I've got a dual belt pulley specifically for FD alts being put on FCs. Apparently they are no longer being made.

 

how much do you want for it? lol

 

i've looked all over for that damn pulley. i can't find anyone who has it. do you have any ideas a dual v belt setup that has a 3rd gen diameter? as far as oem pulleys go?

 

Something to think about: I don't know which pulleys you speak of, but a friend of mine made a pulley for his car (not a rotary), which he had anodized. For whatever reason, once the belts warmed up a bit they tended to slip no matter what he did so he took a bit of sandpaper and cleaned the anodiziation(sp?) off the contact areas of the pulley. That fixed his problem.

 

Here's a link to a thread with peeps looking for similar pulley setups.
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/rotary-innovation-dual-alt-pulley-800652/page4/

That's interesting. I'll need the alternator off for the water pump. Can't hurt to scuff up the pulley grooves.

 

Update...

I have water pump waiting to go on. I'm just waiting for the housing to get back from the machine shop. I had it tapped for a water temp gauge.

What I found alternator related is that my alternator inner most belt is wearing unevenly. The engine side of the inner most belt is frayed a bit and there is considerable amount of black dust under the alternator pulley from the belt wear.

I've never dealt with alts and water pumps going bad, but here are my best guesses:

1. the alt and pump are both bad or going bad, but unrelated to each other

2. so long as the pulley I bought was as advertised (made for FD alt going on an FC) it shouldn't be an alignment issue

3. with the uneven wear of the inner most belt I'm probably looking at the alternator shaft being out of alignment with the cause being bearings in the alternator

any help is always appreciated

Last thing, is Gotham still in business? After the robbery they were doing alt rebuilds, but I can no longer find their website. Did they close up shop or am I missing something obvious?

 

I can't see how the waterpump going bad could affect the alternator; if the wp is going bad, the seal would leak, the bearing might squeal or sieze, but until that point, the pulley on the wp pulley should run true.

This is an assumption based on trust of an aftermarket company making a non stock part, but I don't thing the pulley itself is the problem.
You may have over tightened the alternator trying to cure the squealing belts, causing bearing failure in the alternator. You can easily over-tighten a belt. Keep in mind the second pulley extends the shaft out further, giving additional leverage on the alternator shaft, increasing the side loading on those alternator bearings.

Look, the second alt belt is there to increase the contact area for the waterpump so that it doesn't slip when the air pump is removed. There is really NO need for the second pulley just to turn the alternator. SOMETHING is not rotating correctly or is in a bind. You are replacing the waterpump right now, so the only thing left is the alternator.

Why don't you try this:

1. Determine if the alternator bearings are good. If not, get them replaced at a regular alternator repair shop.
2. Have them put a standard pulley on the alternator.
3. Put the air pump with it's belt back on.
4. Sell the dual alt pulley for a profit.

I bet your troubles are over.


Done!

 

I bought the alternator used, if needed I have been looking into a replacement, rebuild, or remaned one...etc. Gotham was doing $150 rebuilds. Was going to put everything back together this weekend and see if the alternator and water pump behave differently/better.

The pulley got a decent amount of talk on these forums while they were still available and was bought from the same source as the other people who were happy with their purchase.

I was loosing coolant out of the weep hole of my water pump. I imagine the problems with both water pump and alternator could be overtightening the belts. I'm learning as I go, trying to improve my self-reliance...all that good stuff.

I don't have the airpump to go back to stock...didn't come with my engine. But my plan was to try each old belt as single belts till I find out if the alternator is bad. Test the deflection on them to see if they are in spec. Though I have to look in the FSM to see what spec is. Use single belts till I'm sure water pump and alternator problems are fixed.

Thanks for your help, user error might be as much at fault if not more than parts failure. Simply trying not to repeat any mistakes I'm making. You confirmed much of what I was thinking.

 

I finally picked up a reman'd alt., voltage is much better, but still not great. It never gets as a low as 12 so that's a step in the right direction