Burnt engine

Zinc is a low temp metal, as Milr said is around 750 degrees. I did two weeks in a die shop that poured zinc dies and they kept the pots at 790 degrees.

It was better than the aluminum foundry I worked at.

 

Maybe I didn’t quite follow what you were saying but the way I read your post was basically that had the covers been a zinc they would not melt as quickly but since they were Aluminum they almost certainly melted

 

What was the name of the aluminum foundry?

 

I wasn't clear ... sorry ... I meant that there are zinc covers that would have melted at a lower temp which in many cases the engine may be recovered, being an aluminum cover, it melts at a higher temp and could have damaged the engine beyond any recovery.

I worked at a small foundry in Detroit back in 1976 for a few months then went to school for a few years and worked there until they closed in 1979, it was clapper and sons tool and die. They did both die casting and sand casting.

I also worked at a copper foundry for a few summers up in the upper where my grandparents lived, making trinkets and touristy things for vendors to sell.

 

Never heard of the place but this was before my time. I was just curious

 

I’ve also never seen or even heard of a valve cover being zinc so that confused me as well.

 

They were in business since 1949, small shop with about 35 people working there. The old man died, the sons retired and they just shut the doors. About 1990 someone bought the building and scrapped everything.Detroit at that time had something like 50 foundries, I think there are a dozen and a half left.

I seen a few gmc diesels with them, they warped and leaked but I understood from someone at Cummings a few stationary engines use them and they are die cast.

 

Are you sure about that?
I know some valve covers were steel with zinc plating for corrosion reasons but I have doubts that any valve covers have ever been zinc die casted.

 

I can't confirm or deny, but I do know that I've seen mfg's do the stupidest, most illogical things all in the name of saving a buck.