Media blasting materials, k member, steering box
@Murray, these pics might help illustrate what 69 M Code is trying to explain.
In my industry it's called "outgassing," the process of pre-heating all parts for a longer time and at a temperature higher than that used to cure powder. What it does is bring any trapped air bubbles, impurities and chemicals in/on the metal to the surface where they can be blasted away as part of the prep work. Aluminum shows the results even more dramatically than steel does, which mainly turns a blue / purple color while any grease just turns blacker.
What's most telling about this particular valve cover is that it was BRAND NEW, shipped direct to me from Jeg's by my customer in Oklahoma along with an air cleaner assembly. Aluminum is very porous and absorbs all kinds of gunk, especially oils. Steel doesn't absorb as much but heating it up turns its impurities into chalky dust instead of sticky grunge. Sometimes I even get out the big propane flame thrower with a 3 foot handle to speed things along on k-members, suspension bushings, etc.
@Murray, these pics might help illustrate what 69 M Code is trying to explain.
In my industry it's called "outgassing," the process of pre-heating all parts for a longer time and at a temperature higher than that used to cure powder. What it does is bring any trapped air bubbles, impurities and chemicals in/on the metal to the surface where they can be blasted away as part of the prep work. Aluminum shows the results even more dramatically than steel does, which mainly turns a blue / purple color while any grease just turns blacker.
What's most telling about this particular valve cover is that it was BRAND NEW, shipped direct to me from Jeg's by my customer in Oklahoma along with an air cleaner assembly. Aluminum is very porous and absorbs all kinds of gunk, especially oils. Steel doesn't absorb as much but heating it up turns its impurities into chalky dust instead of sticky grunge. Sometimes I even get out the big propane flame thrower with a 3 foot handle to speed things along on k-members, suspension bushings, etc.
