Hi Folks, I'm sorting out my fan clutch collection and could use some expert help on figuring out which belongs to whom.

I'm sure this one (Fan clutch 1) is for the 84/85 12A, it came out of an 85 GS and I have about 5 more just like it recovered from my 84/85 GSLs over the years:





I'm guessing this one (Fan clutch 2) is from an 81-83 FB, or maybe an SA? It has the same diameter cooling fins, but a longer shaft and the mounting plate is circular and smaller, with unthreaded mounting holes that are spaced closer together. Also the plastic fan has notches in the rim, unlike the 83/84 unit.





I got Fan clutch 3 (below, on the left) as NOS on ebay. It matches the dimensions of the 83/84 12A unit (Fan clutch 1) and the mounting holes are spaced the same, although the shape of the mounting plate is circular (lower picture), not like the star shape on the stock 84/85 unit. So I'm guessing it's an aftermarket 84/85 12A fan clutch?

I don't know where Fan clutch 4 came from (below, on the right). The cooling fin diameter is 3-4 cm larger than Fans 1-3. The mounting holes and plate are the same as on the 84/85 12A unit (Fan clutch 1) and the length of the shaft is about the same as the 84/85 12A unit. I'm guessing it's for an SE or maybe an FC?





Any help sorting this out would be much appreciated!

(Note: Mazdatrix list three different part numbers for 79-85 12A's, and a fourth one for the SE)

http://www.mazdatrix.com/b9.htm

 

I knew that clutch fan from my SA would come in handy. I'll check later and let you know which
is the SA one.

 

#1 maybe SA
#2 might be FC as i have one and noticed the flange difference right away
#3 no idea. don't recognize that type flange
#4 i'd say FB

 

Just pulled off mine. Getting it down to 15 minutes on taking it out and sticking it back in...

I believe it's a match for your first one:

 

Sure does look like a 84/85 unit. That's good news, I got a bunch of those. Please send the mailing address. PS, nice looking air intake.

 

-the round flange fan clutch i believe is from an SA or 4 port 13B.

-the extended shaft flange on the clutch is from an FC

-keep in mind Ray that there are two different S3 fan clutch variations, with the SE fan clutch being slightly different. the shorter flange allowed Mazda to use the same water pump, radiator, fan, and shroud all while using the new EGI engine.

-the larger fan clutch with ears is from an 81-early 83

-the standard S3 fan is shown with the ears on the flange and the clutch mechanism is smaller in diameter than the S2 unit.

 

Thanks Michael, Dave and Taran, I think it's starting to sink in.

So this unit is for the S2 81-83 12A, right?





And this one is for the S3 84-85 12A:





And this is an aftermarket S3 84-85 12A unit:





And this one is uncertain, but probably from an earlier 12A:





Can anybody identify that last one?

 

Ray, the last one is from an FC as mentioned in my awkward post above, lol

 

Thanks Dave, I'm surprised, that one looked like the oldest one in the bunch.

Now I have another question. Are the S3 84/85 clutch and the S2 81-83 units interchangeable?

The mounting holes and flange is the same and they seem to have pretty much the same overall dimensions. The only differences seem to be that the S2 unit has 7 blades instead of 8 on the S3 and it has that extra ring of air vents around the outside of the clutch unit.

Also, Tim, if you're still listening, I'd be curious to see what one of those SA fan clutches look like!

Thanks

 

I've got some SA fan clutch pix I could post, Ray... but PhotoBucket says my account is "In Maintenance," and I can't get to them at the moment.

If memory serves, it has the 'cloverleaf' pattern mounting face (rather than round) and the fan blades are straight-edged.

 

I would like to see what the 79 looks like DD, just to complete the catalog and see what the interchange options are.

And I'm still guessing an 84/85 12A fan and clutch unit should install just fine on an 83, right folks? Maybe even considered an upgrade, since you get 8 fan blades instead of 7?

 

Account still in maintenance... sigh.

So long as the hole pattern, overall front-back distance, and fan diameter all match up, blade count shouldn't matter.

 

Alive again at last. 1980 SA fan clutch assembly:


I thought I had more pix of it posted to PB than that; I'm sure I have more but I guess they are just not uploaded.

Seven straight-cut blades. The clutch assembly details look very similar to the 81-83 12A below, with the through-vented front ribs, smaller-sized clover-leaf mounting hub, and ribbon-type bi-metal on the front.

 

I'm always amazed by your pictures and work DD, thanks for posting.

 

Thanks for the compliments, Ray.

Beauty tip for fans; removing them and scrubbing them with a pasty mix of OxyClean and water works wonders for getting the old grot and oxidation off. That same fan was yellowed and almost grey-black on the faces and edges with 30+ years of dirt that nothing else (including solvents and even paint stripper) would touch.

 

Good idea. :-) If you want to save some time with the OxyClean, use a polishing attachment on a Dremel. I'll snag some Oxyclean tomorrow when I'm picking up more sandpaper...

 

DD, I won't be satisfied with my current FB project if the fan and fan clutch doesn't look as good as yours, thanks for the tips.

I've always used Comet or Ajax scouring powder, the stuff with the bleach, along with one of those green Scotch Brite pads to clean up the fan. But I have to admit they don't come out as clean as the one in your picture.

So, as it seems to be with most things in the evolution of the FB from 1979 until 1985, the fan clutch got a little better each year, flat blades replaced by curved blades, 7 blades replace by 8, culminating in the 84/85 unit.

 

Found a before pic of the fan:



That's after aggressive scrubbing and soaking in bleach.

 

Oxiclean. That stuff's mean.

 

Yeah - you DO want to avoid Chlorine and plastics; it's a bad mix. Without launching into organic chemistry... it chlorine makes most plastics and rubbers brittle. Does not play well with others. :P

And - yeah, oxiclean. For even finer touchup, a Magic Eraser is always good to have around...

(My ACV blockoff is here, w00t. Time to go play)