Solex Manifolds

[304065]

I would be a bit hesitant to remove the studs for a mag casting, not to mention time consuming. What about post plating wire brushing and spot black oxide treating?

I was going to disagree that the studs were black oxide, but I just bought an NOS maniofold with the stick still on it. There is definitely not plating on the studs and a hint of black oxide and mostly surface rust. Interestingly, that funky shiny rainbow plating we are finding on underside of the float chamber on non-NOS manifolds , on this NOS one has corroded all over like all the rest of mine. Must be a pretty unstable plating or base material.

If you don't pull the studs you can't surface the flanges. Given the amount of corrosion on mine I think that's a necessary step. Also, 40 year old steel studs are often weakened by DPO gorilla torquing, such that they shear in half when clamp load is applied. Better to face that before they are plated IMHO, although I agree that breaking the manifold isn't good either.

[rcnagel]

I called Van Nuys plating which does provide "clear Cad" plating, they won't touch magneseum. I contacted the National Plating Associations or something that gave me ten companies in California who plate magneseum. I'll let you know what I find. It may be the same process.

[304065]

I have been following up on the chromate and pickle route.

Made a few calls, it seems that the gold VW engine cases are done using either Dow #1 or Dow #20. Dow #20 has been replaced by another process with the same effect.

You wouldn't believe the level of secrecy associated with these processes-- guys playing hide the banana with the information. Maybe it's because this is a coveted "concours" technique and nobody wants to give away information.

In any case I had a further conversation with my plater, I'm going to have the originals bead blasted and polished and then flash-plated with copper as a base for cad and chromate. Now I just have to source somebody to do that. . . somewhere the guys at the Factory, long since gone to their just reward, are looking down and LAUGHING at us. . .

[kenikh]

I seem to recall someone having two right manifolds looking for a left. I have two lefts and need a right. Anyone remember who that was? I can't find it.

[304065]

Update: I spoke with my plater, he wants to do flash copper over the magnesium to provide a better base for cadmium and chromate.

My ORIGINAL manifolds are off to be blasted, surfaced and to have the studs removed. When they come back they will be flash plated and then go with a bunch of other stuff to the cad shop. What a process this all is!

[rcnagel]

I seem to recall someone having two right manifolds looking for a left. I have two lefts and need a right. Anyone remember who that was? I can't find it.

I thought it was me, but I have an extra left (drivers side) as well. I have an extra right but part of casting is broken off. Some machinist at some point made a pretty decent retrofit. You can have the manifold and retrofit bracket if you want it. At least it could be a place holder.

I also have the better part of an entire right side solex setup that I will be selling soon.

[304065]

Plating update (sorta)

I sent mine to Ollies to be blasted, tumbled, have the studs removed and flanges surfaced. As you can see, the manifolds are definitely bright magnesium under the chem film and corrosion.

Next step is these will be plated, flash copper at first and then cadmium with a chromate conversion coating to resemble, if not perfectly match, the finish on the originals. Then the studs get tumbled and black-oxide coated and go back in.

A lot of work but required if you want it to be original appearing.

Also, what junior engineer designed these outer manifold tubes? Unlike the later black Zenith manifolds these are not a straight shot, but curved tubes that have a strange oval port cross section. I wonder what they do on a flow bench? I'll see what I can find out.