1973 datsun 620 alternator

[FatDatSun]

Just did my alternator upgrade in the 73, it does have the l20b in it.

 

But moving forward.

 

It had the 35 amp alternator in it.

 

Swapped in a 1994 subaru loyal sl, the single pulley option.

You have to grind off one of the lower mounting tabs, (there is only one)

You have to bore out the lower mounting bracket i.d. hole as well to fit the mounting bolts.

You have to replace the upper mounting bolt with a bolt, washer and lock nut. But the arm can be used.

The original belt can be used.

The wiring must be done. The "T connector" 

Yellow will go to top of the T and the white/ blue is the lower half of the T (the one going verticle) on the stock it was reversed. 

Then at the external reg, connect red/white with black/white and connect white with yellow. There is a second yellow, the yellow white, ignore that one. 

 

If this was done exactly you'll have a running 60 amp upgrade alternator.

If not don't like this, your problem will be a bad alt or your wiring is shit. Or in the other case, my wires were shit but I narrowed it down. 

 

 

Goodluck, I feel this was pretty accurate.

 

 

Edited August 29, 2021 by FatDatSun

[datzenmike]

What about your choke heater relay coil that is now permanently wired on? The White wire places 12v onto the Yellow wire that also powers the choke heater relay coil. With the ignition off there is no power to the choke heater but the coil remains energized. It's not a lot but it adds up over time and runs the battery down. Till I fixed this the battery is low Monday morning from the draw for two days, and just barely starts. A three day weekend or cold weather I doubt it will.

 

BTW, nice write up and another option for more alternator power.