Replating an original C1 unvented hi-horse oil cap 1959

[Ian G.]

I managed to land myself what I think is an original unvented hi-horse oil cap with D-shaped depressions for my 59. I want to get it replated in Cadmium, but John Degregory indicated it might ruin the Cad chemicals of the plater and I definitely don't want to upset the guy or get charged extra for it. I let it sit in Lacquer thinner overnight so it could clean out the insides a bit, and I can attest it took hours to fully drain on its side. so I can see how the chemicals could easily leak between tanks. I admit though, I don't know how the cad plating process works.

Does anyone know someone who restores these or can suggest a method to prep it for plating? I could drill a hole inside and then twist the clip over it I suppose. Below is a pic of it. Would Dec 58 car be considered "early" or "mid" for purpose of the D-shaped indentations vs the parallel line caps?

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[Richard M.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Ian, John is giving good information. There is likely a thick residue still inside the cap which could contaminate the chemicals.

For example, here is a vented cap from a '59 I tried to clean. Granted it's not the same configuration but you can see what years of use does. The oil vapor turned into a crusty compound.

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In your case I would just continue to flush it. Maybe carb or brake cleaner could help loosen anything left inside. Another idea might be to use oven cleaner spray by letting it liquefy before pouring it in the opening until full. Repeat.

The Cad plating process is quite expensive for a single item so if you have other items needing plating it will help offset cost, hopefully.

Rich

[John D.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

IAN, I think of our fellow man. Sometimes more than myself. I would feel really bad if the owner of the plating company blew mega bucks on chemicals just because of an oil cap.
I make them look decent by cheating but I tell the customer before hand. It's called Krylon dull aluminum. Then I hit the cap with a flat coat of clear. Presentable. John

[Ian G.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Thanks Rich, Yeah I have a bunch of bolts, plates and brackets I'll be doing at same time. This cap is unvented so you'd think the residue can't be too thick I hope. I want to avoid drilling it if I can but that's my next step if I can't get it clean by letting it bath in cleaner. When I let it bathe in lacquer thinner it did not discolor it as far as I could tell.

John, is the problem that the chemicals themselves can mix between tanks or the possibility of oily residue inside? I assume its the mixing of mineral water, pickle and cad chemicals that would leak out from the cap. If its just the residue, I'll let it sit in naptha, acetone or mineral spirits or something clear so I can tell if any discoloration happens if its just the residue and make sure its actually clean inside without drilling.

I'm also thinking to myself I don't particularly want a cap back full of arsenic water either so maybe the hole drilling is called for no, matter what.

Thoughts? I'll probably just go with my repop vs spray the cap with paint I think

[Edward J.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Ian just a thought, can the steel wool stuff inside cap be removed and the cleaned and re-installed after the plating? If your just going to use for judging reasons remove stuff and clean out and have plated.

[Richard M.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Edward, It's a sealed cap. Not sure what's inside though.

Ian, Maybe they could just plate the outside topside down and mask the opening to prevent chemicals from going inside it. Maybe ask them?

Rich

[Edward J.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Rich, I was looking at your cap thinking it was similar. Oh. Well.

[Ian G.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

I think it is actually hollow. I could hear the lacquer thinner sloshing around inside. Thanks Rich, I will ask them that, but these cad guys in california do mostly big military jobs I think and I'm honestly happy if they will work with me at all lol.

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[Dan H.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Years ago, we used to pry the bottom lip up 90 degrees so we could remove the bottom insert, get the top plated and peen the lip back over the bottom piece.
Dan

[Ian G.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Thanks Dan, I was thinking about that. I've left it submerged in naptha for a few days now and don't see any discoloration. I'm feeling like its safe.

[Keith R.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

Before you go to any extreme amount of work or cost, you should first verify that it's an original cap and not an older reproduction. The rivet on the bottom should be "doughnut" shaped; there should be three evenly spaced narrow detents or crips along the lip of the cap; the "O" in the oil stamp along the "D-shaped" depressions should fade into the depressions. The lip is thinner on an original vs. a reproduction cap. The cap should have a sharp 3/8" radius vs. the sloping 1/2" radius found on passenger cars. I think that you might have a passenger cap or an older reproduction.Refer to page 193 and 194 of the TIMJ.

[Patrick B.]

Re: Replating an original C1 unvented hi-horse oil cap 1959

You can buy a home plating kit from Eastwood for zinc plating and it is easy to do. I think zinc plating polished with Scotchbrite looks pretty much like silver cad, and you can plate your bolts and hardware with this kit too.