Help me ID this 12A

I am trying to track down the right counter weight for this engine, but haven't been able to determine what year this is from the get the right one.

Not sure if I missed a serial number under the grime, so hints are appreciated!

Looks just like the 84 in my garage.

I am NOT a 12a genius.

I'm stumped. Do you want a front counterweight (which is matched to the engine already and shouldn't be changed), or are you planning on putting an automatic trans on the engine and need a rear counterweight? On a manual, the rear counterweight is part of the flywheel, if I recall correctly, so it only matters if you are changing the flywheel.

If it is for an automatic, Mazdatrix has a FAQ on them

I am betting if you call Mazdatrix, they could help. They also sell counterweights, and if you talk to them about your purchase before hand, if you get the wrong one they would probably not give you any sort of hassle with an exchange.

Atkins may also be able to help.

In reply to Brett_Murphy:

Thanks for the contacts! This is going in a Beetle, so the flywheel is part of the adapter. A rear counterweight is what I need.

You took photos of nothing really useful. The points distributor indicates it is before 1980, or at least the distributor is from before 1980.

What does the flywheel look like? If it is completely flat across the face, it's a pre-1983 engine. I think all 12A engines from '74 to '82 have the same rotor weight and thus take the same counterweight.

Pull all the junk out of the ports and take in-focus photos of the ports side of the engine. Of critical importance is what the exhaust ports face of the engine looks like.

Really just a picture of the business end of the flywheel is probably enough to narrow it down to what rear counterweight you will need. The problem is, I'm pretty sure all 12A rear counterweights are NLA and you're going to have to pay $$bank$$ to get a used one. I let one from an '82 go for $60 a couple years ago, now they seem to be going for $300 and up for used ones.

Knurled wrote: You took photos of nothing really useful.

This is what I like to hear! I am a total rotary rookie, so its good to know those are all very generic views.

I will go check out that flywheel.

Alrighty, dont have that MASSIVE socket lying around so the flywheel still on the engine. Thanks for the help folks!

Chris will drop in and probably be able to ID it.

Looks like the 78-79 ones I have both on a stand in my garage, and in my 78 production GS. I believe there are some distinguishing numbers on the rear iron behind the flywheel that will tell you exactly.

I have an automatic counter weight for a pre 82 (maybe 83 I don't remember the cutoff) engine. I used a light-weight steel flywheel in my 83 years ago, and it required the use of an automatic counter weight(came with it). If I can find it, and it's the right one I could probably be persuaded into selling it.

In reply to Mazdax605:

I heard George Washington can be quite persuasive.

I need to get the giant socket on order to pop that flywheel off.

Measure the mating surface of the clutch area on the flywheel. If it's 225mm it's a later engine. If it's 210mm(maybe 215mm I forget exactly) it's an early engine. Now that I'm thinking about it I think the counter weights fall in the 79-82 or 83-85 for the 12A's. Mine is probably the 83-85 as it was in my 83 LE back in the day. I sold the flywheel, but kept the counter weight.

Edit: Yours is definitely not an 83-85 just by the way the flywheel looks. Could be 79-80, or 81-82.

After some delays for tool purchasing and the discovery of missing engine mounts (my favorite surprise) I have the flywheel off!

There is a TX and a 2 on the back.

Sorry I missed the post. The pictures from the 19th are enough. Mazda only made one weight rotor from '76-82 and that flywheel is a 215mm flywheel, which is '82-earlier. (Flat face = 215mm. Raised pads for the pressure plate = 225mm) So you need a '76-82 rear counterweight.

Now you know the name of the unicorn that you must hunt down, at least!

Fortunately for you, the counterweight you need is still available: http://mazdatrix.com/getprice.asp?partnum=11-751A-1883

Knurled to the rescue!

Thanks a lot folks! Now to order parts!