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I don't remember where I read it, but I use Krud kutter in the red bottle and it's been working great for several years now for everything from carbs to firearm parts to tools and auto stuff.If it's aluminum, I don't leave it in for very long, maybe 30 minutes tops. I also only add an ounce or two to hot water to fill the tank.https://www.lowes.com/pd/Krud-Kutter-32-fl-oz-All-Purpose-Cleaner/50296427
Dawn works great. Avoid acidic solutions; brass comes out nice and bright, but quickly corrodes.