WA1 Exterior Finish Color ~ Mystery Solved?

rambos_ride

Me thinks partially!

First, this really only covers the aluminum parts - since other metals can be plated to provide for corrosion protection.

I was pulling apart my other donor carbs to get a look at the needles/seats/floats etc and get the best parts.

To my surprise these carbs look pretty near factory original and didn't appear to ever have been rebuilt.

The piece in the center is from one of the original carbs, left and right are pieces I cleaned and painted the exterior.

Looking at the picture you can see the underside of the top of the original float bowl clearly is gold tinted. I scratch tested and this is a tint from a chemical coating/conversion process - not painted on.

The inside surfaces of the bowl and mating surfaces shows the same residual gold chemical coating!

My assumption now is the chemical coating just wore off the outside over time....







So what does all of this really mean?

On this rebuild - not too much, don't have the extra money to experiment with the chemical processes right now :mad:;)

Although the Carb Renew paint we're using is fuel resistant - I don't think it's fuel proof and in that mindset I have only painted the outside surfaces of my carbs, this leaves the inside and mating surfaces without any real corrision protection (which would suck over a long period of time in certain environments)

In the future and if I were doing a full-restoration or working on a customers parts I'd figure this process out to provide for an original finish and complete corrosion protection on the aluminum parts.


Summary

To get a chemical coating like this it HAS to be a process of etching with something similar to Alodine. I am SURE with a little more research and some testing a chemical dip process could be documented to restore these beauties to their full former glory!

rambos_ride

Hudson308 wrote:

There has to be some plating process to restore this finish, Dan.
There was a set of three stromberg carbs at a swap meet last weekend that were 24k gold plated. Of coarse, you & I would never do that, but they were sure unique, and illustrated the fact that these parts can be plated many different ways.

Yes, you can plate aluminum castings - but the original finish these WA1 and on most older carbs is a chemical type finish, no plating or ceramic coating like the have these days.

Here's an example of an aluminum aircraft piece prepped with Alodine before primer ~ it shows a similar coloring to what the inside of the carbs I have look like.

Browniepetersen

Alodine to my way of understanding chemically etches the metal and leaves a finish that holds up better to corrosion. Most of the alodine processes I have seen (we do it at work) is a two phase process with cleaning inbetween. Once the part has completed the process it is inspected and touched up with anodizing. I wonder if anodizing the inter parts of a carborator would do the trick? I wonder for how long?

rambos_ride

These look nice - check the color...

http://cgi.ebay.com/ebaymotors/53-54-Hudson-Jet-Twin-H-Carter-Carburetors-2013S_W0QQitemZ310151075493QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item483671d6a5&_trksid=p4506.c0.m245&_trkparms=65%3A12%7C39%3A1%7C72%3A317%7C240%3A1318