Jump to content

1948 Plymouth Deluxe Radio and Clock Wiring?


jim6346

Recommended Posts

Hello,

 

 I am doing a 12V upgrade to a 1948 Plymouth Special Deluxe. I have a 6V stepdown for the clock, gas gauge, radio, and blower

motor. However, I can not find any wiring diagram for a P15 that shows these (other then the fuel gauge). Can I use the P17 wiring

diagram? Or does anyone have a wiring diagram for a P15 that shows these?

 

Thnks,

Jim

Link to comment
Share on other sites

Yep, have this one, but it does not show the radio, clock, and blower motor for some reason....

 

Thanks!!

Jim

 

Would the 49 model wire diagram help you Jim? I checked one of my manuals and see that it appears very similar to the 48 model wire diagram but also has the radio, clock and blower included.  

Link to comment
Share on other sites

Really the only thing in the dashboard that uses electricity is the fuel guage. The other accessories are an after thought and are wired direct from the ignition switch to the unit outside of the wire loom. The 6 volt heater's windings are heavier than 12 volt heaters and will run faster but will take 12 volts very well. All that is needed for the clock and radio is a low cost reducer wired in front of each unit. This ain't rocket science. Its an old car! . 

Link to comment
Share on other sites

Thanks everyone, I was able to squeeze under the dash and trace back all the wiring.

 

I installed a 6V stepdown for the radio, blower motor, sending unit, and clock. So far everything seems to be working well except the fuel gauge.

It reads 1/4 tank even though it is completely empty. Measured the sending unit and it reads 0-32 ohms. Any ideas?

 

Also, this may be a stupid question but I am new to these, do the front marker lights go out when you turn the headlights on? They work

with the switch halfway out, then turn off when I pull it all the way out.

 

Thanks,

Jim

Link to comment
Share on other sites

With the sending unit out of the car, does the gauge move while you lift the float arm up and down? I always install a redundant ground on mopar sending units just to insure trouble free operation.  If your sending unit is held in by a ring with screws in it, crimp an eyelet to a piece of wire and run one of the screws through the eyelet and the other end screw it down to a clean piece of sheet metal. If yours is held in by the locking ring, you can solder the wire to the top of the sending unit then screw the other end of the wire down into clean sheet metal. I have saved myself a lot of time and money by adding this ground and restoring fuel gauge operation vs. buying new sending units.

Link to comment
Share on other sites

I put one on my fuel gauge only. It is said the guage doesn't know the difference and works on 6 or 12 volts. My clock doesn't know the difference either and has been working well for years now on 12 volts. I installed a later 12v heater motor but I used the 6v one on low for years with no issues. This was all on my 49. BTW the starter doesn't care either just don't grind on it too long. Don't forget the 12v coil and you are good. I would think the radio will be more unhappy about changing polarity than voltage.

Link to comment
Share on other sites

Condenser change with the 12v. changeover? 

Won't think so, but thought I'd throw out the question.  :huh:

 

Doug

Link to comment
Share on other sites

Condenser change with the 12v. changeover? 

Won't think so, but thought I'd throw out the question.  :huh:

 

Doug

Normally on a 12 volt conversion a ballast resistor is also installed feeding the coil (or a coil with a built in resistor is used) with reduced voltage. Therfore the points and condensor are also reduced to something close to 6 volts.

 

On my conversion I also installed a Ford 4 pole starter solenoid. The unused pole is powered up with a full 12 volts everytime the starter is engaged. I wired this pole directly to the power side of my coil thus giving me a full 12 volts to the ignition system for startup.

 

coil.jpg

 

MVC-002F-1.jpg

 

solenoid.jpg

Link to comment
Share on other sites

Thanks for the response Don,

 

Doug

Link to comment
Share on other sites

OK, something new now. When the car is running, the fuel gauge fluctuates all over the place, from full to empty to

everything in between. Ran another ground wire from the sending unit to the body, does the same thing. Anyone seen this before?

Link to comment
Share on other sites

Do you mean it is moving as you drive or while stationary? My D34's gaige moves as the gas sloshes around the tank.

On the parking lights, I wonder if the reason for them shutting off when the headlights are on would be to redude the lead on the generator.

My 1965 VW Karmann Ghia, also originally 6V, does the same thing. And my dad's 1956 Jaguar XK140 has fog lights, which when on, the headlight turn off.

Link to comment
Share on other sites

On my 39 Desoto the fist stop on the light swith operate the small parking lights in the headlight. The second stop on the way out turns the parking lights off and then turns on the low beams.

 

This is a standard in cars.  Even with your modern cars you can just turn on your parking lights at the first stop on the light switch and then the second stop is the low beams.  On some modern cars the running lights stay on but would still think they would go off.

 

Go try this on  your modern car. Most owners manual glovebox manual will even tell you this info even in your old cars it does.

 

Rich HArtung

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use