I'm finally getting around to tearing apart the perfectly running 12A from my '85 due to hemorrhaging dowel o-rings (prolific amounts of oil loss!). That leak is the only issue with the engine - it starts right up hot, cold, after sitting all winter, etc. Runs strong, doesn't smoke, blah blah blah. Like I said, it's a perfect 12A except for losing enough oil down the side of the engine to make the exxon-valdez jealous.

I have the gasket set (N201-89-100B) from Atkin's and will be ordering the front and rear main seals (didn't realize they weren't included, oops). The engine is on the stand as of today, will get into it this week. I'll check and measure stuff, but don't anticipate finding anything particularly wrong inside.

Here's my question: Do I need to order a new set of oil control ring o-rings (ala Atkins' ARE15) as a matter of principle because it has been taken apart, or are they something that when I have it apart I may be able to inspect and determine if they are still good? Not looking to spend a ton of money on this, but willing to do it right. Seems odd that these aren't included in the kit which is otherwise all the 'soft' seal parts for the engine, thus I figured I'd ask.

Thanks!

 

Honestly, if the engine is going to be torn down, I don't see why not. I would replace all consumable parts. If its done right it can last many many more years without having to worry about consumable part failure. Fingers crossed that the housings are still good and that you don't find a lot of chrome flaking.

 

+1 change the oil control rings. Atkins sells their own O rings, and they work ok, but the fit is not very good.

 

Are the Viton ones from Atkins the ones you're talking about (https://www.atkinsrotary.com/store/6...s-ARE15.html)? I feel like I've seen mixed opinions on them, but with the mazda ones at $160 a set I can see their appeal at $40.

My other concern would be with the oil ring springs - I doubt at this point they would still have their blue/white paint on them. Is there another way to tell them apart, or once the oil rings come out do they need replaced, as they'll be indistinguishable?

(Probably dumb questions, but while I've done plenty of piston engines, this is the first rotary work I've undertaken)

 

they are directional, if the paint is gone (probably would be) you just need to figure out which way they go back.

OR

B, you have 4 trays, one for each side of each rotor. the rotors are labeled. best practice is to take it apart in a way that you could put everything back where it came from.

 

Seems reasonable. I suspect like most things once I see it, it'll make sense. I assume there's a large and small one per-side, and there is a hooked end from what I can tell which goes into a retaining feature on the rotor/ring. I do plan on painstakingly laying everything out to go back together in the exact orientation it came apart in, so I suppose that will alleviate the ring spring confusion - thanks! I'll plan on ordering a set of atkins' viton o-rings when I order the main seals and anything else I discover I need during tear-down/inspection.

(Ring Spring Confusion would be a good band name)