Mun24ster

Update 6 volt to 12 volt on my 1940 special

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I am currently switching my 40 Buick to 12 volts. I have removed the generator and put in an alternator with a self contained voltage regulator, thus eliminating the car's original. I put in the required ignition coil. Also replaced the starter solenoid. Of course replaced the battery to a 12 volt. Made all the wiring changes according to the info sent to me by vintage auto garage, where I purchased the kit. My 40 Buick method of starting the vehicle has been switched to a push button start. Now is where I am stuck. When I push the button, I am getting a clicking sound as if its trying to send power thru, but nothing is turning over on the engine. Am I missing a wire to some place, sounds electrical problem to me, but I don't have a clue. Any help would greatly be appreciated.

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Benefits of AACA Membership.

Sounds like the solenoid is not working or the starter is cooked. It could also be the starter button, the wiring, the ignition switch, or the battery. I would guess the solenoid is bad since it's the cheapest part. Start there.

 

Sadly, you're pretty far down the conversion road and diagnostics are going to be a lot more difficult. Is there a specific reason you're converting to 12 volts? It complicates things considerably when things don't work because it doubles the number of things that could go wrong. Instead of making things easier, it often makes things more challenging when trying to maintain a vintage car.

 

Anyway, if power is going to the solenoid, your battery is fully charged and load tested, and the wiring is good, then somehow it's not kicking power to the starter. That's the solenoid's job, and it doesn't sound like it's getting done.

 

I would also wager that if you put all the 6V parts back in, it would start...

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Go over the electrical diagram.     The electrical system is very simple.     The only thing that most people miss is the grounding circuit that goes thru the regulator.   The solenoid has only two wires.   One goes to ground (thru the regulator) and the other gets its power from the starter button circuit.    Use the original 6 volt starter and solenoid.    They work fine.     Wiring size is more than sufficient when going to 12 volts.        Get the newer 12 volt head lights that are about  35 /55 watts.      The original were  I believe  25 / 25 watts.    I just had my '35' 50 series head lights recoated by a guy in Michigan.  ( Vacuum Orna-Metal ,  Frank @ 800-827-6762 ).     They look like mirrors.    I am converted to halogen bulbs.   Details if wanted.   

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Posted (edited)

the simplest answer is the battery posts. 

 

Check the connection of the heavy "hot" cable on the solenoid terminal.

Also check the heavy copper strap  connections from the other solenoid terminal to the starter case.

All of the starter current...which is a lot of amps...has to go thru

the solenoid so these connections really have to be good

 

Is the battery voltage at 12V or so  ?

 

I suggest these in the vein of "easy things first"

 

I suppose you still are using the original battery cables ( for 6V service )...these 

are plenty heavy enough  for 12V use

 

Jack Worstell

Edited by Jack Worstell
Clarification (see edit history)

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Yep, sounds like the "Kit" did not know the Buick wiring. The two ways to fix this, 1. go back to 6 volts and motor on. 2. Complain to  vintage auto garage that their kit did not replace the Buick wiring properly and now the solenoid does not pull in. Get them to understand it is their error. Have fun!🤣

 

See Jim's explanation above to the error.

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6 volt fuel gauges fail on 12 volts  a reducer is needed

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When I did mine,  I used Rhode Island Wire.   They sell partials such as 'Dash to engine' wiring.       My 35-57  and my '38-46s' wiring needed help.    Their kits are well documented,  labeled and easy ( ?) to  understand and install.    Is your wiring is decent shape ?      Both My '38'  and '35' needed help 'safety wise'.     One thing in the conversion is '12 volt systems are common'.   for those who are not electrical talented.      Jay at Vintage is a fair guy but I suspect he bought a system that someone put together for resale.     Converting to 12 volts is fairly easy.    All lighting bulbs are replaced with 12 volt bulbs.   You did the correct upgrades to the  ignition coil to 12 v.    The original  6 volt starter / solenoid assembly works nicely on 12 volts.   BTW,   removing  the regulator removed the built-in ground for the starting circuit.    That system was designed to use a coil in the regulator to keep the car from trying to start again after the engine is running by disconnecting that part of the start  circuit.      One of the two wires going to the starter solenoid goes to the regulator..    by running that wire a good engine ground will fix  - eliminate that factory  generator safety circuit as you use the much better alternator.   The other wire leaving the solenoid goes to the vacuum start circuit.   I really hope you installed a 3 wire alternator.   The single wire alt does not put out until you get going.      Google '3 wire alternators' for a good education on them.    By wiring a normally open push button across the original vacuum start circuit - by passing it so it cannot work,    that lets you start the engine ONLY when you push the button.    Now if you have a solenoid issue - that is a starter / generator repair shop fix.    They have the instrumentation to check out and repair problems.      Study your Buick provided service manual  (you have one right  ? )  and they have a pretty good electrical diagram.    Remember,   their diagram is electrical circuits and a "not as actually wired" diagram..  electrically wired per the service manual when chasing problems but  - well, get your buddy to explain just how.   You will become a good fixer of their fairly simple designed electrical ...     much is duplicated year to year with minor improvements for increased complexity. 

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Yes,   I forgot that you must use a 'Runtz'  voltage controller for the gas gage.    You will cause failure it not used.     There are some others but  Runtz is the best.     You don't want to replace the sending unit or have the gas gage repaired. - - -,     

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Well,  there is one other item that needs modification.    The heater is wired for 6 volts but you can get a wire wound voltage reducer to keep things kosher.    You can get  some mid 50's heater blower motors that are 12 volts.     I think I have covered everything  - - I  hope,   I think its 'old timers disease' creeping up on me - - -  ya man.......

