Best way to remove carbon from rotors?
 

Prefcae- nothing happened to my motor, just getting a “spare “ready

So just picked up a low mileage FD motor, and am starting to get all the bits ready for machining. The rotos have a decent ammount of carbon, nothing horrible but I was wondering if theres a easy way to get it all off chemically? I’ve used berrymans chem. Dip years ago on small engines and was blown away, but hear now it’s nothing like it use to be. And if I can avoid 2hrs of scrubbing and spraying with carb cleaner that would be awesome
thanks

I followed Rob's video (pineapple racing), only took about 15 mins for all 6 faces.

Cleaning Rotors

Side/apex/corner grooves are a whole different story tho.

Yeah, I gently wire wheel them and then a bath is Purple Power. The Purple Power does a great job of eating carbon but it will eat the bearings and anything aluminum as well. So you don't want to let the rotors soak in it if you're reusing the bearings.

scrape the faces with a razor blade after soaking them in degreaser, use a steel wire wheel on a drill to clean the compression pockets. then wire brush them with a brass brush on all faces(except bearing face), go through the side seal slots with an old side seal, go over the corner seal slots with a dremel and a small wire brush that fits in the slot, go over the oil seal carbon channel with an old apex seal, go over the apex seal slots with an old apex seal, let them soak in degreaser for a few hours then finish with a pass from a brass wire wheel on the drill.

main points, try not to brush the corner seal slots too thoroughly, you can widen it and make the corner seals sloppy. if reusing the rotor bearings don't scrub the insides of the rotors but let the degreaser clean those spots out. try not to scrub the plating off the rotors, the brass from finall cleaning should leave an anti corrosion film on the rotors which will actually bake in once the engine is run.

purple power isn't too harsh on aluminum and bearings if you dilute it 70-80%, if you use full strength and soak it overnight then you will see a huge difference in how much it will etch the aluminum. rotor housings will come out a dark grey versus a shiney silver.

I used a brass Dremel bit on the corner holes once after using the technique before and I warped the holes using to high of a speed I suppose. The corner seals would not slide smoothly after. Just go slow on them.

gotta go a little slow, shouldn't take much to clean those corner seal holes. much easier than scraping them by hand though. brass is more of a finishing material than a cleaning material also, i only go over things with a brass brush once all the carbon is off, because the brass will just pile up over the carbon and thicken the surface versus clean it.

Be careful when using old apex seals and side seals! They can be very sharp! I found out the hard way.....

Varsol bath, wire wheels and wire brush have always worked well for me, plus using old seals to clean the seal slots out.

Same here, specially when using parts from the older 3 piece apex seals. OUCH!

I let m

I let mine sit in Diesel for two days and green pad with brake cleaner. Works for me or ATF its very high in detergent + green pad and brake cleaner.

Send them to the local machine shop and pay them to clean all my rotors haha.

They charge me $120 to acid bath all the irons and rotors. Rotors come back minty clean, all the apex seal and side seal grooves are perfect. Ready to drop new seals into.

Not worth my time to do it myself.