6 volt starter

[motorman]

Hello l have a 1951 Cad. with a 331 cu.in motor it has a 6 volt starter and would like to know if

anyone installed a 12 volt from a later Cad like 54 55. Would the 2 bolt hole line up trying to lose the slow cranking

of a 6 volt.Thanks in advance.

[The Old Guy]

I raced a Caddy powered Chev back in the late 50s, and had trouble starting it when it was hot because it had 11-1 compression. It was a 365 Cad from 1956. I solved the problem by using a 6 volt starter and running 12 volts to it. I had the car for 5 years ,and never experienced any problem with the starter. It seemed to thrive on 12 volts.

[Packard enthus.]

wouldn't it be simplier just to properly repair your Cadillac so it starts the way it did when in service? Here's a thought...what do YOU think...? do you really think people, once we got past the early 1920's, would accept slow starting when these cars were in service..?

My own favorite sadistic "stunt" at car shows, when people watch how fast my Packard V-12 cranks over, is to tell them that I have the special "four volt conversion", explaining that modern 6 volt batteries just dont have the proper "oompf"....but with the special four volt battery, it (as I demonstrate)...starts right up.

Can you believe this...a year or so after I first pulled that "stunt"...at another auto show in another part of the state, I actually heard some jerk officiously explaining to another on-looker, when a stock 6 volt car started right up..."see....there's one of those four volt conversions I was telling you about..."

[Guest ZondaC12]

id also like to add that my 38 does just fine. sure doesnt spin nearly as fast as my '87 cougar 5.0L v8 but actually by the sound the speed seems about the same as a lot of modern smaller v6 engines. and i can tell its not struggling to get there either. futhermore the speed is more than adequate to get it running. it actually cranked pretty slow when i first pulled the car out of its cave, but then i pulled off the starter and found that the nut holding cable from the solenoid to the starter was VERY loose, and, the solenoid wasnt too well. the big washer that gets slammed into two metal stubs to make the connection was hitting at an angle and making poor contact. i pulled that apart and shimmed one of them a little, and fixed that loose short cable, and i was amazed at the difference it made. sure is a nice feeling stepping on that pedal now!

although the battery cables i got at NAPA with the battery. someone told me at a show once that these 6v cars actually had thicker wire. i might get some just for the heck of it, to get every last bit out <img src="http://forums.aaca.org/images/graemlins/laugh.gif" alt="" /> anyone know where i could get that? would a generic auto parts place have that? maybe a cable for a big diesel engine?

[Guest AntarcticDave]

Hi Paul,

Most of the old timers here tell me the best thing to do is buy the clamps and get some 00 gauge welding cable, and make your own. The 6 volt on my 47 Cadillac does just fine as is too.

Dave

[Mark Shaw]

You can get away with running 12 volts to a 6 volt starter as long as you don't crank it too long.

Another good idea, is to connect a ground cable directly from the battery to a mounting bolt on the starter.

Heavy 6 volt cables are a must to handle the amperage of the 6 volt system. If you already have 12 volt cables, maybe you should use one to ground the starter.

[Jon37]

Motorman, why not try a couple things to improve your present 6-volt situation before you take the big leap to a different starter?

1). Are your cables the correct gauge for 6-volt? If someone has installed a modern (smaller-gauge) 12-volt cable at some point, this could be your problem. Not only would you have hard starting but the cables would heat up as well. Try Antique Auto Battery http://www.antiqueautobattery.com/ , or if you have a local auto electric company they might have the cables you need. Also, if you patronize any specialty Cadillac parts suppliers, they might have the right cable in the precise length for your year of Cadillac.

2). Is the battery adequate, and is it fairly new? Make sure yours is in good condition. When buying 6-volt batteries make sure you get one with a good Cold Cranking Amp (CCA) rating. Mine, for example, is made by DEKA and has 780 CCA; it is a Group 2 (fairly standard) and only cost me $60-70. The new Optima batteries have even greater CCA ratings but are much more expensive. Don't buy something with a CCA rating in the 400's.

3). Are all battery terminals and clamps, clean and bright? If you haven't checked lately, then go over them with a battery terminal cleaning device and see if the starter works any better.

4). Is the battery ground strap in decent shape, and does it connect both to the engine and the car frame? (Sometimes the battery goes to the frame, and there is a separate ground strap from frame to engine or transmission, elsewhere.)

5). If everything else is okay, then perhaps the starter is indeed at fault. A good local auto electric shop can overhaul it. I had my 1937 starter (and generator) overhauled locally.

Of course, there can be many other reasons the car isn't ''catching'', but from what you say it sounds like the starter itself is turning over slowly. If it's barely getting enough power (for any of the reasons outlined above) then it's using all the ''juice'' to turn itself over and has nothing extra to spare for the ignition.

Six-volt systems are generally less forgiving than 12-volt systems. But if you make sure all your connections are in tip-top condition, the system should work adequately. As someone said, above, these things worked when they were new. A bit of rejuvenation may bring them back to youthful condition again, without the necessity of experiemnting with non-original starters

[Guest Albert]

Another thing that i have found with my 6V packard is there is no margen for poor ignition or carburator. The starter only turns the motor over fast enought to start the firing process of each cylinder, once the cylinders start to fire they will ease the load on the starter and help to spin it faster to start the engine. So if the fuel mix or ignition is out it takes a lot more cranking. You will find it may take a while if the car has been setting for a while to get the gas into the carb, this is where and electric fuel pump comes in handy. but my Packard sat all winter with the battery in it and it started back up in the spring on it own without even putting the charger on it..

[critterpainter]

If my feeble memory serves me correctly, the starter on that car sits rather low on the flywheel.

If the main bearings are tired the crankshaft drops ever so slightly putting a load on the starter (the starter is trying to "lift" the engine). You my need to put new mains in the old gal

bill

[motorman]

Thanks i found the hard starting problem, #1 and #3 piston rings were stuck and this made the motor to tight

to turn,I will rebuilt and i am sure the 6-volt starter will crank like it did in 1951. Thank,s