Heyo guys, I'm a second gen owner, and my dad and I are going tomorrow to pick up an 85 GS from mazdaverx713b. I've been a 86 GXL owner for two years, and have more or less completely rebuilt my 86. And I got dad addicted to them too As I'm sure you're all aware aware of the differences between a carb'd 12a and a Fuel Injected 13b, I'm not. So any thing you can point me in the direction of, any tips and tricks, common points of failure, etc of the 12a beast will be helpful

Thanks guys!

~Wonko The Sane

PS - Yes, I know how to search, and I'm reading through the archives now

 

Common point of failure: Cars with the beehive oil cooler tend to blow coolant hoses, see below.

Common annoyance: Cars with the beehive tend to cook the oil cooler O-rings and the dowel O-rings, causing leakage. All over the coolant hoses on that side of the engine.

Solution is to avoid '83-85 cars, similar to avoiding S5 FCs so you don't have a $1400 OMP just waiting to fail. And similarly, the '83-85 12A has lightweight rotors (almost the same weight as S5-up 13B) However, swapping to a 79-82 radiator/oil cooler setup is a straight bolt-in swap.

- Pete (Have you ever read a box of toothpicks?)

 

PeeJay - You know, it's about time to give up on society when they have instructions on toothpicks. I'd put them away for a while, and hope they get better, but I don't think they will.

Can I just get replacement O-Rings and rebuild the oil cooler o rings and such?

 

Set of orings is $13 from mazdatrix. Replace every 100,000 miles.

B

 

It's fairly easy to change the cooler O-rings, the only gotcha (besides dumping oil and coolant everywhere) is that the oil hardline from the front cover to the oil cooler DOES NOT BEND. What you do when you're taking it apart is crack the banjo bolt on the cooler loose as the first step (after draining coolant and removing the oil filter). Then when you're assembling, thread in the banjo bolt, snug down the bolts/nuts holding the cooler to the rear side housing a hair less than finger tight, THEN tighten the banjo bolt, THEN tighten the nuts/bolts.

The hardline does NOT tolerate trying to bend it.

The dowel pin O-ring leakage, of course, requires engine disassembly to repair.

 

lol i was thinking about this the other day, heres a list of stuff you will be changing on an 83-85

1. if it leaks from the dowels (i'm 4 for 3, had an 82 that leaked) you get to pull it apart and rebuild. its easy, i can do it in 14hours, some people here can prolly do it in less time

2. replace all the water hoses, and the thermostat, and the water pump and the radiator. the 83-85 1 row seems to always be clogged and the aftermarket ones are usually 2 row and better

3. tranny's usually loud, another 14hour job, dont usually end up having to do it though

4. brakes, the drum brake cars always need rear shoes, and usually wheel cylinders. have fun, drums suck! dont use mazda front brake pads, they make tons of wierd noises (the growl, squeek, grind etc)

5. shocks, these are usually tired too, but if they are worn evenly its fine

6. lube all the hinges, locks, and window channels, it makes a HUGE difference and i bet nobodys ever done it.

7. fix the vacuum leaks! its leaking from the shutter valve, maybe the intake gasket, and on my last one the air pump came apart and jammed itself in the acv, making a huge internal vacuum leak

8.put the "street port" racing beat system and a lighter flywheel, and enjoy! the cars really fun at this power level (120-125rwhp) and you loose nothing in reliability


all 3 of my 83-85 12a's were bought for under $350, and i averaged about 20,000miles on each one. total investment in each car was around $1000. cant beat that with ANYTHING ELSE!!!

DONT BEND THE HARDLINE

 

Cool, thanks for the pointers guys This Fb stuff isn't too bad, I was expecting more radical differences between it's carb'd 12a and my FI 13b, but I guess not

Thanks again!

 

12a first gen's rock. First gen's flood way less compared to fc's. Take off all the emission controls. There's a good guide u can follow.

 

hope you enjoy the car Aaron. i am glad it went to someone who will take care of it and appreciate it.

 

To be honest Dave, I don't think i'll get to drive it much My dad seems to have fallen in love with it, along with my sister, and I'll bet my mom starts trying to take it too, haha It was funny, my mom took my Rx yesterday when I came to pick up the 85, and she was telling me about how she "killed" an SUV that was being a jackass and revving and pulling out from the redlights.. . It's so funny to hear your mom talking about taking people on in your rx7

The car ran great coming home, except for the loose steering, it was a beautiful ride.

So don't worry, she's in good hands, We're going to get the steering straightned up first, then it'll be made nice and pretty thanks again!

Carlito I'm going to take off the emissions as soon as I find out exactly how much I can take off.. Stupid PA and their laws

 

i wouldnt bother, theres 4 solenoids and like 6 vacuum lines, its very simple, you gain no power and you can remove the whole thing with 2 bolts

 

just do not remove the air pump if you plan to keep the cats. an original exhaust for that car is extremely expensive and i wouldn't hack it up. i would just make one or order one from racing beat.

 

Good advice.. What we're thinking of doing is getting a "test pipe" and ONLY using it offroad *cough, cough*, but keeping the cat and airpump handy for that magical one day a year when it needs inspected

 

thats time honoured tradition right there

 

Hell, just yank the engine/exhaust/passenger side wiring as an assembly, install a betterful engine/exhaust, and a simplified wiring harness (two wires to the alternator, the driver's side harness can stay as is) and swap engines as emissions testing dictates. I'd rather just yank the engine as a complete assembly than mess around with test pipes and emissions racks and whatnot. Much easier.

This was the plan with the '80, although since it has a unified wiring harness I swapped the harness over onto the new engine. Then the '80 died and now I have this fully functional yet unported '80 engine in the garage, and an '85 (with its split up emissions and ignition/sensor harnesses) that begs for a mo' betterful engine. And emissions testing every other year until 2009. I think the outcome will be obvious.

 

Man, you and your betterful engine plans. Get that bridge or peripheral done soon!

 

Time, Jeff. Time.

 

That's what I keep telling myself. I have everything I need to get it running... I just lack the time to work on it (20B).

 

I gotta admit, if i had a 20b siting around, my time would be scarce for other projects too

I like the idea about the wiring harness, and the rat's nest is coming out rather quickly, assuming they're not looking for it for emmissions.

Thanks for the ideas!

 

Be careful when you're adjusting that steering. Really, it doesn't seem to work for a lot of people but if you follow bobrx7's directions, it's easy and it WORKS.

 

I think that was the writeup i was going to follow, where you can adjust everything without removing the rack? It seemed to have a good response.. I should be able to cut it, it can't be any harder than rebuildng my 13b or the bodywork i've done thanks for the warning, though, I'll be careful not to stray off the beaten path

 

Mainly I don't know how I'm going to admit air or fuel!

I mean, I have the general intake design laid out in my mind... but I dunno whether to use a Holley, or EFI, or twin SU's, or (crazy idea deleted but it kicks SO much ***). Plus there's the little problem of me dragging the engine to work and working on it there in the off hours, since my roommate's crap has completely taken over my home workspace.

 

What I'm saying is not to cut corners. Most people get frustrated or don't bother with things like a dial indicator or unhooking the steering from the pitman arm. The first step (setting the preload) is pivotal to a lasting adjustment.

Also, having a breaker bar and a six point socket for the big nut is recommended strongly.