ET: Engine (Twin) Maximum temperature for baking castings

[oexing]

Greg, don´t worry about 170 degrees C , you can go a lot higher. 200 degrees C is BMW´s specification for valve seat and guides shrinking in. Look at aero engines max. continuous head temperatures, around 350 degrees F , stay below 400 F in climb .
As I said, put the heads in the oven at 250 degrees C for a few hours depending on smell/smoke remains . But first send your wife for shopping afternoon if you haven´t got an oven in your workshop - a good idea anyway for many uses !

Vic

 

[flxible]

When I prepped my cases and covers for paint, they went in the oven at 200-250F for 15 minutes or so, came out and all surfaces were wiped down, with clean white rags and lacquer thinner.
With I think, perhaps six cycles of this procedure, the clean rags showed progressively less oil/dirt, till with the last cycle there was no oil/dirt picked up by the clean rags after the wipe down was completed.
The parts then went back in the oven for another heating, and were sprayed black when they came back out.
And then went back in the oven with the heat on but door cracked open to off gas.
Best-
George

 

[Chris Launders]

Don't bother with heat, just soak them a couple of days in paint thinners