Plating - injector lines and other small things

[Novamonte]

I have taken the cylinder head off my 1966 M129 (250) engine to replace the head gaslet and plan to replate some of the stuff under the hood now that they are anyhow off (injector lines, steel pipes for coolant, various brackets etc). I heard somewhere that the yellow cad plating didn't come into use until later and that zinc plating was used in 1966. Can anyone confirm this? I found some yellow on the linside of the little blocks keeping the injector lines, so i am not certain what to make of it.

[stickandrudderman]

Yellow it is.

[ejboyd5]

I heard somewhere that the yellow cad plating didn't come into use until later and that zinc plating was used in 1966. Can anyone confirm this? I found some yellow on the linside of the little blocks keeping the injector lines, so i am not certain what to make of it.

Yellow cad began to make its appearance around 1956 on some Mercedes-Benz and Bosch components.

[mdsalemi]

Novamonte,

Both Zinc plating, and Cadmium plating, result in a silvery finish. Cadmium is nearly without equal in plating ferrous metals, and zinc is a distant second in terms of longevity.  However, because cadmium is quite toxic and the process can be an environmental problem, it has fallen to the wayside around the world…and may even be nearly impossible to find in Sweden and EU countries.  It is limited in the USA but you can find it if you look. I've recently seen that some purists call zinc plating as a replacement for cadmium "copy cad" and had to laugh at that.

The gold coloring comes from a phosphate or chromate "wash" applied after the plating and adds both color and an additional measure of protection.  The wash can be applied to both zinc and cadmium plating.

http://www.delsplating.com/cadmium-plating.html
http://www.chemprocessing.com/finishes/cadmium-plating.html

Unlike chrome plating, neither zinc or cadmium is [very] costly. It's done in batches, and the cost is usually per batch, not the pieces in the batch.  It does not require a lot of hand work like chrome.

[Garry]

Cad plating is very nice when done.  Agree with Michael, hard to find places that do it any more and thus charge a premium.  Here is a cad plating example for a 1965 from my car.

Garry

[Basil]

Looks beautiful. !!

[Novamonte]

Gorgeous indeed! I wish I could make my car look that nice under the hood. I will speak to the plater and see what can be done. Cad plating has been banned here for years. Perhaps yellow chromating over zinc?

[garymand]

How much does it cost to get all the tubes and rods aound the valve cover plated? I've been afraid to start, where do you stop?

[Novamonte]

I will let you know once I get the årice from the plater.

[mdsalemi]

Gary,

It will be considerably MORE costly for Novamonte in Sweden to get plating done, (I would guess) than it would be for YOU in SoCal.

Two places to check are Burbank Plating http://www.burbankplating.com and Prime Plating in Sun Valley http://www.burbankplating.com

Both of those places do true cadmium plating.  I've used Prime in the past and others here have used them as well.

It's done in a barrel.  It might cost, say, $150 for the first part; then $0.50 for the second part…get it?

Usually no more than a couple of hundred dollars to get it all done.  Fill up the barrel, and call your friends. 

[garymand]

I'm up in Nor Cal, I work in Sacramento and live near Auburn, up by 49'r.  Any know resources in Sac?  That's reasonable.  I'm having a lot of fun driving the car and adjusting the FIP right now, Maybe next month.  It would be ice to have a little of that bling going on under her hood again.

[wwheeler]

Maybe this has been discussed prior, but when did Mercedes use yellow CAD and yellow Zinc? I thought that yellow CAD was used early but was phased out in the 60s in favor of zinc because of the toxicity.

Another benefit to CAD plating is that the coating thickness is much less than zinc and therefore will not effect fasteners with close tolerances. Another consideration when considering the type of plating.   

[Novamonte]

I just picked up the parts from the plater. It was basically all things under the hood/bonnet that are supposed to be yellow (injector lines, CSV line, coolant lines, various stuff on the intake manifold, brackets, bolts and nuts and the thing on the intake where coolant warms the air etc etc). It looked fantastic and I found the price quite reasonable - SEK 400 (about $60). It was not done in a barrel - every piece was mounted on hangers as there will otherwise (according to the plater) be stains where a part is in contact with another.

