Howdy folks!
Been a crazy few weeks of trial and error but I wanted to start a thread explaining how I got the 90amp alternator upgrade to work in my 91’ FJ80 without the typical grind and force to fit with the factory 80amp bracket method that so widely seems to be the only answer. Today I’d like to share my method that I have yet to see ever been done (or at least documented here) Although this solution is uncommon it may work for a lot of folks who are having issues getting a solid 80amp and may have a dead 80amp laying around that has the parts needed to make this new method work.
So low and behold I found myself in the predicament that many early FJ80 owners have been through and have unfortunately suffered the same fate when it comes to alternators going bad. Roughly 4 weeks ago I noticed my 80 took a while to crank up early in the morning and didn’t think much of until later that day i filled up with gas and bam, battery voltage dropped enough to not start the vehicle. At first I figured the battery had started to decline but of course after happening a handful of times it was apparent the alternator would no longer charge the battery.
Without much thought i decided to find a replacement online for my bad alternator which lead me to purchasing a 90amp factory Toyota replacement from the folks at Cruiser Teq (highly recommend them if your looking for anything for your Land Cruiser!) upon purchase i thought this would be a straight forward swap but after removing all the belts and pulling my old unit out i realized immediately that the 90amp alternator was different and would not mount up to the existing bracket due to the mounting ears being much more narrow than the factory 80amp alternator. initially i was under the impression that Cruiser Teq sold me the incorrect unit so i contacted and they replied assuring me that the 90amp is a factory upgrade but requires a different mounting bracket for it to work (they prompt this on the product, i simply overlooked and bought without researching)
Being the great business that Cruiser Teq is they offered to swap out with the factory 80amp at no additional cost but i was curious to see if i could get it work as an upgraded unit sounded like the direction i wanted go. This is where issues started to begin. I figured that all i would need for this swap was a 90amp alternator bracket and i would be good to go but after some googling and sourcing part numbers it was more than apparent that this bracket was more than rare and almost impossible to find. This lead to searching many threads on Mud just to realize nobody has actually swapped in a 90amp with the factory bracket. Even with correlating part numbers most parts distributors (Partsouq, Amamyama, Toyota, etc) either listed incorrect brackets as subs or just stated that the part was discontinued (i learned this the hard way purchasing two different brackets that were subbed under the original part number)
Below is an image i got off mud under an existing thread that shows part numbers and visually why the 90amp alternator doesn't fit ( apologies for no credit i will find the OP and credit) i also am including images that show measurements of both mounting ears so you can see that there is a significant difference.
Diagram showing the mounting difference, P/N’s, and measurements.
80amp ear measurements (mm)
90amp measurements (mm)
80amp ND with internal fan on the left, 90amp upgrade on the right. Quite different in terms of mounting
Top view
Been a crazy few weeks of trial and error but I wanted to start a thread explaining how I got the 90amp alternator upgrade to work in my 91’ FJ80 without the typical grind and force to fit with the factory 80amp bracket method that so widely seems to be the only answer. Today I’d like to share my method that I have yet to see ever been done (or at least documented here) Although this solution is uncommon it may work for a lot of folks who are having issues getting a solid 80amp and may have a dead 80amp laying around that has the parts needed to make this new method work.
So low and behold I found myself in the predicament that many early FJ80 owners have been through and have unfortunately suffered the same fate when it comes to alternators going bad. Roughly 4 weeks ago I noticed my 80 took a while to crank up early in the morning and didn’t think much of until later that day i filled up with gas and bam, battery voltage dropped enough to not start the vehicle. At first I figured the battery had started to decline but of course after happening a handful of times it was apparent the alternator would no longer charge the battery.
Without much thought i decided to find a replacement online for my bad alternator which lead me to purchasing a 90amp factory Toyota replacement from the folks at Cruiser Teq (highly recommend them if your looking for anything for your Land Cruiser!) upon purchase i thought this would be a straight forward swap but after removing all the belts and pulling my old unit out i realized immediately that the 90amp alternator was different and would not mount up to the existing bracket due to the mounting ears being much more narrow than the factory 80amp alternator. initially i was under the impression that Cruiser Teq sold me the incorrect unit so i contacted and they replied assuring me that the 90amp is a factory upgrade but requires a different mounting bracket for it to work (they prompt this on the product, i simply overlooked and bought without researching)
Being the great business that Cruiser Teq is they offered to swap out with the factory 80amp at no additional cost but i was curious to see if i could get it work as an upgraded unit sounded like the direction i wanted go. This is where issues started to begin. I figured that all i would need for this swap was a 90amp alternator bracket and i would be good to go but after some googling and sourcing part numbers it was more than apparent that this bracket was more than rare and almost impossible to find. This lead to searching many threads on Mud just to realize nobody has actually swapped in a 90amp with the factory bracket. Even with correlating part numbers most parts distributors (Partsouq, Amamyama, Toyota, etc) either listed incorrect brackets as subs or just stated that the part was discontinued (i learned this the hard way purchasing two different brackets that were subbed under the original part number)
Below is an image i got off mud under an existing thread that shows part numbers and visually why the 90amp alternator doesn't fit ( apologies for no credit i will find the OP and credit) i also am including images that show measurements of both mounting ears so you can see that there is a significant difference.
Diagram showing the mounting difference, P/N’s, and measurements.
80amp ear measurements (mm)
90amp measurements (mm)
80amp ND with internal fan on the left, 90amp upgrade on the right. Quite different in terms of mounting
Top view
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