Holley Carb. plating

[68goat]

Which method would one use in replating a Holley carburetor to the original finish, which is a gold irridite type finish. Also, are these carbs aluminum or pot metal??

[mcaswell]

Yellow chromated zinc plate - see http://www.caswellplating.com/kits/zinc.htm

Carbs are usually zinc die cast.

[68goat]

What type of surface prep is preferred for this, (ie) polished, glass bead blasted or tumbled with ceramic media??

[mcaswell]

If you want a shiny surface, you need to polish first. If you want a satin finish, glass beading works well. Either way, as long as the part is clean, zinc will apply readily over existing zinc.

[shoprat]

How big a kit would be required? What is the physical size limitations of the 1.5 gal kit?

[dfarning]

Originally Posted by mcaswell

If you want a satin finish, glass beading works well. Either way, as long as the part is clean, zinc will apply readily over existing zinc.

If you bead blast zinc die-cast, you may want to put the part in a pan of boiling degreaser after blasting. Maybe I am working with older (and poorer) die-cast than your holly, but I have noticed that bead blasting tends to embed glass beads in the casting surface. I use #80 glass beads at 50-60 lbs of air pressure.

A good rolling boil seems to work out the beads pretty well. If the part has taken on beads, you will get a fine sandy layer on the bottom of the degreasing pan within a minute or two. The sandy looking stuff is cracked beads.

I like to lift the part out and let it drain several time at different angles to rinse the beads out of the jets. Seems to work better than trying to blow out each jet individually with high presure air.

Keep us posted on your results. There are a few of us working with carbs.

[customcab]

Hi. First time poster here and I too have a question concerning a Holley Carb. I want to restore the original coloring to the body and bowls. The carb is in good condition but the color is gone. It had some very light scaling in the top surfaces, which I bead blasted to clean. Are there any other cleaning or prep steps that are critical before dipping in the yellow cromate?

Thanx, Phil

[awdmh]

I'm new and curious, also. I have the chromate, is it necessary to replate? Other than blasting, what steps are needed before the dip in chromate. thanks!

[dfarning]

If I have a good layer of zinc for the chromate to adhere to I just activate with an acid dip for a few seconds. If the zinc does not look good I put down a thin layer of zinc before the new chromate.

Dave

[awdmh]

What kind of acid?

What kind of container do you put the chromate in?

What temperature do you use for the chromate?

What ratio of distilled water to chromate? The container info was vague.