Generator - How to Test

Battery charging issue seems to be a common problem with our vintage British cars. Here the Moss Motors Tech specialist walk you through checking your generator to see if it is functioning properly. Does the problem lie in the generator, wiring or voltage regulator. This video will help you eliminate one of the culprits. See our How to Test your Voltage Regulator to get the rest of the story.

Category:

Autos & Vehicles

Tags:

• generator
• voltage
• regulator
• charge
• eletrical
• wiring
• mg
• triumph
• jaguar
• mini
• austin
• healey
• moss
• motors

[MossMotorsCom]

To the battery or any cables connected to the battery.

[Reedynn]

@efhask No, don't have the motor running, he wasn't spinning the pulley during the video.

Another, simpler (less specific) test is MOTORING a generator. Look that one up.

[efhask]

If I try this test in the car (rather than on the bench) should I have the engine running or not? I'm confused. Thanks for the videos!

[jghobbies]

Hi, is this test done on the car or bench? Although you were doing it on a bench, I don't understand how ur generator was making voltage without spinning. From my understanding you have the generator d+ on battery voltage, the body grounded, and you apply battery + to the field?

[jammin1033]

i have a serious problem! i have a marine onan 7.5kw generator.. and it runs fine... but it jumps between 50 and 150 volts.. if i turn a light on it dims .. and brightens in a matter of seconds what is this problem? a voltage regulator problem? HELP

[domyaska]

THANKS A LOT FOR YOUR EXCELLENT TUTORIAL VIDEOS

[Snowgoer05]

Its simple! to test it without removing the generator.. just use the battery cable to the generator to the field coil and then test voltage at the battery! it should clime slowly.. as voltage goes up in the field output voltage goes up causing a constant raise in voltage until its at its max and probably overheating

[muttsaball10]

HELP!!! Volt meter to battery in car got that. Do you use a different battery to touch to the df field? If I use the in car battery in the car as a know power source will it climb? I have a battery charger I could use as another battery

[Wirewheels]

I'm confused too - is the voltmeter connected to the battery that is then connected to the generator?? It would be helpful to see where the wires go to that are in the video.

[JCarloss1]

Sorry but the "known power source" is what? Thanks