Rotor housing sealing surface
 

'94 Touring currently going through a backyard/bedroom rebuild @ 80K miles.

I am going through the cleaning phase and was wondering if my rotor housing sealing surface was clean enough. Can't tell if it's carbon deposits, rust or just discoloration but the surface isn't spotless, see below.

Am I missing a product I should be using?
Do I just need to put more elbow grease into it?

Also, if you guys have an alternative to an air compressor for blowing the water out of all the channels that'd be cool. I briefly tried blow drying the water out and felt dumb so I stopped. I could pick up a cheap air comp from harbor freight but being in an apartment surrounded by other units, I am afraid I might call unwanted attention to my rather illegal engine rebuild in the car port (land lady thinks the car's on stands for a oil change HAH).

The standing water is a problem. I went over my front iron very briefly as well and overnight, I already saw a little orange in the water jacket groove. I WD-40'd but didn't apply it that liberally because it'll be at least another month before the engine comes back together. Is it a problem if I do just go soak the thing in WD-40? And maybe a quick run with a degreaser right before assembly or something.

My cleaning procedure is as follows:

1. Soak in warm soapy water
2. Rinse and spray down with mineral spirits
3. Scotch Brite green pad scouring w/ hard bristle brush and brass wire brush
4. Quick rinse under a faucet
5. Spray with Spray Nine degreaser
6. Scotch Brite again
7. Scrape with razor
8. Sand with 500 grit wet/dry sandpaper
9. Rinse
10. Spray with brake cleaner
11. WD-40 (I don't do this too much, just onto the contact surface on the inside of the housing and wipe it around with a shop towel).

I don't apply too much pressure with the sandpaper but I do go pretty hard with the Scotch Brite and the results are below:

https://cimg7.ibsrv.net/gimg/www.rx7...9f1f69c6dc.jpg

https://cimg8.ibsrv.net/gimg/www.rx7...44c4397705.jpg

https://cimg9.ibsrv.net/gimg/www.rx7...f70f0e5058.jpg

https://cimg0.ibsrv.net/gimg/www.rx7...c1d4ec4226.jpg

https://cimg1.ibsrv.net/gimg/www.rx7...44c6c687af.jpg

Thanks in advance for the input.
I didn't feel a rebuild thread was necessary for this one since it's pretty standard and I see a lot of them around anyway.

based on those pictures, your rotor housings have some wear on the surface and that's the source of the coloration. It likes the chrome surface is still there. Rule of thumb is that if you have grooves deep enough to catch a finger nail then you should consider replacing.

air compressors aren't that loud if you get the kind that are oil lubed. Your neighbors wouldn't hear it. The cheap oil less compressors can be very loud. If you are at the point in your modding career that you are rebuilding an engine you should really invest in a good quality air compressor.

Is there any significant chrome flaking anywhere? Any gouges? Cracks around the spark plugs? If not then they are a good candidate for resurfacing. I offer the service for $150/housing. I don't take nearly as much material off as I've seen some others do.

Thanks for the reply. The grooves are pretty imperceptible though I will try and get a dial gauge reading when that comes in. So the "dirty" bits won't affect my seals I assume?

I am going to harbor freight and probably picking up a cheap electric air compressor. Again, all I am going to use it for is blowing air out of passages and getting the parts dry.

While I would love to have a nice air compressor and air tools to match, living in a small ass apartment is not conducive to maintaining a garage. I don't even have a garage, it's just a car port and all the work I have to do must remain low key.
All the parts are in large plastic storage bins inside my bedroom (I have to jump over a box full of bolts, my stationary gear and oil pump to get to my bed) so things are getting pretty rough living wise.

The spark plug holes on the inside of the housing have no cracks around them. This particular housing has perceptible chattering so it will most likely not go back into the rebuild. I was just testing out cleaning procedures on it. I have another one that is smooth on the inside surface (no gouges or cracks) and of similar quality on the side sealing surfaces.

What would chrome flaking on the housing look like? And what part of the housing is resurfaced?

If its the side, would that not affect my rotor clearance?

Thanks for your time.

The flaking will be pretty obvious. I personally will not use a housing with ANY chrome flaking in my builds. Chatter will come out in most cases with resurfacing.