I'm relatively new to the rotary scene. I currently have an opportunity to pick up a complete 12a (Oil Cooler, clutch, intake, carb, etc.) for $200 bucks. It supposedly has 70,000 miles on it, but that cannot be verified. Is this a good deal? It's a two hour drive away so I'm on the fence. Any thoughts or tips?

I don't have an immediate need for a second engine, but I thought it might be fun to tear down and possibly rebuild and/or street port.

EDIT: BTW, I have a 1982 GSL with the 12a and about 118,000 miles.

 

It's hard to say if it a good deal or not without taking it apart. If the carb looks fairly clean, that might be a $50-$100 item. Post some pictures of the engine with the blue air intake off.

 

This is the picture from the ad. It's all I have.

 

Those oil lines MIGHT be the Racing Beat ones. This is not a bad deal. If the rotor housing are good it will make it all worth it. Right now, I see close to $200 in value. The oil coolor and lines might get you $100-$125 if sold. The complete carb maybe $50.

This MIGHT be a 1979/1980 engine.

Remember - the engine was pulled for a reason. Go into it thinking the engine is not good.

 

There are cheap $20 borescopes that plug into your phone.
I recommend getting one to look into the spark plug holes, intake, and exhaust.

 

I actually have one of those cheapo bore scopes. Okay, so seller confirms it's a 1979. What issues will I run into if I were to attempt to put this in an 82? I did some searching and it looks like there is an exhaust difference. I currently have the RB stainless headers on my 12a.

 

You'll be fine with the 1979. I don't see any major issues with the RB exhaust you have. You will want the 1979 Flywheel. This chart explains which year/flywheels match. The 1982 has the lightest stock flywheel so you'll be giving up that advantage.

https://www.mazdatrix.com/faq/flywheel.htm

 

Thank you for all the help on this one. I think I'm gonna pull the trigger, assuming it looks good in person. It seems like a relatively cheap way to get into rotary rebuilding. And since I already have a solid running car, I can take my time and be methodical about it.

One last question though. Is there any difference in port size between the various 12a years? I did some searching on this forum and nopistons and couldn't find much, but it seems my googlefu has been failing me today.

 

The intake on the 1979 might be a little bigger. I'm not an expert on the port size but we have people here that are.

 

Having a spare engine on a stand in your garage is a huge benefit, and at $200, well worth the drive. I bought a SE 13b from a forum member here who was doing a turbo2 swap into his SE and kept that engine on a stand for almost 12yrs before installing it and its the heartbeat of my 7 for the past 8k miles. Had I not found that engine so long ago, it would have turned a simple swap into scrounging for parts and the expertise to rebuild the one I have which is a lot more downtime.

now with the original engine on the stand, I can rebuild at my leisure and still have a spare immediately accessible. Go for it as I doubt youll regret it,

 

I like the cut of your jib and I think I'll take it to heart. I have room and time to have an engine on the stand, so I gotta do it!

 

Your good to go and thats not a bad deal.

 

Safely home with an extra 12a. I also got a 5 speed transmission and a bunch of misc parts thrown it. Today was a good day!

 

Is the 5 speed from the 1979?

 

I ended up getting a slightly different engine than the one pictured above. This one came from an 81-82 and I'm pretty sure that the transmission is from that same era.

 

Those carbs and oil cooler with lines are worth $200 alone! I'd say you scored pretty well on the deal. Even if you tear the engine down and part it out you'll make your money back.

Is your car a beehive oil cooler or a front mount oil cooler? Because this could be a good opportunity to make the switch.

Best of luck with it!

 

I like the concept of having a second engine on hand. Like LongDuck said, doing a simple swap has far less downtime than having to tear down a dirty dead engine, finding out what you need to source, ordering it, waiting for it to arrive, then finding the time to clean, reassemble, drop it back in and so on.

These engines are very reliable (the 1st gen ones are at least), but nothing lasts forever. The peace of mind alone is worth having to store a keg in the corner for a length of time. It's not like they are super big and heavy and difficult to move around if needed. I say go for it.