Sobran

Let me preface this by briefly explaining that I am not exactly a car guy. I have made it a point to learn as much as I can about cars in general and the RX-7 in particular. So my knowledge may be on the short side but I possess a keen sense of logic. Take it easy on me.



Recently I managed to kill my engine by running it too low on oil. I was low on money and hadn't realized how low my oil had gotten. In any case, before this event the engine was burning oil faster than the manual states is the norm. I was going through about a quart a week. I understand this simply happens as a rotary ages.



After I killed the engine (ironically, on my way to buy oil), it began to burn oil much faster. I go through about a quart a day on a bad day. It expels a lot of blue smoke, particularly at lower speeds. It seems to emit more blue smoke at higher RPMs, at least in the first two gears. If I accelerate slowly, it seems to limit it, but I'm not sure on this point. Also, I may not notice it at higher speeds/gears as I'm leaving it behind too quickly to see.



The car still runs pretty good, aside from the problems that it was already having.



So, my first thought was the Apec seals, as I heard they go out frequently. But I'm a little unclear on how that much oil could get into the engine to be burned in the first place, which made me think the oil metering pump may be the culprit. I've also read something about oil control seals, but I'm unclear where those are and how they might affect things.



Anyone care to guess my most likely culprit and a suggested course of action?



Edit: It's a 1982 RX-7, with a 1984 13B shoved into it.

zeroecco

This is an easy one, although it does suck what happened to your motor. The oil control rings and side seals gave out to wear. the oil control ring is on the ex centric shaft keeping the oil in the rotors, the side seals are on the rotors themselves and are also keeping oil outside the combustion chamber.

Sobran

So from the sounds of it, I'm going to have to open it up and replace all the seals. Is this even viable at this point, or is my engine two hops and a skip from being DOA anyway? I guess what I'm asking is: should I bother repairing it?

yetterben

as long as all your doing is burning oil there is a pretty good chance that the internals are still good. Stop driving it!!!!!! if you havent chucked an apex yet and you would know if you did car would run on one rotor and look like its gonna jump out of the hood you should be good. Know that being said the rotor houseings might be chipped or flakeing inside but that just comes with age. Only way is to pull it and yank it apart!!!

j9fd3s

if you ran it out of oil, chances are the iron housings are damaged, when the oil gets hot it blues the housing, and toasts the rotor oil seals, then its gonna burn oil.... keep in mind this has nothing to do with the compression so it'll run fine



no real way to know how it is without tering it down, possible it just broke an oil seal o ring, in which case everything else is prolly nice

Chris Taylor

Actually if you completely ran it out of oil, whats most likely to happen (or has happened) is you've destroyed the bearings. If it's still running, chances are this hasn't happened. Yet. You'll notice pretty brass colored flakes when you drain the oil if the bearings have started to wear, and eventually one of these flakes will clog up the oil passages and you'll have 0 good bearings left in the engine.



The irons can be lapped/resurfaced for ~$50 per face, and should be done when you rebuild anyway (assuming you rebuild for longevity).



If the outside of the engine and your engine bay are oily, then chances are the o-rings around the dowel pins are leaking as well. They're located high on the drivers' side of the engine (usually the forward most o-rings start to leak first, close to the distributor) and low on the passenger side.



When you take the motor apart to rebuild, budget around $800 for all the seals and gaskets in the engine. You can get a few here and there for cheaper from various sources, but if you call Mazda and order a rebuild kit, that's what it'll run you. Any machine work you need to do (resurfacing, balancing, new bearings) will add to that.