1948 Chrysler Windsor problems, Generator not working, and fuel gauge not working

[dalef62]

I am working on a customers 1948 Chrysler Windsor and I am working out the last few problems.  This car has been sitting for at least 40 years and when I got it the engine was out and stuck.  It has just over 98K for miles.  

The first problem is that the generator is not putting out any voltage.  While it was on the vehicle I polarized it and checked all the wires to make sure they were all hooked up properly, still no output.   I have removed it from the vehicle and tried the motoring test and it does motor, but when I take the ground off the Field post it slows down.  I was looking online and when you remove the field to ground wire the generator should speed up, is this correct?  It is positive ground and I have checked the brushes and they look good.  What other things should I check to see what is wrong with it? 

Also the fuel gauge is not working and I have removed the sending unit from the tank and it is a cork float(and it does float!), the arm is free and is moving up and down.  It has two connections on the top of the sending unit, marked "1" and "2".  I replaced the wires to the same terminals but it still does not work?  I even switched them thinking that someone else might have been messing with it years ago, as the cover was off the in the trunk exposing the sending unit, and it still didn't work.  The tank has a good ground.  I ohm'ed each terminal to ground and when I moved the gauge the readings changed like I think they should.  What is a good way to check to see if the gauge in the dash is good? 

I HAVE a shop manual but they don't go too deep into the generator or fuel gauge other than with the fuel gauge to get a known good one and hook it up and see if the dash gauge works... 

Finding shops that will work on the generator are getting hard to find in my area.

Thanks for any help offered

Dale  

[TerryB]

Voltage regulator working ok?  Regulator points stuck or corroded?

[dalef62]

48 minutes ago, TerryB said:

Voltage regulator working ok?  Regulator points stuck or corroded?

 

Regulator seems to be working ok, all the points are clean and free.

[TerryB]

I’d try polarizing it again.  Seems like a good thing to do after the testing you just did.

 

 

[trini]

From what you are saying the problem is ground. REBOOT .Wire may seem to be grounded but the are not,  No. 1 , engine to frame to battery is the starting pint. No use running around  until this first step 

[dalef62]

11 hours ago, trini said:

From what you are saying the problem is ground. REBOOT .Wire may seem to be grounded but the are not,  No. 1 , engine to frame to battery is the starting pint. No use running around  until this first step 

Grounds are all good, new cables.

[F&J]

20 hours ago, dalef62 said:

The first problem is that the generator is not putting out any voltage.

To test a generator by itself:

 

On GM and Mopar Generators, remove all wires from F and Batt/Arm terminals.  Then hook a voltmeter lead to the Batt/Arm terminal,  and the other test lead to a good ground.

 

Run the engine up to 1500-1800rpm, then jump the F terminal to a good ground for just long enough to see if the voltage goes wild, meaning it should 'pin' the needle on an analog meter.   Don't leave the F jumped for very long as the generator is running way beyond specs.  If you do this and only show a couple of volts or less, the generator is not working.

 

On Fords, you put power to the F to do the test.

 

If a generator was dormant for decades, it might have lost it's residual magnetic charge, and that is restored by when you said you motored it, or you polarize it.  You've done that already, so do the test above.

[c49er]

Do as F&J says....if the voltage shoots up 8 to 15 volts or more generator is good.

Then your problem is more than likely a voltage regulator...

Re- polarize the generator...

Make sure the generator regulator wiring looks like it has not been cut up sliced etc. 

Dirty regulator points maybe corroded...those closed contacts a delicate issue to deal with if you have never done it.

A clean NOS factory Autolite regulator is the way I do these regulator jobs.

Hunt them down on ebay etc.

Modern chinese regulators are junk.