I just purchased my 86 RX7 a few days ago. I have to admit that i really wasn't in the market for this particular car, but after looking at the vehicle it seemed to be a very good deal to me. The car is an 86 as I mentioned with 79,000 miles on it. It appears to have been a one owner car from what i can tell. It is just a base model but it is extremely good condition in an out. In fact i wouldn't hesitate to say the interior is perfect. The exterior is great except for a couple minor dings which can be expected of a 20yr old car. Mechanically the car seems to be in very good condition. Engine runs quiet and smooth. I have read through the GenII FAQ's posted by 87 Turbo II and must say that there is alot of great info there for a first time owner. I am not at all familiar with the rotary engine. When i intially started asking around about the car it seemed that the common consensus was that it was a reliable engine that will last a long time with proper maintenance. The more i have asked around on line i have had some folks tell me that they can be big time trouble. I'm basically just looking for any input i can get from folks that are familiar with these cars. I personally havent found any issues on the car yet. What kind of things should i look for that are common problems? Any special maintenance that i should look to do on the rotary engine that would differ from a pushrod or over head cam engine?

Thanks
Kerry

 

First of all welcome Kerry.
There are many people out there who will look you in the face and tell you that rotaries are unreliable because in alot of cases they are. Matenance can keep a non-turbo rotary well into 220,000 miles or so. Most people see them as unrealiable because they improperly tune them, or improperly maintain them. First and probably most crucial is a good break in period. The first 1000 miles on the Rx-7 need to be kept under 5,500 RPM as much as possible and then 1,000 through 1,300 miles you should try to put the Engine through all of it's RPM range which lets the seals expand and shink over and over and set into place but still being used to the entire engine cycle. That is the hardest when buying an Rx-7 because you don't know if the first owner did it properly. My Rx-7 had 1 previous owne but he didn't break it in properly and I'm making low compression and seeing an engine rebuild at only 97K miles. Next is oil. The rotary engine uses an oil metering pump or OMP. The OMP injects oil into the rotor housings to lubricate the seals throughout the cycle. this oil get's burned up in the cycle and isn't recycled throughout the engine. So that means you need to add oil maybe twice a month. Just check your oil every other fill up on gas. Another things is try once every 3 months to hit redline. this clears the rotor housings and rotor faces of carbon that can build up and gum up the engine and wear away at the housings creating a compression gap lowering compression. Go to Mazda and get a compression check and that will tell you where you are with your Rx-7. Also ask to replace your pulsation dampener because it is most likely 20 years old and a PD failure can result in engine fire also it is really cheap to replace. Take thse steps to take care of the car and it will last for a very long time. The rotary only has 3 moving parts (front rotor, excentric shaft, & rear rotor) so they are pretty rock solid. Enjoy your Mazda and I hope what I have said will help out.

 

Thanks so much for the feedback. I must say so far i love the car and it drives great. Is this pulsation dampner something that a do it yourselfer can do? I just ordered a repair manual for the car so i can get a little more familiar with the operation of the rotary. what kind of money should i expect to pay for PD? Definatley don't want to risk any fires. Is it true that the oil change interval for a rotary is much longer than that of a normal pushrod engine? and what oil would you recommend. From what i was reading in the owners manual it would appear that 10w-40 is recommended from 0-80(or somewhere around there) degree temps which i just found odd for a 4cyl.

 

I run 5W-20 just because rotaries heat up pretty hot and it runs so much better with the higher viscoscity but you oil pressure rises. Just depends on where you live.. A PD is a small little rubber cap on the fuel rail. New it's clear after a few months of gas rishing through them they are yellow-ish. They are pretty cheap. I don't know how much Mazda charges for them but just stop by a delaership and ask them to replace it while they do a compression check for you (rotary needs a special compression checker anyway so you'll want to go to Mazda one way or another)

EDIT: also do NOT use synthetic oil in a rotary. when synthetic burns it leavs behind carbon which as I explained is very bad. There is a VERY expensive synthetic oil in Japan that is rotary safe and you can orde rquarts of it for here also Royal Purple works with the rotary (best bet if you must use synthetic).

 

Thanks again for the good info. I just noticed you are from atlanta. Just so happens that the shop that built the motor for my mustang is in marietta. We have been down that way a couple times with that car. Anyway, i really appreciate the info and help.

 

no problem. That's why I'm here. I know a lot about 2nd gens, sadly, like nothing about anyhting else so it's good this is the car you want to know about. Yeah Atlanta is nice if you don't mind the crime and such. What kind of Mustang do you have? My mom owns an 04 V-6 Vert. It's slright but it's only a V-6. Only thing I have against mustangs is the interior quality but they're nice and if done right really fast.

 

The main thing you want to do with a rotary engine is make sure you do not overheat it. Always make sure you have plenty of weater in it and keep a check on the oil. A rotary engine will use some oil because it is injected into the engine like a two stroke, so just keep it changed regularly.

 

We have 2 mustangs. My wife has an 06 v6 that has some minor body mods. We put the gt front and rear bumpers on it, added dual exhaust and a few other little things. If things go right we are planning on either putting a vortec ho setup or single turbo on it this winter. I have an 02 gt with a 302modular(stroked 4.6), kenne bell 2.2 twin screw, stage 2.5 heads, custom ground cams and a whole bunch of other stuff. At 17ps and 18 degree timing on pump gas it is making 625rwhp. Needless to say its a fun little car on the street. I had actually picked up this rx7 for a daily driver. However, after seeing how clean and orginal it is i don't how long i'm going to end up driving it before i want to put it in the garage and keep it how it is. I must say since i don't drive the mustang all the time with the way it is built, it has been fun having this little rx7 to go run around in. Then again, i was driving a saturn sl1 as my dd before the mazda.

 

You can use Synthetic in rotaries. I have been using Mobil 1 for years & have had no problems. That was a big thing with Mazda back in the days & have since been done away with. A lot of Rx7 owners use Synthetic oils. Also the Pulsation Dampner is metal with a plastic cover (not rubber). I think it retails for just over a $100. To replace it, the upper & lower intake manifolds have to be removed since the PD is located on the main fuel rail that sits on the engine block. I would recommend getting a FSM or Haynes manual. They will help you a lot.

 

heh sorry, I don't know where I got the idea