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Oh, and the clock.

 

And the radio.

 

And the ammeter.

 

And the horn relay.

 

And the defroster motor.

 

And the turn signal relay.

 

All that stuff is already in the car. Why is 12 volts better, again?

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Fix it till it’s broke............1940 Buick’s have driven millions of miles.......the 6 volt set up from new was definitely no good.

 

To be fair to the original poster, most people have no clue why they are doing this, thinking the car will be better. It will not. Just like the electric fuel pump that is most certainly wired incorrectly, and unsafe. Par for the course. David Dunbar Buick is rolling over in his unmarked grave.

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It doesn't help that some of the Motor Trend TV channel shows suggest that old cars should be upgraded to 12 volts (Fantomworks, etc.). What, no 6 volt bluetooth???

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Yup.

That and since the late 1980’s it seems like every 3d ad for a prewar (non-Ford) car advertised in HMN said, “Upgraded to 12 volts!”

Maybe I’m exaggerating that, but it’s heavily sold and has been for a while. Not until I got on this forum did I ever hear anybody question it or point out its pitfalls. Glad I was always too broke to try it...

(Whatever happened to that product that was supposed to keep your car from rusting by sending a near constant electric current through the frame and body panels? Never heard anybody say anything bad about that either but it’s gone.)

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Doing an extensive restoration on my bucket of junk and decided to convert to 12 volt.  

Probably should have given six volt a chance since everything will be new.

Seems everything I remember about 6 volt meant dim lights and slow engine cranking,  but as long as it didn't take too much to get it started maybe I should have just lived with the dim lights.

 

I like how some people make sarcastic comments about the phrase " upgraded to 12 volt "!

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I converted my 1940 Special to 12V because I couldn't find a "check engine" light that was 6V. And when I wired the doors to make a dinging sound when they were ajar, they were all 12V. I put seat belts in the car, but the seat belt warning light I installed was too dim on 6V and was hard to see, I was afraid I wouldn't see it and forget to put my seatbelt on. This could lead to death, so I converted the car to 12V for safety reasons.

 

NOT!!

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ALL WASTED WORDS, folks. OP has not been back since the question.

 

  My 12V conversion was trouble free 10 years ago and still is. Very happy with the performance of same.

 

  Ben

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Yes, but you found it hard to get a 6 volt fuel injection system!😄

 

 

On 5/30/2020 at 1:07 AM, 1937McBuick said:

 

I like how some people make sarcastic comments about the phrase " upgraded to 12 volt "!

 

Because if only changing the system from 6 to 12 volts, with no other accessory modifications, it is a waste of time and energy, not an upgrade.

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We all choose to punish ourselves in our own ways.  Some work on old cars, some go into social work.

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On 5/30/2020 at 12:07 AM, 1937McBuick said:

Doing an extensive restoration on my bucket of junk and decided to convert to 12 volt.  

Probably should have given six volt a chance since everything will be new.

Seems everything I remember about 6 volt meant dim lights and slow engine cranking,  but as long as it didn't take too much to get it started maybe I should have just lived with the dim lights.

 

I like how some people make sarcastic comments about the phrase " upgraded to 12 volt "!

 

 Just have to consider the source.  I HAVE NEVER BEEN SORRY I changed to 12V.  Ten years and almost 20,000 miles. Replaced the 12V battery after 9 years.

 

  That's my story and I'm sticking to it.

 

  Ben

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I don't see why you didn't just upgrade to 120V AC and get a Maytag.

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7 minutes ago, Morgan Wright said:

I don't see why you didn't just upgrade to 120V AC and get a Maytag.


Best laugh I had In days.👍

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2 hours ago, Morgan Wright said:

I don't see why you didn't just upgrade to 120V AC and get a Maytag.

 

 Well, had I done so, you would have found something wrong with THAT,😜

 

  Ben

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I'm kinda new here and have the mentality of "live and let live".

I made a choice and am going to live with it.

This car will be very well restored and I'd like it to be close to original,  it won't be competeing in any car shows that matter!

I am fussy and more money is being spent on this car than makes sense,  but I'm not doing it to make money on it....I'm fulfilling my 30 plus year old dream.  I want to drive this car,  enjoy it,  and take care of it.  

 

To each his own....

 

Let's help each other and respect each other's opinions at the same time.

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20 hours ago, 1937McBuick said:

I'm kinda new here and have the mentality of "live and let live".

I made a choice and am going to live with it.

This car will be very well restored and I'd like it to be close to original,  it won't be competing in any car shows that matter!

I am fussy and more money is being spent on this car than makes sense,  but I'm not doing it to make money on it....I'm fulfilling my 30 plus year old dream.  I want to drive this car,  enjoy it,  and take care of it.  

 

To each his own....

 

Let's help each other and respect each other's opinions at the same time.

 

I also in the driving category,  but I have lot older cars.  Over all, I strive to be the same as from the factory, except for safety items.  Some of those items include replacing the wood in the wheels with new wood, upgrading the wheel bearings from ball bearings to tapered bearings, and adding stop light, etc.

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9 hours ago, Larry Schramm said:

Over all, I strive to be the same as from the factory, ....

 

If it's not same as from the factory, it's not a Buick.

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