GM Alt swap EA81 bracket mod

[ferox]

So after excessively grinding down the ears of a narrow case GM 7157 alternator to fit it on my stock ea81 alt. bracket I told myself next time I mod the bracket instead--with the idea that the modded bracket is a one time mod and allows for a roadside alt. replacement.

 

This is the narrow case alt. I am referring to, which is stocked at many auto parts stores

 

I basically cut off the rear face of the alt. bracket, removed some of the spacer material, and welded the face piece back on. Stock bracket width between the alt. ears is approximately 3.17"/79mm. The GM width between the ears is approx. 2.5"/63mm.

 

The only thing I would have done differently is to cut the, back face, off down further on the bracket (from position A to , so that the rear alt. ear would have more clearance and provide more adjustment for installing the belt. The way it is pictured, I still had to use a small round file to notch the rear alt. ear a little bit to get it to swing down a fraction more so I could get the belt over the pulley. Not a big deal, but my objective is roadside install, so once my shiny paint job wears off a bit I will grind the bracket down slightly. The other small bracket pushes the alt. position adjuster out one inch so that it lines up with the radius of the alt. pivot. BTW the long pivot bolt and captive nut bracket work perfectly with this set-up.

 

 

Here you can see that the one inch spacing provides minimal clearance with the alt. bracket. I filed a flat on the outer diameter of the bracket bolt washer so it wouldn't be under the alt. bracket. I have used this spacer set-up on my hatch for approximately a year and a half now with no problems.

 

A couple shots with the alt. installed. Belt size 15365 for both of the alt. swaps I have done. This belt size also makes the alt. fit under the stock air cleaner like it was made for it.

 

 

 

Thought I would throw in a shot of a factory crimp. For the '84 this is the alt. sensor wire (smaller white) and I am guessing FPCU? wire (blue) crimped to the alt. power wire (large white). This crimp is located about a foot back from the fusible link box...behind the battery. In my '81, the ignition wire was crimped in here and nothing else. On the '84, the ignition wire is actually factory crimped on the alt. side of the engine compartment, about two feet down the power supply wire from the alt. You have to dig into the harness for both. Unless you are replacing those wires, make sure they get hooked up to whatever alt. power wire you are running.

 

 

[Twitch de la Brat]

Here here! For a link to the USRM!!!

Anybody else up for that?

 

Twitch