Cleaning Aluminum Valve Covers

For cleaning delicate parts like aluminum carburetors I have used original Pine-Sol. I know it sound weird but the product with the pine oil verses some other products. Some people have made larger "sonic" cleaners by attaching a palm sander to the container while the parts soak. I last time used a 25% mix Pine-Sol with water and had very good results. It's gentle enough to not destroy the rubber parts but cleaned all gunk off. Having them blasted is also a great way to go. If you have Leanna clean them you may ask about a protective coating to keep then looking good.