Eric11

hey my name is Eric, i just bought a 1983 mazda RX-7 without an engine for next to nothing. everything is in just immaculate condition other then....well....no engine anyway ive seen a couple adds for engines on sale but im very new to these engines that i dont know what to look for when picking one up. i guess my question is, what should i be looking for when picking up a rotary engine? i was just at a guys house who owns 3 (2 of which are the 13b's and 1 12a) and i didnt know what to look for. they turned over which was good but what else would be something to look for in while looking at these engines?

phinsup

Welcome aboard Eric, I am going to move this to a more appropriate section so you can get some more answers.

j9fd3s

hi there!



there are a few things you want to look for in a used motor.



1. is it the right year and model? the 83-85 12A engines are the same, and would be a bolt in. 13B is a very easy swap.



2. the 83-85 12A engine is pretty easy to spot. on top of the aluminum rotor housings, it says 12A and mazda. on the rear iron housing, there is a heater hose connection, on the 83-85 motors it is a T for the weird oil cooler that is mounted on the rear iron. 84-85 engines have the engine wiring harness that goes to the US passenger side, instead of the 79-83 which goes the other way.



3. condition: hows it look? from the factory the engines are not painted, so the rotor housings are bare aluminum, and the irons are iron colored (they are actually coated with a nitride that is grey...). oil pan was black. if the engine is painted, its likely been rebuilt. also look for stamps, the mazda rebuilds had a stamp on the front rotor housing around the 12A area, usually its a date and initials, or after 96-97 they put a blue tag on the front cover.



you want to pull a couple of spark plugs and make sure it has compression, no compression = no run.

dfwrotary

I say go with the 13b engine, the newer the better....

Eric11

hey thanks all for the advice! im gonna go pick up the 87 13B.