Images:
What I started with.
What I think is clean.

I did not get all the carbon out of the rough combustion areas.
There are a few very small "nicks" on the outer curved surfaces.
No major signs of damage (like what I see in the videos).

It looks good to me holding it.
But, this is the first time working on a rotary. (Last engine I rebuilt was in 1972. A VW flat-4, air cooled, from my '60 Karmmen Ghia.)

 

IMO, since the rotors will be dirty about 10minutes after the thing starts, really the bearing/seal grooves are the important part.

i'd be happy with those (provided the grooves are clean)

 

Yes the bearings and all seal grooves are clean.
Just looking for a target level.

Thank you.

One down, one to go.

 

What I do is I take a nylon brush and scrub them with GUNK Engine Brite... engine cleaner in the aerosol can. Then I take a fresh flat razor and gently scrape the sponge carbon off of the flat surfaces around the compression dimples, and flat surfaces on the front and rear (with GUNK). Be careful not to scrape any of the seal grooves heavily. Dont warp them is what I mean. I always take an old side seal, apex seal, and corner seal to scrape the inside of each respective groove clean. This also clearances them.

After they are cleaned I draw a bath of Purple Power or Simple Green in a big Rubbermade storage bin and dunk the rotors several times to flush out debris and rinse.

Finally lightly coat them in WD-40 to prevent rust.

 

NCross,

I heard of the razor on the sponge carbon, but being over cautious I soaked the rotor in Simple Green and scotchbrighted off the goo.
The hardest areas so far were the grooves for the inner and outer oil-seal rings.

Did the dip and dunk & rinse, but thanks for the WD-40 at the end. Excellent.

 

you occasionally see people go and polish the rotor faces, until they are shiny, which looks great. however if you've done this, and then pull the engine apart the rotors will still have a coating of carbon on them after like 2,000 miles.

 

I used a tiny flat head to get the oil ring grooves. Works on coolant seal grooves too. Just dont apply pressure. Lst the weight of the screw driver do the work.

 

Yes I cleaned till I could see metal clearly. Overdone, but I also wanted to see if there was any damage to the surfaces. All I could find was a few 1/16" long, very narrow, not deep indentations.

 

Yes, small flat heads (jeweler's) then wrapped in a towel to wipe out the residue.