Rebuild tasks today - managed to get the new JE piston and cylinder and into Ron's shop @ RB Designs! Looking at a pick up Monday.
I had some time this afternoon to try out the 7% Nitric Acid we mixed up in our lab earlier this week. I've been trying to read anything on the web about cleaning aluminum with nitric acid this week, and it looks like a very effective "desmuter" in the anodization process for alumium. Once aluminum is cleaned in alkaline caustic, the nitric acid "desmuts" the aluminum and leaves it clean for anodizing.
I used steel brushes to scrub and sprayed on the 7% Nitric Acid on concentrated small sections to scrub or 10-15 seconds and then rinse. At this concentration the de-staining worked, but took quite a bit of elbow grease to remove the baked on dirt on the motor. I think I may try a slightly higher concentration of Nitric Acid on the next time I have to work on the motor cleaning.
Another dry, warm day in Oregon in January
This acid washing business is definitely for the outdoors with proper precautions. Good gloves and eye protection are key.
Valve cover is cleaning up nicely
Compare after acid washing to the stained case
Still a ways to go on the cylinder head, but slowly getting it cleaned up