How long have you had the ute? Isnt it basically new?
Also I wouldnt be painting the insides of engine components like that, at least where I can see it its only coolant flowing through there, you didnt paint inside where the chain is did you? What paint did you use?
Some competition engine builders do paint inside blocks to help drain back and also seal in loose sand from casting but that is done properly and wont flake off and block your oil galleries.
And nothing like a stocko engine bay, but thats my 2c.