YM 2000 new regulator smoking

[Gary2]

I have a YM 2000 and the battery was slowly loosing charge. The alternator tested bad at the parts store so I replaced both the alternator and regulator with NAPA parts listed for a 1972 Datsun 510 (12V 50A). I found the Datsun part crossover in this forum. Both parts were almost identical to the original except three of the six regulator wires at the connector were a different color code.

After running the engine for about 1 minute, I noticed smoke around the back side of the regulator, I turned the ignition to off but kept the engine running for another minute and the smoke disappeared. I checked all the connections and the battery ground to the frame and every thing seemed ok. I cranked the engine again and the same thing happened so I shut it down.

Before running, the battery was charged to ~ 12.8 V. During the first minute of the first run the battery was charging at ~ 13.8 V. I plan to call NAPA on Monday to double check the part numbers. Also, I did not purchase the 1973 regulator for the 1972 alternator as suggested in this forum, I purchased a 1972 regulator & alternator. Would this make a difference?Does anybody have suggestions, any help would be greatly appreciated, thanks Gary.

 

[Soundguy]

How much smoke?

Some regulators have a biasing resistor on them.. this may flash a'little' smoke off... however.. justa a little.. not a lot.

Got to be carefull about electronics.. you know.. they run on smoke. Once you let it out.. they stop running.

Double check your connections. what's ammeter and voltmeter show during running?

( I added a hitachi alternator and old style chrysler reg to my 1700.. worked great.. )

Soundguy

 

[Gary2]

Soundguy:

Thanks for the reply. Last night I removed the regulator and found that one of two wound coil looking parts had darkened and had a smell like somebody let the smoke out. I think these might be the biasing resistors that you were talking about. This afternoon I reinstalled the regulator, connected an old analog volt meter to the battery and cranked the engine again. That let a little more smoke out but, it stopped in a few minutes. The volt meter indicates 14 V at 1500 rpm and 14.8 to 15.2 V at 2300 rpm where the red dot is for the PTO. I ran the engine for about 0.3 meter hours at varying rpm and everything seems fine. The areas on the regulator next to the two coils get hot but, all other parts (wires, connectors, and alternator) are at normal temperature. Looks like I am ready for some mowing if the rains let up. Thanks for your help and all the other post you have made. This is a great forum and a great place to learn, Gary.

 

[Soundguy]

The biasing resistor's I'm talking about are usually thin and long, and have a single coil of wire wrapped around them end to end.. usually over some sort of heat proof substraight.

In any case.. if it is working and not smoking anymore.. I'd just watch it...and see what it does. Your are already in it for the cost.. might as well set for the ride.

Soundguy

 

[normde2001]

Gary, in you original post, you said the alternator tested bad at the parts store, which could very well mean that your old regulator is still good. I would try the old one and compare voltage readings. Your output with this regulator sounds a little on the high side to me.