So i was searching the net, like allways, and a ad caught my eye.. Mazda 1000A engine for sale.. Thats weird i thought, an called the guy.. The engine was indeed a 10A, that actually ran when it came out of the Capella it had been sitting in. Got it dirt cheap, so i bought it! This is what ended up on my doorstep..








Needless to say, i figured it was time for a rebuild!

Tore it down and found this, one rotor is late 70s and one early.. The early beeing the double side seal one..





Irons not to shabby..



Twin dizzy front cover!



RX3 special feature, three exhaust ports!

 

Well, i just had to reuild it, so this is what i bought:

- One used rotor, double side seal version
- 6 (!) mm one piece apex. I actually got a hold of these!
- All new seals, bearings and o-rings

Of course, i forgot that the bearings are narrower on the 10A, so i had to modify a set of 12A/13B bearings. Had them machined down to the correct width, and bored out the holes you can see in the picture below



During assembly of the rotor, i got me a surprise.. The side seals were way to short.. I now know that the seals mazdatrix sells are precut for 12A/13B.. The 10A`s groove is longer because of it beeing closer to the edge.. No problem, just had to delay assembly a couple of days..



Other than that, the engine came together like a charm! A special feat, that i actually dont know why Mazda stopped using, is a chain tensioner. See pic:



Just had to show you guys a pic of the 6mm versus 3mm..



And a pic of housings before and after cleaning:

 

Engine done!

Short block:



Complete, without oil pan and sump:



BTW, the orange cables are just there for show, its from a 12A turbo..

Front, still needs a little cleaning and new bolts, but almost done:



Original exhaust manifold..



Well, im done with it.. Now i just need a car to put it in!

 

Very rare find indeed!

Well done on the rebuilt,it looks good as new!

Karis

 

very nice find. very jealous of you right now. where are you sourcing these parts from?

 

Mazda actually stocks most of the items, everything except for apex related parts are the same as the RX7. The rotor and apexes came from a guy i know that has everything rotary related! Everething from early 80s Mazda CDI ignition, to dry sump front covers.. He actually drives a early Cosmo with a genuine 12A turbo, and is the man to call of you are in need of hard to get parts in Norway!

 

Nice buildup!

I never seen a 10A in person, especially the 3 port exhaust, Kool!!

 

Nice! I have a '71-'73 12A just waiting for a rebuild. I just don't have anything to put it in.

 

Wow.... those exaust ports!

Nice work!!! :thumbup:

 

very nice,

cool find

how do you get the housings so clean????

 

^looks like he media blasted them...maybe some high temp clearcoat too.


cool find, ive never seen a 10A's innerds before...more pics for me to add to my collection

 

Thanks for the comments guys. I glassbead blasted the housings, we are fortunate to have it at the shop! No clearcoat..

 

The surface won't stay looking like that for long.

 

I know.. Im currently stripping her down to shortblock for some more paint, as im not entirely happy with the finish.. The guy that was going to do the bolts/nuts is taking his own sweet time, ill post some pics when its all complete with rebuilt carb and "new" bolts

 

Okay, that is the coolest thing I've seen yet. Nice work on the clean up. What kind of car are you aiming to put it into?

 

What a rare and classic find. It's even more amazing that you found all the parts to do a full rebuild. Thanks for taking us back to the early days.

 

Yea, great job w/ the rebuild. Now let us hear this baby running! I've seen that tensioner part before in the old 74' 13b's. I also wonderd why they stopped using that tensioner piece!

 

have you not just destroyed those bearings by boring them over? it looks like you're into the copper at the joint. also do these bearings not have a babbit layer like a crank journal bearing? if so it's toast.

 

Gavin, the bearing looks a little weird, but I'm sure it will be fine as long as the clearance and oil pressure are good.

 

Hey nice insights men...

 

Mortenf, Great documentation of a 10A torn down and rebuilt...

Dwayne

Hey Jeff, My friend has some Spanking NEW early 12A housings for sale never installed from Mazda...

 

The picture is of the old bearing that i replaced, i just took the picture of it to show how it originaly looks.

 

Nice work, good to see a 10a being built. The 10a rotor bearings are available from Mazda, but for some reason under a different part number not in the books... have it somewhere if you get keen!

 

im also interested in this, is he local? i hope hes not an ******* like your other friend with the mint yellow rx2...im very interested, PM me details