Looks like the long life of the 12A in most recent Rx7( 5th to be exact) could be coming to an end, soon, at 227,000 miles without a rebuild. This Rx7 has become more and more difficult to start lately. When it does start it never smokes and when I drive it still has plenty of power, but it still has low compression according to a recent compression test at the local mazda shop. The cold weather isn't helping with start up either.

For know I might replace the starter because sometimes even with a jump start, the motor won't turn over and start up. However I think I will just go ahead and purchase a new engine, instead of waiting until next spring. I have about a $3500 limit to spend. I'm glad I didn't spend any of that money on better wheels and tires.

Any ideas on where I could buy a good engine with that amount? To bad there's a waiting list for JDM 12ATs right now from rotaryshack or I would just buy one of those engines for $1200. Any feedback would be appreciated. Thanks

 

you can try ebay. With that much money you could probly get an FD swap done. You could also concider doing a rebuild with a bridgeport. If you have enough money left over, you can upgrade carburator too.

Thats just my 2 cents

Ted

 

Try a new starter first. You can prolly get one for $15 at the local JY, and it only takes about an hour to do.

 

Try a new starter first. You can prolly get one for $15 at the local JY, and it only takes about an hour to do.

 

Giver her a tuneup and check your timing before anything else. If you timing is off even a little bit it can make it very difficult to start...

 

Slow cranking also will show up as low compression... There's a reason they specify 250 RPM or more.

Starter and battery cables are a winter must have... I use em as stocking stuffers.

 

Check your battery and the battery cables. Could be bad ground connections or decaying cables and/or a weak battery are your only problems. These are lot cheaper than an engine.

 

Carbon buildup will also **** off comp numbers if its getting into the seals, and make for harder cranking... seafoam her and "drive it like you stole it"

 

For $3,500, and a waiting list on 12at's from Rotaryshack, why not just order the TII for the same price, or buy the TII from the 87-89's and get the tranny with it. It would give you more than enough money left over to install it (if you can install it yourself), and upgrade the fuel system etc. etc.

 

i have a complete restore JDM 12at from rotary shack...with a few extras but definitly worth the wait...!!

 

I checked over the car today. The negative battery cable is frayed, so I will replace it along with the other battery cable and terminals. I still plan on replacing the starter as soon as I can get one. I will also use some MMO to clear out any carbon build up that might be in the engine.

As far as a replacement engine goes, I'm considering several different options. Including either a 12AT, a GSL-SE 6 port 13B or a TII engine. However do to my lack of electrical experience I will probably just go with a ported and polished 12A with new rotor housings and race apex seals, plus a warranty. The 12A would require the least work and would be easily upgradeable for the future and still pass emissions. Thanks for all the feedback.

 

I have a ? have you ever MMO'D your engine before? If not I would not suggest this at all. You see your engine has created a seal. Carbon and deposits and filth you caould say. This seal is also on your oil control rings. If you MMO your engine the active detergents in MMO will soften these sealers and your car will begin to smoke It happened to me. MY 85 SE 190k never smoked well cared for tried MMO a week goes buy still smokin now it always smokes on start up this is not a fluke thing either. There are others that can contest to this especially with the amount of miles you have on your engine I would not reccomend this my 0.2 cents. Replace what is bad and give her a tune up. BTW what were your results from Mazda?

 

I can't remember the exact results of the compression test from Mazda. I was told that the engine had low compression, but it still had a lot of life left in it. At the time it had the wrong spark plugs in it from the previous owner and the oil pressure guage never read above 70. So not to soon after the test the Rx7 had a tune up done. There have been several repairs done since then. When I drive the car it still feels like its has a lot of power (though not anything close to the power that my 83' Rx7 bridgeport I had) and it never smokes, even after sitting for months at a time. Now the only problem it has is starting up in the cold.

 

Here are some pics of my 1983 bridgeported Rx7. It was my second Rx7, out of five Rx7s, and I had it from 1995 - 1998.

 

RXcalibur - where did you shift at with the bridgey? how wide was the powerband, and how much did the idle suck?

 

Been a while since I drove that car so bear with me as I provide some numbers for you. The idle was set between 1800 - 2000 RPM. Powerband in the low gears was from 3000-7000+ RPM, High gears 4000 - 8000+RPM. A lot room to play with. For the most part I drove it regular and reserved the hard driving for when challenged. When racing I rarely had to shift into forth gear.

1rst - 2nd 20 mph
2nd - 3rd 60 mph
3rd - 4th 105+ mph
4th - 5th 130 -135+ mph EST
5th - never reached top speed probably 150 mph + easy

That 83' Rx7 bridgeport was a mean car and could catch every gear. Though it appeared to be a simple car, all of the local Mustangs, Camaros, and pretty much anything esle (including other Rx7s) learned their lessons fast. I paid $2000 for the car complete. The engine alone , at the time, was worth over $5K. However it was very unreliable, not a daily driver, liked to spit flames, sounded like a chainsaw, and eventually blew a synchro. So I traded it back to the previous owner for a 1989 Rx7 GXL.