I now wonder whether this good look will last or if I should cover the pieces with clear coat before I put them back? Any thoughs on this would be appreciated.

[mdsalemi]

If you could find a clear coat that might last, I'd say yes. I think spray-on acrylic might not last; I don't think most spray clear coats would hold up to heat and vapors in the engine bay. Clear powder coat might be better, but then you might have to spend a lot of extra money on this, probably a lot more than the plating itself!

I've seen more than one car where the owner has dispensed with cadmium or zinc plating on these engine bay parts, and instead had them painted professionally with a gold color match. It kind of stands out if you know what you are looking at.

Anybody with other experience here on this? I think it's a good topic!

[hkollan]

I now wonder whether this good look will last or if I should cover the pieces with clear coat before I put them back? Any thoughs on this would be appreciated

Excellent original cars often still have most of the yellow chomate/cad plating intact after 40-45 years.
Why improve on that?  With the use that these cars usually are exposed nowadays with no winter use and salt exposure,
it will probably last another lifetime. If not repeat the procedure in say 20 years.
After a while  the bright and shiny  plated  parts will develop  a minor patina with a slightly duller look, (perfect in my opinion)
so that even an expert will have problems determining if the parts are restored or just well kept originals.

Hans

[zoegrlh]

Had me lines re-plated a few years ago locally (Hayes, Virginia), asked them to please not keep line in plating vat too long, I did not want the bright yellow look, wanted a more lighter look of patina.  They did an excellent job, and my lines look as if they were not "re-plated" but new with a few years wear.
Bob

[mdsalemi]

Excellent original cars often still have most of the yellow chomate/cad plating intact after 40-45 years.

I only WISH my plating has lasted that long! Even with a cushy, comfortable, if not pampered life, the once bright plating on the engine bay parts has faded, and it's only been 12 years! Alas, it was done with zinc not cadmium…had I only known at the time that cadmium is preferable if not longer lasting, I would have insisted the restorer find cadmium. I had no idea.  

[scoot]

I'm about to go down this path (perhaps) and live close enough to Burbank Plating to use them.  What I'm wondering is what level of cleaning do I need to do on injection lines prior to taking them in...  There is no way the line fittings are going to be removed so does that matter? 

thanks
Scott

[wwheeler]

The deal with fittings is that it will not plate very well in the space between them and the tubing. However, most the time the fitting is either stuck at the end or it floats around. If it floats around then some plating will deposit itself on the tubing all over. If it stays stuck at one end, the plating will be weak and dull under the fitting at the end, but will not be visible. But nothing you can do about the fittings.

Plating to me is like body work. The better prepared it is, the better the result. Platers use acid that will remove old CAD and zinc finishes and surface rust. It will NOT remove grease or paint very well. So I always clean parts as best as I can before sending them off. Parts left with grease and paint on them will be noticeable flawed and the plater will not accept responsibility.

[scoot]

Instead of plating I decided to clean them.  At this point I don't even know if the engine will run (ever) again.  So I am cleaning the lines in a tube filled with Evaporust, then blowing the insides clean with diesel and compressed air, then with carb cleaner and compressed air, and then with compressed air.  I am lightly oiling the outside of the lines.   Out of the 2 that I have done, they look quite nice compared to before.  See pics.

[County Guy]

Sweet.  I'm inspired to do the same.

Lockie

[scoot]

Sweet.  I'm inspired to do the same.

Evaporust is one of my favorite products.  It works wonders on what I assume to be crappy chrome and then sometimes it turns out great, and sometimes it just turns out better.  It does remove some of the yellow color, but I don't know if that is just the color removed or all of the cad plating with it.   The only suggestion I've heard of for preserving the yellow color is 0000 steal wool with mineral oil, which I doubt would work well on things that look rusty...

The blue drain tubing was just a lucky find at the hardware store.  It works great on strangely shaped objects like an injection line.   Previously I had used 4" PVC tubing capped on both ends for items like W111 tail lights.