Bosch AL45X Alternator

[lawddf]

I currently have a Bosch AL45X alternator on my 73tii. Sometimes when I start the car the voltmeter stays around 12 volts, then eventually the alternator will wake up and raise the voltage to approximately 14 volts. Sometimes I have to rev the engine to get the alternator to charge. The fan belt is tight and not slipping and I added a ground wire from the alternator to the chassis ground which did not make a difference.

 

1) I've looked for a replacement AL45X but they all seem to be out of stock or NLA. Is there a similar alternator that is available for a reasonable price that will bolt up in place of the AL45X without significant mods?

 

2) Should I try replacing the voltage regulator and if so where do I get one?

 

 

[tech71]

First check and clean voltage regulator ground points, remove screws holding voltage regulator to inner fender, clean where they mate up with a wire brush/bit of sandpaper. Clean the blade connectors as well.

 You sure alternator is properly grounded to the engine with at least a 12GA wire (10 GA is better) and engine is properly grounded to chassis? Dont just look at them and say "looks good" Clean them!😉

There is probably an alternator/starter repair shop around your area, oft times a rather scruffy old building staffed by an equally scruffy/gruffy old geezer. They can test/repair your alternator. Might be nothing more than worn brushes,

Edited October 4, 2022 by tech71

[bergie33]

I went with a rebuilt AL41x.  It is from an E12 5-series or an early 6-series.  Seemed to be an easier fit for a Tii than many other upgrades.  Not a huge amperage upgrade, but at 65 amps, it is almost 50% more.