90 Amp Alternator upgrade / mod thread (1 Viewer)

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A pillar grounds? Referring to the ones inside next to the fuse box?
 
A pillar grounds? Referring to the ones inside next to the fuse box?
Yeah, there is one on each A-pillar. One on the drivers side up above the fuse box (its a pain to get to), and one on the passenger side that is much easier to get to. Both of these points are important ground locations for the OEM harness so cleaning them can only help in my opinion. Mine were a bit oxidized.

Edit: Great pics here Where are the FJ62 ground points?
 
Yeah, same with me. Adding the wire helps with charging the battery but has nothing to do with the OEM wire harness. Making sure you have good grounds and clean connections will help with the idle charge voltage at the meter.
That's what made the bigger difference for me. I added 1/0 cables to ground the block, cylinder head, body and alternator case. Voltage is much smoother overall and starts are way better.
 
I got the bracket milled at work. I bring it home and my calcs were off by .025”.

Right now the alternator is sitting on the back mount face and not the front which is where it should be to line up with the belts.

So how tight does the alternator and bracket need to fit?

Weighing my next move. Take back to work or install?

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Well if your not in a hurry just make it right.. then you will have the correct measurements for your thread .025 isn't much .25 is lol good stuff tho more options for all of us
 
I got the bracket milled at work. I bring it home and my calcs were off by .025”.

Right now the alternator is sitting on the back mount face and not the front which is where it should be to line up with the belts.

So how tight does the alternator and bracket need to fit?

Weighing my next move. Take back to work or install?

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Oh that is not fair! I had to do it with a Dremel! Hahaha.
Nice work! Looks great. I say go the rest of the way and make it contact. Then there is no side pressure on the arm so no risk of a crack forming over time. Although I bet that wouldn't happen anyways. :p
 
Anyone know how much axial runout is allowed between all the belts?

If the alternator pulley was .025” too far forward would it cause any issues? I’m guessing no.

No I need to look at it and determine if I can sand the spot down with a file on the rear lug or give up and take it back in for a haircut.
 
Lots of learning this evening. This thread will be the experiment and I’ll make a faq thread after.

The tensioner bracket is different. You can buy or mod as I have. The bolt that tightens the tensioner must be threaded longer with a die or buy a longer bolt.

The tensioner bracket can be extended 3/8” towards the back of the vehicle to accomodate the new alternator.

The 90A alternator has a thicker top third ear which means the tensioner bracket end where the bolt tightens must be modded.
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All buttoned up and working.

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Is there any chance that this, if done incorrectly or not, could cause the alternator's pulley to be slightly offset and make the belt whine?
 
Is there any chance that this, if done incorrectly or not, could cause the alternator's pulley to be slightly offset and make the belt whine?
The back part of the mount is what needs to get clearance, so the front mounting ear positioning doesn’t change. The pulley alignment shouldn’t get altered at all.
 
red66toy explained it well. The alignment of the belts is not modified when clearancing the rear lug of the engine mount.
 

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