1971 Alternator Question

[bbrinkley007]

The alternator on my 1971 FJ40 1F engine is at the extent of the adjustment on the mounting arm, yet the belt is looser than I would want. The belt is also contacting the adjustment arm very slightly, which is clearly not correct. My question is what is going on. I wouldn't be surprised at all that the wrong alternator was put on it (it is 54 years old) but also would imagine that isn't too unusual. Are there any recommendations on how to approach this? I was planning on just getting a shorter belt but the rubbing issue definitely need fixing. The alternator pulley has two grooves, but with battery location I am not sure if this alternator will work if I shimmed it to use the front pulley. I suppose it could be as simple as a shorter belt and moving the pulley forward on the shaft and re-secure. But, since there is so much knowledge and experience here, I thought I would put it to the experts. As always, thanks so much for any suggestions.

 

[charliemeyer007]

Move the shim on the bottom mounting bolt pic 2.

 

[Skreddy]

Looks like a GM “1 wire” style alternator? Any numbers on the alternator?

That belt looks a little ratty too….

 

[bbrinkley007]

Looks like a GM “1 wire” style alternator? Any numbers on the alternator?

That belt looks a little ratty too….

I can't find any identification on the alternator itself, but ChatGPT said it was a Delco Remy 10SI from photos I provided. How is this pertinent? Is it the wrong alternator for an FJ 1F engine for mounting purposes? And yes, the belt is ratty. Probably from scraping the mounting arm as I mentioned. I do plan on putting on new belt, but need to resolve the mounting question first, or whether a different alternator should be used. Thanks for your input.

 

[rlong]

Yes a common GM alternator “cobbled” on to your 1F; as such it is challenging for others to give you specific advice, most people have figure out how to make it work on a case by case basis, not some specific plan that I’ve seen (did this on two <64 FJxx’s to convert from generator). You should try Charlie's advice above. The double pulley likely won’t work with the rest of your pulleys.

 

[Skreddy]

It is not a Toyota alternator. Common GM alternator. Depending how modified the wiring is will determine whether it’s worth going back to Toyota or making that one work. You can get a single pulley and shim it slightly if needed.

 

[MDH33]

I would try to go back to stock alternator and location, which I think is lower driver side mount.

Here's my '69 F setup