Maintenance and known problems

Mylacc · 12-01-2001, 07:54 PM

ok im thinking of buying one of these but people keep adivisng that there high maintenance and even then that they have alot of problems and reliability issues

which is a shame because is it just me or does the rotor engine do something else for this car. give it a glide like feel

i swear to god this car feels like your floating when your driving it. its freaky its zany and i love it

but it wont feel very glidelike if its always f**ked up and parked on the side of the road.

JD@af · 12-05-2001, 12:00 PM

My buddy Henry's brother has a beautiful second-gen. RX-7, awfully fast (I think he can run consistent 10.6-sec passes), and in the past year or so, he has cracked the left oil channel on the rear head FIVE TIMES (i.e. on five different heads - all in the exact same location). I need to find a web board to find out how other RX-7 owners are dealing with this structural weakness (he hits this problem in the vicinity of 30 psi of boost - apparently this channel contains a hollow steel rod which gets blown laterally with enough force to crack the oil channel in which the rods resides). Below this boost level, he has had no major concerns. But then again this car is basically a garage-kept, occasionally-used drag racing car.

EfiniRX7 · 12-10-2001, 11:04 PM

Depends on what generation you're looking at. The 1st and 2nd gen cars (even turbo models) are definately reliable. I know quite a few guys with nearly 200k on their original engines. Now 3rd gens are a different matter altogether. They are inherently not reliable for a number of reasons. Rotary engines create a lot of heat compared to a piston engine and Mazduh put a catalytic converter immediately off of the exhaust/turbo manifold. This created a lot of underhood heat which is definately the enemy of any engine..especially rotaries. Anyway though, if you really want some good info on the cars check out www.rx7club.com and go to the forum section and also look at www.scuderiaciriani.com TONS of good info there too plus a "Buyer's Guide"

PS I highly doubt that guy was running 30psi in his engine...unless it was a totally worked and ported race motor. I can see guys like Abel Ibarra running that much boost in a low 7sec car, but not in a 10sec car. The rear rotor housing tends to be the unlucky one due to the extra heat in the back of the engine bay so that's likley why his rear housing/rotor keeps going out on him.

JD@af · 12-11-2001, 09:15 AM

Awesome. Thanks for the info. I’ll pass this info on

SuperchargedRex · 12-12-2001, 10:12 AM

The rear rotor usually dies first because Mazda programmed the fuel cut to the rear rotor when you hit the rev limiter. This causes the rear rotor to run lean, which leads to detonation, which leads to blown apex seals, which leads to "time for a rebuild."

As for the original question: I got 168,000 miles on my original motor before my oil seals on the sides of the rotors let go. The NA motors tend to be more reliable because theres not much you can do to screw them up. Its my belief that the turbo motors have an undeserved bad reputation due to owners making bad modifications: they up the boost without supplying sufficient fuel, and you end up with a lean condition. (See the 1st paragraph.)

JD@af · 12-12-2001, 10:19 AM

For the lean-programming condition, sounds like the system could benefit from an ECU with the rev limiter removed, and a spark cut-off initiated, like that found on the MSD 6AL agnition. Man, this is really awesome info. You are really going to help make a difference in how my friend’s car is able to run. I’ll check into www.rx7club.com and www.scuderiaciriani.com to see if they have any more tips, or suppliers for better engine components (or even a first of second gen. engine!).

SuperchargedRex · 12-12-2001, 10:27 AM

Most of the guys that upgrade their turbo motors, add a Haltech computer to control the air/fuel ratio and eliminate the fuel cut.

EfiniRX7 · 12-12-2001, 01:18 PM

I definately agree about the 1st and 2nd gens being relatively reliable. I know quite a few guys with nearly 200k miles or more on their original motors, but then again n/a motors tend to last quite a bit longer. The 3rd gens have an unncessarily complicated turbo control system, a relatively small radiator, and a useless intercooler all of which add up to inadequate cooling and overally complexity. AFAIK the fuel cut on the FD's is to both rotors, but I'm not positive. An upgraded ecu like the Haltech, A'PEXi Power FD, and Wolf 3D are good, but expensive upgrades usually running $1200 and up...plus the Haltech needs a laptop to be able to tune it. Heat is a huge factor in killing rotaries as they naturally burn really hot compared to piston engines. The rear of the engine bay gets very little cool air...at least not enough. The coolant and oil passages in the engine aren't all that big either. A lot of good rebuilders will port the coolant and oil ports when rebuilding an engine thus allowing for a cooler temps. Scoot makes a hood now that has an air duct running directly to the rear of the engine compartment so I'm sure that'll help too.

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