My CX500 project rumbles on and the engine is stripped and cases ready to go for aqua/vapour blasting. The trouble is : what to do with them once they’re all nice and clean? Conflicting advice says to leave the metal bare but having gone to all the trouble of stripping it all down my worry is that after being run a few times tarnishing will set in and the engine will look crap again. Others advise clear lacquer.
I’ve gone this route before and have had problems with the surface finish starting to yellow. Then there’s painting, but which paint to use? Most seem to require baking on at high temperatures for an hour or two. Will just running the engine be enough to cure the paint? My previous solution of using an old Baby Belling cooker for small parts is okay but engine cases won’t fit! Plus I’m concerned about warping and buggering up the gasket seal.
I can’t be the only home bodger in this dilemma. Are we forced to use the professionals at project-busting costs or can a good result be achieved in the shed? Don’t even suggest using the kitchen cooker. Tried that once – not a good idea unless you’re single and live alone!
Simple Tips to Protect Engine Paint
There was a reason why the Japanese manufacturers painted the alloy parts originally and that was because it is not as durable as other aluminium alloys. Unfortunately, the painting process they used was only designed to last for a few years before the bike was scrapped. You will need to use some sort of protection.
As you say, the lacquers available for home application are no good because they discolour with the engine heat. I do not think you will ever get a truly long-lasting finish using home-applied paint, but you might be content to re-apply the finish every few years. The best result would be produced by a professional as you might expect, but this is not cheap.
I have had pretty good service by spraying WD-40 on to aqua-blasted alloy from time-to-time. It’s very cheap and convenient but not as new: and I know that matters to many restorers.