Cleaning Oil Off Engine?
Seasoned HDF Member
Joined: Oct 2015
Posts: 13,537
Likes: 34,736
From: Pine Flat Dam/South Bay Area, CA
I've never had an issue using a 1-1 mix of Simple Green on any aluminum surface, including polished or natural finish. I don't use it on a hot engine or let it dry before rinsing, though.
Road Warrior
Joined: May 2012
Posts: 1,956
Likes: 75
From: CA
Found this on the simple green website:
However, caution and common sense must be used: aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green All-Purpose Cleaner can accelerate the corrosion process. Therefore, contact times for unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green product residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation.
However, caution and common sense must be used: aluminum is a soft metal that easily corrodes with unprotected exposure to water. The aqueous-base and alkalinity of Simple Green All-Purpose Cleaner can accelerate the corrosion process. Therefore, contact times for unprotected or unpainted aluminum surfaces should be kept as brief as the job will allow - never for more than 10 minutes. Large cleaning jobs should be conducted in smaller-area stages to achieve lower contact time. Rinsing after cleaning should always be extremely thorough - paying special attention to flush out cracks and crevices to remove all Simple Green product residues. Unfinished, uncoated or unpainted aluminum cleaned with Simple Green products should receive some sort of protectant after cleaning to prevent oxidation.
Cruiser
Joined: Nov 2015
Posts: 192
Likes: 20
From: MN
Dawn dish soap is my preference. I have a variety of brushes (Part cleaning, tooth, car washing..) that I'll use as well.
I've used Simple Green on V8 aluminum blocks w/o issue. As stated above, SG can accelerate the oxidation process, but I believe it to be true for any chemical or fluid that is left in place too long.
I've used Simple Green on V8 aluminum blocks w/o issue. As stated above, SG can accelerate the oxidation process, but I believe it to be true for any chemical or fluid that is left in place too long.
Seasoned HDF Member
Joined: Oct 2010
Posts: 12,230
Likes: 7,806
From: Along the shoreline in SW FL
I use carb cleaner spray or engine degreaser foam first.....blast it off with the hose good. Let dry. Can leave it that way, or if you want that nice showroom "wet look" on the engine, I coat it after with "Pig Spit" (similar to S100 but I find it lasts longer).
Seasoned HDF Member
Joined: Jun 2010
Posts: 9,332
Likes: 3,873
From: Upstate New York
I dilute the S100 1:1 with water, and always wet the motorcycle before applying. Also don't let it dry on the motorcycle and rinse thoroughly with plenty of water.
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