Where are the numbers stamped in to an engine? So I can match them to the firewall plate. and is there a place to check these numbers to find out the engine model. the plate says 12A but the engine looks smaller than the one in my 85 the rotor housings are 6CM thick . It is in a 1974 RX3 Rotary wagon. Thank you for all the help in the past. The old fart.

 

Hi!

The engine number on 12A`s are stamped near the dizzy.Its on the front Plate,in between the alternator,and the dizzy.On other engines i`am not so sure

Karis

 

I don't get it. Are you trying to ascertain if the engine is the original engine, or just trying to make sure it's a 12A?

All 12A rotor housings are 60mm wide.... and they all say "12A" on the top, on the distributor/oil filler/oil filter side of the engine.

 

PJ I dont know what the heck I have. As noted above is what I have and under dirty old RX3 in other rotary as well . It has me stumped. the darn thing looks small but the tag says 12A ??????

 

if its a 73 or earlier engine it wont have mazda cast into it in the normal spot. the 68-73 engines have twin distributors and are very different from the 74-85 style. if it looks smaller maybe you have a 10a in which case please send it to

mike c/o crazy ralph
920 west capitol expressway
san jose ca 95136

thanks!

 

But he said the rotors are 60mm wide... which makes it a 12A.

I have first dibs on a 10A being as I am physically closer. While 10As were available in RX-2s and RX-3s in other markets, the only 10As in US-market cars were in R100s, and production ended in '73 anyway. Plus they have 50mm wide rotors/rotor housings.

 

yeah but theres been 30years to do all kinda of dumb swaps. my r100 had a 73 12a placed in the engine bay, it ran but it really wasnt bolted down!

 

The 10A is 60mm wide, you crack smoker!

 

This is the way I thought it went:

10A=60MM
12A=70MM
13B=80MM

I could be wrong, but I remember reading that somewhere.

 

I dont do milimeters , but my fractional measure was 6Cm when converted from2480 plus/or minus a few. but surely not 7
thats why I want to find the numbers stamped in the engine to see if they mach the firewall plate. then contact Mazda and find out what the hell it is. Jeeze the things I get involved in !!!

 

LoL, 10mm=1cm, so 6cm=60mm

 

you think your closer, ha!

 

but i actually have an r100! i NEED it, if its a 10a, i already have a 12a

 

PeeJay, RX2's never had 10a's only R100's and RX3's.

So did you work out what motor you have?

 

still dont know what it is , only one distributor, Mazda no number cast into each rotor,nikki carb, oilcooler like 12a, had points in dist and it is short not like 112a , factory set up for cold weather start, cause it was delivered new in Alaska, But the good news is that it will roll over free with a small screwdriver. also the starter is on the left bottom like a 12a ????????????

 

If the housings say 12a, then it's a 12a.

 

Measure rotor housing length. 70mm = 12A.

 

the pre 73 motors dont have anything cast into them, they do not say 12a or 10a on them