Charging System update for a '73
 

I recently put a 13B-RE Cosmo engine in my RX3. I am using the alternator from this engine and noticed a small problem. When I turn the car off I get a 1Amp drain on my battery through the charge wire. I tried to put a diode inline, but it started to smoke after a minute so I took it off. Has anyone else solved this problem?

Problem solved.

I have a 74 rx2 with the cosmo engine and alternator the generator light is on and I have to rev about 2500 rpm and the car starts charging. How do I fix this

sounds like alternator is dicked and needs re bushing!!

how'd you solve it 13BT? I think mine does something similar, the batt. in my RX-3 is completely dead after about a week of sitting.

Mike

Wackyracer gave me this link to an archieved thread.

https://www.rx7club.com/1st-gen-archive-71/electrical-s5-89-alternator-install-into-1st-gen-528440/

The problem was that I had keyed power to the "S" connection, but the Cosmo alternator required continuous power. I made the change and tested it with perfect results.

in my rx2 i dont have anything connected to the S and it works but like rex3 said i also have to rev it to about 2000 to 2500 to get it to start charging other than that it works fine.
guess i could fix it right some day now that i know what to do:)

Hmm, that might explain why my alt. also doesn't kick in until I drive the car around a bit. The previous owner did some odd wiring under the hood that I haven't been able to figure out yet.

Mike

Thats typical for single wire alternators.
My Chevy 1 wire alternator does it every time.