1974 MF-135 Gas Perkins - Need Electrical Help / Advice

[Marty13574]

1974 MF-135, Gasser, Perkins AG3-152, 12v Negative Ground.

The only working gauge when I recently acquired was good oil pressure & coolant temp. I installed new voltmeter & new fuel gauge w/sender. Power lead from fuel gauge was connected to terminal #4 of external voltage regulator, so I connected new voltmeter '+' to same location. Cranked up and engine ran great and new voltmeter & fuel gauge worked, but voltmeter was reading 17 volts.

I removed battery and replaced external voltage regulator. When all back together, now no power to regulator terminal #4 so no reading on new voltmeter or fuel gauge.

I read about polarizing but wasn't sure how to do that or if it was needed.

Any help and/or advice greatly appreciated and thanks in advance.

 

[Marty13574]

Ok, figured it out and changed, now seems ok.

I found an older thread where someone knowledgeable said the regulator could have no voltage at regulator terminal #4 when using the 10DN type alternators. So, I checked voltage with meter at the B (#2) regulator terminal and it seemed to be the correct one; no voltage with ignition switch off, battery voltage with ignition on, and 14-15 volts with engine running. So I connected the hots of the fuel gauge and voltmeter leads to this terminal and everything seems happy. Ran it for about 40 minutes.