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What Brightens Aluminum Engines?

P

pstanisa

New member
I recently acquired a '74 R90/6 that I am in the process of getting going again. The aluminum parts have all darkened with age. Is there is any kind of treatments, sprays, or washes that can brighten it up again?

I thought about trying some of those wheel cleaners but didn't know how they would turn out.
 
engine brightners

Everyone has a favorite snake oil product. I found that WD 40 and Scotchbrite pad works. For really heavy corrosion (as we get here in the salt air of costal Florida), I have used Soda Blasting. Get a cheap siphon blaster at Harbor Freight, Soda at Graingers, and have at it. Give it a water wash afterward, dry and hit with WD 40. It will look like new. Best part of this is that it requires no scrubbing and rubbing.

Tom Barnhart
Port St Lucie, FL
Recently cleaned 1980 R65
 
bright aluminum

YUP, same stuff. Available in 2 different grits at Graingers. About $45+- for a 50 pound bag. Better than any other media since it washes off an leaves no grit. Only down side is that it kills grass..big time..damhik
 
bright aluminum

Soda is more gentle than beads or walnuts. Less abrasion to the metal, I am pleased with the results. If you boost your pressure you can duplicate sand, walnut shell or bead results. The great part is that there is no grit to get into moving parts. Just hose it down and coat with WD40.
 
TomBarnhart said:
Soda is more gentle than beads or walnuts. Less abrasion to the metal, I am pleased with the results. If you boost your pressure you can duplicate sand, walnut shell or bead results. The great part is that there is no grit to get into moving parts. Just hose it down and coat with WD40.
Click to expand...


It's also a much smaller particle so it leaves finer finnish. Here's a before and after photo of a carb cleaned with soda blasing.

Well, I thought I had 'em. I'll post 'em tonight or tomorrow. It's nice.

btw, don't go too hog wild with any type of "elbow grease" solution. A BMW engine is rough aluminum for a reason. That finish has more surface area, due to the peaks and valleys, than a smooth polished surface does. The shinier the engine block, the less it cools itself.
 
Keep up posted on your progress. I'll be doing the same thing to my Dad's 74' R90/6 I am restoring.
 
Alu cleaner

I thought about trying some of those wheel cleaners but didn't know how they would turn out.[/QUOTE]

Be wary of some of those wheel cleaning chemicals, and do not use them of any polished surface - they can be aggresive. I have done some damage, and they can be very corrosive to other metals.
 
pstanisa said:
So, soda blasting an assembled, running bike has no downside? (Other than dead grass)
Click to expand...


I didn't say that. I said it was the best alternative. Several things to be very careful of: Don't "blast" straight at any seals, make sure you have the intake and carbs well protected from the blast, listen to your instincts, if it worries you, don't do it.

One last thing, I'd change the oil after running it for 10-15 minutes. Sure, soda isn't sand or peach pits, but it's not oil, either.
 
Aluminum polishing

The is an aluminum billet cleaner by "Mothers' on the market. They make 2 grades, I've only used the less expensive one. If the aluminum was polished before and on oxidized now, it will bring the aluminum to a very polished look. It is a wipe on-wipe off product.

If the aluminum is rough, jewelers rogue and a buffing wheel will do the trick. (Alot more work)

Ralph Sims
 
Ok, called the local BMW dealer, who put me in contact with a motorcycle detailer. Her suggestion --> Lane's Aluminum Cleaner. Amazon sells it, so it might worth a $15 dollar investment. Supposed to be a spray on, wash off cleaner. I'll let you know how it works.

I'm ready to start the bike this weekend. I rebuilt the front brake, changed all the fluids, replaced the fork gaiters, and flushed and resealed the tank (it was stored with gas in it), and put in a new battery. I put a new set of points and condenser too.

The carbs are soaking right now in what passes for carb cleaner these days. A rebuild kit, and new needle jets and jet needles should get them in good shape.

Been cleaning furiously, and it's starting to look like something.
 
I've used SOS pads with a light elbow then cleaned/buffed hard then lightly with Autosol. Turned out not too bad. As for the baking soda, my dentist uses it on my teeth as a pressurized blast. I figure if it's fine for teeth and gums, it must be ok for aluminium. Just gave me a thought; has anyone ever used Arm & Hammer tooth paste to polish metal? It's claim to fame for cleaning teeth is baking soda.
 
I just read my last post and it sounded prety hoaky. But just remember some great cleaners have been found in the strangest places. Try cleaning gold, silver or brass with a bit of spit and cigarette ashes. Quite amazing!
 
The Disclaimer: I never tried this on a BMW case, but I used it with good results on Alfa Romeo cast aluminum cam covers.

There is a product made for treating bare metal (steel) prior to painting called Metal Prep (it's a brand name that has become somewhat generic). It is acid based. Available at automotive paint stores. Wipe it on with a rag or "paint" it on with a brush, let sit for a few minutes then wash it off with water. Easy.

The Alfa parts were not polished, as the BMW cases are not polished. The stuff cleaned and brightened the aluminum significantly - like it came from the factory - without the trouble of scrubbing, blasting or polishing. I'd not hesitate trying it on an Airhead case (if I had one).

John
 
Cruzin said:
I just read my last post and it sounded prety hoaky. But just remember some great cleaners have been found in the strangest places. Try cleaning gold, silver or brass with a bit of spit and cigarette ashes. Quite amazing!
Click to expand...

I think "Ask Heloise" made a career out of it. :D

My favorite, discovered quite by accident, is cleaning the bottom of copper clad pots (Revereware) with Ketchup.
 
Cruzin said:
Just gave me a thought; has anyone ever used Arm & Hammer tooth paste to polish metal? It's claim to fame for cleaning teeth is baking soda.
Click to expand...

Colgate baking soda and peroxide works wonderfully on sterling jewelry, so ya never know...

Also, S100 engine brightener really improves the look of oxidized aluminum engine bits and doesn't evaporate off.
 
Last edited:
Interesting stuff guys !

I too was curious about the soda blasting; while the engine is all together. I dunno if it is such a good idea or not - but if I were to do it, this is how I would go about it (On an airhead...)

-Remove the front engine cover, and tape cardboard around all the vent holes; re-install.
-Remove the airbox, top engine cover, fuel lines, and carbs. Plug the intake ports with a sock or something. When blasting near the starter, use a piece of cardboard to protect the starter.
-Blast away
-'Rinse' with a lot of compressed air, followed by a wipe down with WD40 or whatnot.

Thoughts ?
 
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