The problem I was trying to solve was that I couldn't move the alternator back from the rear of the car and it caused the alignment with the crank pulley to be off by nearly 1/2 inch. The fan backing plate tin protruded out too far to allow adjustment.

After looking here, thesamba, shoptalk, etc, I bought the CB Performance crankshaft shim kit. It took all of the shims and more to get close.

While I could align the pulleys, the crank pulley was pushed so far out, it only had partial contact with the woodruff key. So, back to the drawing board.

I checked the source of the fan backing plate and shroud. The shroud was an EMPI product as was the backing plate kit.

Checking around for potential high quality replacements, I saw that Awesome Powdercoat uses SCAT shrouds and the same EMPI backing plate kit that I used.

So, it's probably just a Chinese copy doghouse shroud that isn't well made. I double checked the shroud installation and it was dead centered on the mounting screws and oil cooler. There was no room for adjustment.

So, besides springing for a new, high quality shroud, what could I do? I decided before placing an order, I'd take the big hammer to the backing plate kit.

Using a 2x4 and my big hammer, I shaped the contact points between the two plates so the alternator side plate could move into the shroud. I then used my thumbs to press the middle of the alternator side plate into a more concave shape. I then put the plates together and banged on the middle until the plates touched. 

Problem solved. The alternator sits back on the stand much better and can be pulled slightly towards the rear of the car to align perfectly with the crank pulley with no shims installed on either pulley. I had to slightly enlarge one of the alternator backing plate screw holes and one of the backing plate to shroud screw holes for an easy fit.

Final alignment steps:

1) Install shroud on the engine

2) Place the alternator stand on studs (don't tighten yet)

3) Place alternator/fan assembly on stand and into shroud. Loosely attach backing plate mounting screws

4) Push alternator stand towards shroud and tighten mounting nuts

5) Push alternator towards shroud until pulleys are aligned and tighten the alternator clamp to the stand tightly to hold it in alignment

6) Tighten the backing plate mounting screws to seal the plate against the shroud

I know this is a simple, brute force solution, but it works and could save a few alternator belts.

MikeIMG_20200408_114644IMG_20200408_114739 

Mike Pickett

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I have the same problem with the alternator sitting too far aft. So this must be a common issue. The center plate seems like the cause of the problem. One that should be easier to resolve than using a hammer

I tried installing an aftermarket aluminum pulley with degree marks on it. But, as with you, it needed too many shims and was unstable. The only pulley that worked was a stock OEM steel pulley, but it needed 2.4 mm worth of shims.  

My alternator mounts on the stand as in the picture. Too far aft. Yet, I've seen other engines the same way, with similar looking center plates and using aluminum pulleys. 

So much of the aftermarket stuff is pure crap. I just spent the afternoon cutting and hammering some tin on my new engine so it would fit. 

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