JD 420 GENERATOR

[TURNER]

HELP, WHAT WOULD CAUSE A 6 VOLT SYSTEM TO LOSE POLARITY AT LOW RPM?

 

[buickanddeere]

???
Are referring to how the ammeter backs off from the + side where it sits when revved up.
Then the needle swings past zero and into the - side when at idle? And the swing to - is farther when the lights are turned on at idle?

 

[TURNER]

WHAT I AM REFERING TO IS AT IDLE IT TOTALLY LOSES POLARITY, DOES NOT CHARGE,ANOTHER WORDS IF YOU PULL THE GROUND OFF THE TRACTOR WILL CUT OFF!COULD IT BE THE GEN?

 

[buickanddeere]

Please explain more and click off the cap lock if you would.

 

[TURNER]

Sorry about the cap lock, I have a 420 original 6v,new brilman harness,ign switch,amp gauge & volt regulator. had the generator tested and said it was ok. I installed all,polaized the system,with the tractor not running, cranked and nothing from the amp gauge.while tractor was running i again polarized it and the system started working, untill you switch off or real low rpm, the volt reg goes offline and wont come back on untill repolarizing it. That is whats going on hope this helps?

 

[buickanddeere]

The cutout in the regulator opens when the generator is at low rpms or when at rest.
It's normal for the ammeter to drop to zero ir - numbers are low rpms. The generator only charges from mid to full rpms.

 

[LH TURNER]

I understand that, but if the system is correct it will run without a battery. My system will polarize when running, at low rpm it kicks out, like it should but will never come back online.

 

[buickanddeere]

A Kettering spark ignition engine operated from an ordinary generator system without a battery. It will loose voltage as the rpms lower. To the point it will no longer fire the plugs.
Does this situation occur when a battery is connected to the system?
What do you mean by "polarize"?

 

[LH TURNER]

Fixed! the new voltage regulators(made in china)points were not set correctly. so if any one buys a new volt reg check it out before installation!

 

[Freddy]

Thats why I don't buy CHINESE

 

[buickanddeere]

Doesn't matter where they are made. They all require the cut-out to just cleanly open. When the generator/engine isn't turning.
A volt meter is required to set the field spring tension to 6.9V. Going via by guess and by golly looking at the ammeter is a "hillbilly" calibration.

 

[TURNER]

I didnt say I had to adjust the tension,just adjust the contact it was not mating correctly. By the way dont you know what polarize means? Also "made in china" does matter,first price, second out of all the volt reg I have installed I never had a problem with one made by STANDARD. I guess it takes a couple hillbillys,rednecks& yanks to make the world go around!

 

[buickanddeere]

This sounds like setting spring pressure, not bending the contacts to line up.

Quote"points were not set correctly." Unquote.

Just to be certain "polarize means what ? I've seen the same term used for different situations.