High Temp Powder Blistering

[txtaco]

We purchased some silver high temp powder from pbtp and coated a set of 350 small block headers. The client brought them back to me and said the coating blistered up after 10 min of his engine running. The headers were sandblasted and cleaned with thinner. No Iron Phosphate was used. Any suggestions please?

[Harleydad]

You shouldn't clean with the thinner either. When I do high temps' it's blast only, no chemicals. Don't handle the parts without nitrile gloves.

[txtaco]

They were just wiped down with thinner before blasting to get all the grease off. After blasting they were just rinsed, dried, and preheated.

[baz]

They were just wiped down with thinner before blasting to get all the grease off. After blasting they were just rinsed, dried, and preheated.

what did you rinse the header with ? i never water rinse steel parts.
did you apply 1 or 2 coats of powder ? high heat powders don t work with multiple coats