This is my first post as a member of this forum / owner of an Rx-7. I purchased an 85 GS (12A) a little while ago...and although I don't plan to drive it until next summer I seem to be running into some issues already. Anyway...I need a rad...I have been looking around and have seen many a rad for sale for the 13B engine but zero for a 12A. Can a rad for the 13B be used in a 12A?

Thanks for the help

 

As far as I know they are the same. I replaced 2 in my FBs, but haven't replaced the SE rad, yet. Check it out at www.radiators.com, costs about $109, delivered in about 3 days. Also, get the correct rad cap at www.mazdatrix.com for $12 and save yourself some trouble. While you're at it, get the preformed 5/8 heater hose from m'trix that goes under the beehive, the one with twists and turns at both ends. Oil dripping from the beehive rots the damn thing and then all your coolant dumps on the road and your thermo goes off the scale within a mile and you've fried the internal water seal ORings. Replace that heater hose now and save yourself a lot of headaches. And while you're replacing hoses, get that $6 Prestone Flush Kit and put the plastic 5/8 tee into the lower heater hose on the passenger side to make draining and flushing easier.

The two most important maintenance items on your 7 are the cooling system and premixing 2-cycle in your gas. Take care of those items and the 7 will last a long long time.

B

 

Thanks a lot for all the info.

 

Oh, and another thing to insure long engine life: change engine oil twice a year or so. If you're too broke to have it done and too lazy to do it yourself then change the oil filter every couple months. You can punch a hole in the old filter on the upturned bottom and let it drain to avoid splattering oil all over. If you are too cheap to buy a punch get a case-hardened nail from the hardware store for a dime (you can tell it's case-hardened by the nice ring it makes when you drop it on the floor). Oil doesn't wear out (tho the additives do) it just gets dirty.

Put Redline MTL in the transmission: your synchros won't crash and you'll love the feel. Put Redline Differential in your diff.

B

 

I have 2 FBs, both 12a, the nice one has a rebuilt rad that is now 3 core, the winter car has a stock 13b 2nd Gen radiator, both work fine, the 2nd Gen sits lower than the original though. I just had to find a couple of hoses that could fit the relocated outlets.