POR-15 Ceramic Manifold Paint - no good

90sc35thann

Registered User
I am kind of mad at myself. When I had my engine out a couple of months back I got cheap. I received a quote of $300 to have my manifolds jet coated. I thought that was nuts. I did some reasearch and found a ceramic manifold coating from POR15 that was rated for 2000 degrees. I had always been happy with their product so I thought heck I'll give it a shot. I bead blasted my manifolds and then washed them in trisodium phosphate (A technique that is used during the powder coating process for bare metal to insure proper adhesion) to insure there was no oily residue left behind and then rinsed very well. Well I was underneath the car performing the first oil change this past weekend and there isn't a stitch of that coating left anywhere on the manifolds. The manifolds are still nice and clean but now have surface rust on them. I used three coats on the manifolds and allowed 24 hours between coats. What a joke! I wish had I hadn't gotten cheap and just had them jet coated.


n a good note I can say that there engine block paint rocks the house.
 
Trisodium phosphate is a really good cleaning agent but to prep the metal for the best adhesion an Iron Phosphate would have ‘etched’ the surface correctly allowing improved bonding. Just my opinion.



Chief
 
Trisodium phosphate is a really good cleaning agent but to prep the metal for the best adhesion an Iron Phosphate would have ‘etched’ the surface correctly allowing improved bonding. Just my opinion.



Chief

I know you do quite a bit of finish work so I know you are probably spot on. I figured after bead blasting, the surface should have been etched enough and that the trsodium phosphate would simply remove any excess oily residue. Live and learn. Either way that product shouldn't have flaked off like it did, IMO. :)
 
When I used factory manifolds for my old turbo setup. I shot them with 2000degree VHT. Looked like the day I did them after a year.

I did this right over rust and everything else. I just shot them with brake cleaner then paint.
 
Last edited:
When I used factory manifolds for my old turbo setup. I shot them with 2000degree VHT. Looked like the day I did them after a year.

I did this right over rust and everything else. I just shot them with brake cleaner then paint.

I used the Eastwood brush-on manifold coating that looks like bare blasted iron. It has lasted over a year and looks pretty good, except for one spot where a coolant hose weeped onto the manifold. That spot is back to regular old rust. Oh well. Can't see much of them anyway.
 
Back
Top