Pre-war (up to 1942) 1939 Cad Lasalle polarization at regulator.

[ricardo_padilla]

I reconnected the battery and ran the engine four times each, for 20 minutes at a time, so I could flush the radiator sludge (after 10 flushes, need to have radiator removed/rebuilt).
Engine died the fourth time I ran it, regulator showed carbon build up at contacts (see pics), cleaned them up with fine sand paper.
Question:
1 - Do I have to jump the Battery and Gen/(A) at the regulator each time I reconnect the battery?
2 - Will damage occur (other than pitting at regulator contacts). Fuel gauge did kept reading Empty.

[39LaSalleDriver]

I don't think you have to polarize after disconnecting the battery. That has to do with establishing the magnetic field of the generator as I understand it. If you have already polarized the generator once, it should be good to go. It certainly won't hurt to do it every time you disconnect if you want to though. I will add that if your generator has not been correctly polarized though, it can cause damage to the generator and/or regulator and/or battery.

Points by their very nature will develop some carbon build up, but it shouldn't be excessive. I have a "Manual for the Automotive Technician" which dates to the 40s or 50s which shows the following (attached below).

The fuel gauge is a whole 'nuther issue.

[ricardo_padilla]

Thank you for a prompt response!

I polarized the regulator (jump BAT+GEN) to eliminate any issues unknown to me, ammeter is in the positive side (charging ~7.8 volts), all light working. Wow!

Thank you!

[dawicker]

I'll throw in my 2 cents worth. I am (was - now retired) an electronics engineeer and have been disregarding the don't file instructions my whole life. Yes, they will never be as good as a new one after filing, but I have never had an issue after filing contacts, be they points, relays, or any other electrical device. I think this is advice for someone earning a living by repairing autos to avoid having to deal with problems caused by not removing all the filings and abrasive particles left behind. With proper cleaning, you can avoid this, or worst case maybe give it a second go. Might have been good advice in 1939 when new parts were readily available; different now that it is almost 85 years later!

The contacts may (should) be plated with a noble metal to help prevent corrosion. I doubt this coating would last very long in any case, so the fact you may be removing it by filing is probably moot. So I wouldn't sweat filing them!

Dave Wicker