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R75/6 cleaning engine aluminum

ripperfarms

New member
I have recently purchased a 1976 R75/6.

The aluminum engine sides and parts need cleaning. They are oxidized.

What is good to use on these parts.

I bought a Mothers cleaning ball today for my drill but it just turned the engine sides dark gray.

I also bought Mothers Aluminum and Mag Cleaner but I did not have much in the ball.

Now that I turned it dark gray I wish I would have left it alone. It looked better with some oxidation on it.

I don't want it "brightly polished" because I don't want to have to keep it that way...just ride.

Any ideas appreciated.

Dave in Central IL.
 
Hit it with some wd 40 and a plastic bristle brush. This should remove the grey eventually. There was a vendor at ama vintage days selling a product called a liquid metal cleaner called Strong Arm that seemed to work pretty well. I bought a can but haven't tried it yet.
 
Hit it with some wd 40 and a plastic bristle brush. This should remove the grey eventually. There was a vendor at ama vintage days selling a product called a liquid metal cleaner called Strong Arm that seemed to work pretty well. I bought a can but haven't tried it yet.

I used WD40 and a green Scotchbrite pad on mine. It looks pretty good.

It takes a while, but the elbow grease will be worth it.
 
Diesel and a parts cleaning brush...but your shop and clothes ...and body...will smell like diesel for six months.
:usa
 
age old hassle

Sorry – No easy way that I've found to clean the oxidised castings.
Elbow Grease will be a component of any proceedure short of disassembly and media blasting
(and my vote is for soda if that option is pursued)

What works well for me is spray Carb cleaner, scotchbrite pads – and lots of the above E.G.
Followed by a light wiping of Fluid Film, a corrosion preventive/protectant spray to 'seal' the surface.
Fluid Film is a product like WD40 – but less corrosive.

Mother's is a decent polish, and if the color left is 'dark grey' – I'm guessing the polish and residue has not been (completely) removed.
Mother's works best when working a very small area at one time, followed quickly,
before the stuff dries, by a good buffing with a clean cloth to remove all polish and 'grey matter'.
IF the 'grey stuff' dries before it can be removed ... CARB CLEANER works well to loosen it up and get it off.
Note: in any event, Mother's works best on polished aluminum surfaces.

Many will use an acid based aluminum (mag wheel) cleaner, which can work, but follow directions implicitly – or the results can be disastrous.
 
I searched the archives and tried (I think) every method of cleaning my old corroded cases and covers. They still had a blackened, splotchy look. After all this scrubbing and scouring, the engine was REALLY clean, however. As it was out of the frame, I sprayed it with etching primer and cast aluminum engine paint. The color on the engine block matched my newly blasted cylinders and heads perfectly. 6 months on, and it still looks great. The purists and scolds will blanch and howl, but it worked for me. YMMV
 
Keep it nice after cleaning

My mechanic uses Krylon clear plastic ignition spray after cleaning the corrosion off aluminum parts. It gives a satin-like finish and prevents re-occurance of the corrosion.
 
Hello "his son" I used on mine mothers powerball mini and powermetal polish worked like a champ no elbow grease required.
 
I used WD40 and a green Scotchbrite pad on mine. It looks pretty good.

It takes a while, but the elbow grease will be worth it.



+1

Other things that work.

Kerosene and scotchbrite pads.

My wifes, mini steam cleaner and a toothbrush.:bolt

If it seems simple, and quick, it won't give you the results you want.:deal
 
ignition spray

My mechanic uses Krylon clear plastic ignition spray after cleaning the corrosion off aluminum parts. It gives a satin-like finish and prevents re-occurance of the corrosion.

Krylon ignition spray ? ... silicone ?
 
I searched the archives and tried (I think) every method of cleaning my old corroded cases and covers. They still had a blackened, splotchy look. After all this scrubbing and scouring, the engine was REALLY clean, however. As it was out of the frame, I sprayed it with etching primer and cast aluminum engine paint. The color on the engine block matched my newly blasted cylinders and heads perfectly. 6 months on, and it still looks great. The purists and scolds will blanch and howl, but it worked for me. YMMV

Got any pics? :dunno
 
Kind of hard to capture the texture, but this shot should give an idea.

paint.jpg
 
What I use...

I use stuff called "Oil Eater", its simply a concentrated detergent that will not get into your gaskets like some of the above can. Plastic bristle brush and low pressure hose. This stuff is good at cleaning grease and oil spots in the drive way.

Your car parts store should have it...try it. :)
 
unless its looks really awful, powerwash it, dont get to mental about it and worry about changing the oil often. ride it. does it run like a solid beemer? you might end up screwing up the finish. remember what we say in surgery...."better is the evil of good".
 
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