Ok carb experts, I need some help. I've rebuilt quite a few carbs over the years, and had great success with the old carb cleaner that is now extinct. The newer stuff just doesn't work as good in my experience. I do have some original nasty stuff I still use but it's losing its effectiveness. So after alot of youtubing and net searching I decided to try a 50/50 pine sol/ water solution in my homemade ultrasonic cleaner. It does do a pretty good job but it also takes off the goldish anodizing on the carbs. (Rochester 2 jet and Holley 4bbl). My question for carb gurus..... could I possibly get a somewhat satisfactory look by just doing a sodium dichromate dip after washing off the pine sol soak or a bead blast, or do I have to do an electroplated zinc coating first? There is a great YouTube video of that process but he said he is into his system for about 1000 bucks. Too much for me homebuilding.
I have used a brush on product from a bottle to gold anodize a carburettor, with mixed results. I have used the same product on aluminum, and it worked quite well. The product I am referring to, is not available anymore, but I did a search, and the company in the link below sells kits. Might be worth a try. For doing zinc: https://www.caswellplating.com/electroplating-anodizing/zinc-plating-kits.html The link below is for aluminum. https://www.caswellplating.com/anodizing-products/anodizing-dyes.html Bob
The greenish-gold (or goldish-green, your choice) color on zinc alloy castings is NOT from zinc electroplating! The castings were dipped in a "cold dip" (no electrical current) of nitric, sulphuric, and chromic acids. The "color" is a chemical residue of the chemical surface etching of the metal. DO NOT ATTEMPT TO DUPLICATE THIS PROCESS AT HOME! Chromic acid is on the EPA's NoNo list for good reason. According to the literature available, it is a known carcinogen, and also causes dementia. Best to leave this to professionals that have the safety equipment to handle it properly. There are some other chemicals which approximate the color. Have seen many different posts on various forums over the years, but didn't try them and didn't write them down. Have never seen any that really give the correct color. And I have found, that the use of an ultrasonic cleaner using Dawn dishwater soap, does an excellent job on grease and dirt (not carbon), and does NOT remove the original color (if still present). Be safe! Jon.
For any recoating you want to avoid blasting the surface. Unless it's paint of course, but for most zinc-ish replate services it will come out looking like cheap rattle can when done over a blasted surface. We've all seen the "restored" 60s car with the zinc/gold replated hinges that look like paint, right? For that color/effect to look right it has to be over smooth or virgin metal. Strip in molasses or the like, don't go for an etch or sanding or blasting. As an aside, I've never tried it on a carb and the advice above about the acid treatment that gives the carb look, what about something similar to gun bluing fluid? When I do a Packard 12 the gauge cluster facia is finished with a silver oxide relief area (it's fuggin beautiful!) and I did that my using dilluted gun bluing then finished the rest as needed after. It's a lovely charcoal grey once done with brushed silver borders. So to that end I wonder what it would bring out in a carb body and might be worth a try.