So i read all the forum posts on replacing the stock altternator and i have swapped them out on a couple jeeps i owned.
Thinking it would be a slam dunk i ordered up a Mechman 320amp alternator that idles about where the stock maxs.

Anyway...the 1st challenge was the socket i owned had too many "angles" for the five sided main bolt heads and nearly stripped the top one.
Picked up a 5 sided 14mm socket from Napa and both the main bolts popped right out.

Thinking i was done i reached in and discovered the alternator wasnt coming out.

Reviewing the documentation, googling, etc...all indicated those bolts should have been all that was holding it in.

Finally i logged into Toyotas site, paid $15 and began scouring the technical manuals.

Turns out there is a small bracket behind the alternator that attaches it to the block,.

My question is: Has anyone got a method for detaching the alternator from this bracket?
My hands dont fit back there and i can barely see the 10mm nut.

2007 is350

 

Finally got the bracket off after removing the air conditioner to gain access to the bracket.

Spent a day trying to get to the bracket.
Next day spent 90 min removing the AC...15 min removing bracket...15 min installing new alternator...90 reattaching AC...done.

Had i stepped back and thought about the 1st day i would have finished the 1st day.

Thanks JPBACKES for the post.

 

You're welcome

 

OK. HERE is how you get that bracket bolt off the engine side (engine stud).

So, the bolt holding bracket to engine is 12mm (whereas the bolt holding bracket to alternator is reportedly 10mm). But if you do not have a 12mm socket, then a 1/2" hex socket will work (at least my bolt was loose enough already to come off without stripping). However, the engine stud that the bolt is bolted onto is fairly long, so try not to have too much of a shallow socket (one trick is to TAPE the socket onto the end of the extension, instead of putting it all the way on over the ball-bearing lock, where it is ON JUST ENOUGH to be able to use).

So, I used two 3" extenders -- and trust me, it works better than one 6" extender, because when you sink a 3" extender into the other 3" extender, it actually comes out to be 5.5" total, giving you a half inch extra play room compared to the 6" one-piece extender; and you most definitely will need this extra room since the wratchet will hit driver side wheel-well.

OK, so, from driver side of engine, use a flashlight to get line-of-sight to the bolt and stud behind the alternator. You CAN see it. It IS possible. I will try to get a good pic uploaded. Now, drop your L-shaped wratchet-with-two-3"-extenders-and-12mm-or-1/2"-hex-socket tool down between the engine and car body just over the exhaust manifold, then you will guide your L-shaped tool around the exhaust manifold, with socket leading the way, till you get it angle in, then dock with the bolt! Then turn and loosen, but you most likely won't be able to drive it all the way off as to where the bolt sticks inside the socket. So, when it's loose enough and stops driving, get the 6" extender (yes, the benched player steps in to save the game), and put the socket on it, but instead of using the wratchet just use your hand and manually turn the extender to take off the bolt. NOW, CAUTION: The bolt may still drop, so be careful. In MY case, it didn't seem to want to stick to the socket; so what I did was left it on threaded on just one or two threads at the end of the stud, and then I reached in with my bare hand (and this can be difficult to get all the way to the bolt because you have to crouch down and stick your whole arm down between the engine and body, so it depends on your arm & hand size (and height )). Anyway, if you are able to use your hand, be sure to 3-finger it (with your INDEX, MIDDLE & RING fingers, not thumb). It's such a tight space, you most likely won't be able to use your thumb, so use your middle three fingers, and, LIKE A TRIPOD, unscrew the bolt slowly until it's off, carefully maintaining a clamp on it with your 3 fingers, then extract your arm & hand carefully out. Thing is, if you drop the bolt, it'll be very difficult to find with all the under-pans and A-frame and such, etc. Anyway, glad I got that out of the way.

Good luck!

 

Above was SUPER helpful. We just replaced our alternator at 130,000 miles and 16 years. Electrical fire smell on right of engine bay, battery wouldn't charge, and all gauges were going wild. Agree, you can just barely see it when in place. Take a trouble light and shine from the front side of the alternator and through the crack between it and the engine block. Move yourself to the drive side fender and get your head down at the top edge. Look between the wires and the bolt sticking up. You can only see the bolt with one eye and only in the exact right spot. You can move back forth to see either the exhaust bolt (higher upper right) and then lower left is the nasty alternator bracket bolt. To get it out we used a 12mm deep socket, 3" extension, and a 3/8 breaker bar. It was really rusted on. That engineer hopefully was fired after that stupid design.

 

I’m just wondering if the bracket is needed and what is it for?
im not sure if it’s been touched before but every bolt came off no problem but when it can to take the bracket off that nut is not coming off. Can that bracket be cut in half with a small long hack saw and is that bracket needed if so what for ? If needed then I won’t try to cut off

 

Toyota's engineers put it there for a reason, it's a support bracket so they likely felt the two studs wasn't enough. I'd suggest reading through this alternator DIY for the IS: https://www.clublexus.com/forums/is-...r-removal.html

iirc, it's a 12mm bolt. Use a 12mm deep socket and a few extensions (3-4in). Taking it out is much easier than putting it back in, would highly suggest taping the sockets/extensions together.

 

what is the bolt that you took off the old alternator used for? Is it necessary? Because I already swapped my alternator and didn’t take that part off the old one 😭

 

I dropped the nut that holds the bracket does anyone know what size it is so I can get another? I know it’s a 12mm bolt head but what about the threading size?

 

https://www.clublexus.com/forums/is-...-12mm-nut.html

 

You do not need to remove the ac unit. Take out ecu and ecu box. Then take a 12mm deep socket and 3 inch extension on your ratchet. You'll then put the ratchet down where the ecu box was and feed it through to the bottom of the headers/back of the alternator. It is a very tight fit, but get your wrench in under the ac line and then use your other hand to guide the socket onto the nut. I personally couldn't get anything bigger than 3/8ths in there and couldn't get it to spin at first. Grabbed a jack handle and used it as a cheater bar on the end of socket wrench to gain leverage. Then just ratchet it off and try not to drop the nut. That nut gave me hell, hope this helps