Split intake

Boy, that would be enough for me to tear the engine down and see what else is going on inside.
Why would block off plates be a big concern? It is/was a fairly common practice. No idea where the sand would come from, one guess would be the intake was blasted at some point and not cleaned that well after.
 
Chrome plating can cause hydrogen embrittlement. The sheet metal covers don't look all that thick but they would still have a shim effect that could cause stresses there when the bolts are torqued up. It would't take much of a step there to cause a crack on an old part like that. Especially if its one of the early ones that were kind of frail anyway.
 
The sand is aluminum oxide, IMO.
Just a guess, but moisture from exhaust entered through opening one side combines to make a corrosive mess.
I bought an intake from a well known vendor that had a hole between the heat riser portion and the vacuum of the intake. It had a similiar appearance.

With that much corrosion, I would replace it. Now

Karl
 
Chrome plating can cause hydrogen embrittlement. The sheet metal covers don't look all that thick but they would still have a shim effect that could cause stresses there when the bolts are torqued up. It would't take much of a step there to cause a crack on an old part like that. Especially if its one of the early ones that were kind of frail anyway.

Good point about the shim possibly causing a stress riser.
If the manifold is plated, we could probably forget about welding.
I thought I learned in school many years ago that hydrogen embrittlement really only affected ferrous metals like steel and iron. Just did a quick search on Wikipedia (which can be wrong) and found the following --
"In tensile tests carried out on several structural metals under high-pressure molecular hydrogen environment, it has been shown that austenitic stainless steels, aluminium (including alloys), copper (including alloys, e.g. beryllium copper) are not susceptible to hydrogen embrittlement along with a few other metals"
 
The sand is aluminum oxide, IMO.
Just a guess, but moisture from exhaust entered through opening one side combines to make a corrosive mess.
I bought an intake from a well known vendor that had a hole between the heat riser portion and the vacuum of the intake. It had a similiar appearance.

With that much corrosion, I would replace it. Now

Karl

Another really good point...
 
Chrome plating can cause hydrogen embrittlement. The sheet metal covers don't look all that thick but they would still have a shim effect that could cause stresses there when the bolts are torqued up. It would't take much of a step there to cause a crack on an old part like that. Especially if its one of the early ones that were kind of frail anyway.

Yep, the shimming could be an issue for sure. Pennies are a better way to go! ;)
 
Back
Top