3G alternator bracket mod for 2.3

[RustBucket]

Anyone who's done or is looking to do the 3G swap might benefit from this little trick. When I did my swap, I bought a 130amp alternator for a '94 Mustang GT. Other than the obvious differences in case size, the mounting hole on the top side of the alternator is not tapped like the original alternator. Most of the swap articles suggest using a 3/8" bolt to attach the alternator to the upper mount. Sure it fits, but the hole in the alternator bracket is large by huge compared to the bolt even though it's a perfect fit for the alternator. The head of the bolt doesn't cover the hole unless you center it directly in the hole. That's a pain in the tail. Yeah, you could throw a washer on the bolt to give it more surface area, but that doesn't do anything about the actual hole size. I found a solution that's cheap and works great and only takes a few minutes to do whether the bracket is on the car or off. I did mine while the bracket was on the car, but the pics were taken while doing a spare I had in the garage just to show how it was done.

Here's the bracket in question. It's the one bolted to the head and holds the upper mount for the alternator

 

[RustBucket]

Here you can see what I'm talking about with the 3/8" bolt and the original hole. Reminds me of that girl back in high school.... nevermind

 

[RustBucket]

Here's the solution to the problem. It's a 1/4" galvanized pipe nipple. I used a 1/4" by 2" nipple to do mine. It fits into the hole and only needs a little effort with a pipe wrench or channel locks to thread itself the rest of the way into the hole.

 

[RustBucket]

This one was a looser fit than the one on my car so I ran it in a little further. You can stop when the nipple is flush with the backside of the bracket to keep from having to dress the backside down as I did here.

 

[Shinlee]

what did you do...? all i see is the problem is shown, but not the solution or am i just missing it and its a secret message i have to decode to understand, lol?

 

[RustBucket]

Patience grasshopper

 

[Shinlee]

bah sry, you apparently are typing this at the same time i am reading it, and while i only saw the top 2 parts, you typed 2 more after that while i was bitching, nm

 

[Shinlee]

I SEE NO PICS ON THE SOLUTION POSTS!!!! im GOING insane!

 

[RustBucket]

I must have numbered the pics wrong. The previous post shows the front side of the bracket. Here's the backside, all cleaned up and ready for the next step.

 

[RustBucket]

Our new solution has presented a small problem. The I.D. of the pipe nipple is now SMALLER than our bolt. We went from too big to too small. Never fear!! DeWalt is here, complete with a 25/64" drill bit to fix our new found problem.

 

[RustBucket]

All finished and ready to go. The bolt fits much better and is centered. Problem solved!

 

[RustBucket]

I'm done, you can bitch now Shinlee.:Zip2:

 

[glowstang93]

Rustbucket, I tried the 94 3g 139 amp alternator, but the case was way too big for the 93 bracket. The end to end dimension was good, but the case round was too big to allow it to meet the top bracket. Maybe 91 was different than 92-93. Here are some pictures of why it wouldn't fit.

View attachment 430024

View attachment 430026

View attachment 430028

Here is one of my 95 amp that is used on a 92 E-150 w/o ac.

View attachment 430030

 

[RustBucket]

You've got to clearance the bottom bracket a little to get the case to fit. I ground some out and actually cut a small piece out of the way. The mod I did for the upper bracket saved me from removing more material than I had to by picking the alternator up a little.

If I feel froggy tonight when I get home, I'll open the hood and move the alternator out of the way and snap a few shots so you can see what I did to the lower bracket to get the big case alternator to fit.

I'll warn you ahead of time, my engine bay ain't nowhere near as clean as yours so any pics I take may shock you

 

[glowstang93]

Yea, I was thinking that a mod to the top bracket would be an idea, but wasn't sure if the belt length would remain stock or not. Its ok, I won't say anything about a little dirt, I would love to see how you made it work.

I was wanting the 130, but really the 95 does a good job. I have had it for 4 years now and this new one is doing a great job of keeping volts up.

Thanks Rustbucket

 

[RustBucket]

Here's what the bracket looks like after modification. I did it in true trial and error fashion. Grind a little, check the fit, grind a little, check the fit. I cleaned it up a little, and I'll do more when that bracket gets transferred over to the turbo motor.

 

[RustBucket]

Here's another shot. I ran out of attachment space so I had to host it off-site.

 

[glowstang93]

what about the top hole? what did you do to it?

 

[RustBucket]

The top hole is what started this thread

If you clearance the bottom bracket, it will allow the alternator to rotate counter-clockwise more and line up with the other mount.