Sachs engine finish

[peter kane]

I have a few questions about the finish on the Sachs engine and some other aluminum parts.  Years ago I broke a few fins off the jug of my 70 Six-Day and put them aside with the thought that someday I could have them welded back on.  I went away for a few decades and while I was gone my brother threw them (and a bunch of other good stuff) away when he was nosing through my prized possessions in cellar - thinking they were junk.  Yesterday I won my first-ever ebay bid on a replacement jug.  Twelve bucks!!!  How good is that I ask?  

I don't have the jug yet but from the pictures and what the seller told me it bears the scars of being in weather for a long time. In restoring this gem I want to bring it back and make it look as close to what it originally looked like but don't quite know what to do.  Bead blast?  Walnut shell blast? Dip?  Polish?  None of the above? You get the idea.

From what I recall these engines had almost a cadmium like finish looking brighter than galvanized, with the same type of satin/dull finish, but duller than bright steel - and certainly not the polished look of the finishes on Asian bikes.  Am I close, and how do you get it back to that?

Also, on the hi-breather frame, was the aluminum air box base bright?  [What are the oval-head slotted screws for on the back side of the aluminum air box base?]  And can anyone tell me anything about spoke, control and all other bare metal finishes.

I figure that while money is really tight I could be doing stuff like this that doesn't cost me anything since I have a bunch of polishing and spray equipment.  

As always - thanks!

Peter Kane
V3442
Plainville, Massachusetts
[email protected]

[dkwkid]

I bead blasted the barrel and head. I left them bare aluminum(I think that is the way they came from the factory.)As far as the cases I found a rattle can paint by Duplicolor. It is engine paint named cast aluminum.High temp and supposedly resistant to oil and gas.Looks pretty close to stock.

[peter kane]

Eeeeeks- paint on the cases?  I don't know if I'd want to go that route since I don't recall a flake of paint on engine in the first place.  Anybody else have an opinion on this.

Peter Kane
V3442
Plainville, Massachusetts
[email protected]

[Doug Wilford]

The cases are painted,  the duplicolor he is talking about is a very good match and bead blast the head and cylinder and leave at that.

[Johnno]

Probably been asked before, but does anybody know of a UK supplier of Duplicolor high heat paint?

jd

[peter kane]

Try this JD,

167-169 New Chester Road
Wirral
Merseyside
CH62 4RB
United Kingdom

Tel: 0151-643 1171
Fax: 0151-643 1483
http://www.autocolor.co.uk

Peter Kane
V3442
Plainville, Massachusetts
[email protected]

[Johnno]

Thanks for the swift reply Peter.

Have you any advice on getting the old paint off the casings. I've got a 125/6b engine thats been lying in bits for many years so some of the paint is bubbling up and flaking.

jd

[James]

Jd, use a good chemical stripper on the majority of the flaking paint if you have layers of it. Aircraft Stripper is what I prefer here in the U.S. I think you can get better strippers in the U.K. as well. Finish by bead blasting. If you only have one layer or so of paint-skip the chmical stripper and go straight to bead blasting.

James

7" and 4" travel? Hmm-that makes 11" Hey! I can live with that.

[Johnno]

does bead blasting cause any damage to the definition of the writing on the outsider of the casing?

jd

[Doug Wilford]

I cover the Sachs plate on the right side cover with masking tape, that is the only one that bead blasting will screw up.

[john durrill]

jd,
 Make sure all the bearings are out of the cases or sealed well. I have the best luck with hot soap and water after blasting to remove all the dust and fine particles imbeded in the metals surface. Hot as you can get it and still handle the parts. Then rinse in hot water and coat with a water displacer like CRC or WD40. The kick shaft bush and other hard to get at places will hold all kinds of particles that will cause serious damage once the engine is together and running. Dish washing detergent is good but i like the Johnson and Johnson baby shampoo the best . It leaves no residue and cuts oil and grease well. We use tape on any surface we dont want blasted like base gasket surface and center case gasket area.
John D.

[peter kane]

jd,
Don't do what a guy did on the Vinduro site.  A week or so ago there was a long thread about cleaning metal surfaces, more specifically engine cases.  I guess this guy put everything in the dishwasher and let it rip.  The parts reportedly came out clean but he couldn't – it seems that the dish washer no longer had it's 'fresh clean smell' that his wife remembered, instead, it smelled more like an waste oil receptacle or a greasy old boot.  I'm not sure if the dude is now living in the garage, his car, or the dog's house, but it would probably be wise take heed to John D's direction.  I learned a similar lesson a long long time ago with a brand new white porcelain kitchen sink that I not only stained with oil and stunk up the drain, but I chipped the sink in the process as well.  That was over 30 years ago and I still hear about it to this day.  Buy a plastic basin!      


Peter Kane
V3442
Plainville, Massachusetts
[email protected]

[Johnno]

Thanks for the advice Peter. I get enough grief for disappearing off to the workshop at every available opportunity so introducing engine parts into the kitchen won't be high on my priority list

jd