Ave. neg ground 6V alternator. I was warned that if the vibrator had been replaced with an electronic one it wouldn't work, however.

5th Ave. does have the correct pulley for their alternator; you just need to specify you want the wide groove one.

Marty

[Normspeed]

Wow, reading this thread makes me glad I stuck with the old reliable 6 volt pos ground and a generator. Starts good, charges just fine, and with the 12 volt step up for a radio, no worries.

[Al Martin]

I picked up a new one from a guy on ebay, he has one listed right now.

http://cgi.ebay.com/ebaymotors/ALTERNATOR-6-VOLT-POSITIVE-GROUND-GM-STYLE-NEW_W0QQcmdZViewItemQQcategoryZ33574QQihZ009QQitemZ190080501925QQrdZ1

Works great!!

Im going for the Neg ground Alt.

I asked the guy on ebay: autoelectricandbattery1171,

about the output the Alternator that he got for Sale would give.

This is the Response from: autoelectricandbattery1171..

eBay Item: ALTERNATOR 6 VOLT POSITIVE GROUND GM STYLE NEW (190080501925)

This message was sent while the listing was active.

"Hi, the idle output will vary depending on your crank pulley size.

The average is 20 amps. Maximum output is 45 amps."

=========================================

Looks like it gives very low average Amp & only 40 Amp at Max.

I want more Amps.

Check this one out:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=015&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=250102353456&rd=1,1

"These alternators will provide 60 amp maximum with around 40 amp at idle."

Only $ 95.00.

But they look very similar to eatch other.

I think I go for this one.

5 th Ave,s is to much money.

What do you think Guys??

Al

[rearview]

All the GM sub-100 amp all use the same case, different guts... The one I got from the guy is 63 amp, more than enough to run this car. I measured 52 amp output using my shunt.. where he got 40 is anybody's guess.