Hot Rod Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
331 Posts
Discussion Starter · #1 ·
I'm probably gonna get flamed for this, but when it comes to aluminum intakes and heads I love the way they look out of the box but hate the way they dull over time. I am seriously considering painting them so they look as good as the rest of the engine for years to come. Is anybody else doing this? Is there a better way to protect aluminum from dulling/oxidizing?

Like putting a Ford engine in a Chevy, people seem to have a strong aversion to me painting my heads and intake.
I would love to get some opinions and advise on this subject from all of you. I can't be the only one who hates the look of aluminum after it's out in the elements for some time.
Paint? No paint? Options?
 

·
Registered
Joined
·
4,259 Posts
Well the heads are mostly covered with brackets, exhaust, and such. Painting the heads with lets say VHT clear or any coating is going to hold in heat and may yellow over time.

The acessory brackets and the exhaust can be painted. As for keeping it shiny there are aluminum cleaners you can spray on a "next to final step" sponge and then wipe down the aluminum that are great at cleaning in a hurry.
You just need to do it every other oil change or 6000 miles.
Steps: Degreaser, water, rag wipe down dry, repete, aluminum/chrome polish sponge, microfiber cloth.

Bit of a hassle. But its not that bad if the acessories come off easy and you use a spongs/rags to get into the hard spots.
 

·
Registered
Joined
·
225 Posts
I like plain alum but it corrodes fast around here. Paint or corrosion can be a thermal barrier. If it's a carburetor engine then a bad jet change can mess up your paint. I'm more likely to paint heads and not the intake. They have ceramic coated intakes but not sure how well they hold up to gasoline spills. Polished is another option, if you don't mind spiffing it up now n then prob.

Also electrical grounding is something to consider when painting engine parts.
 

·
Registered
Joined
·
15,314 Posts
Aluminum is simply not easy to paint. I have no problem with the idea of painting it but it takes a lot of prep work compared to steel or iron.

Aluminum develops a corrosion layer faster than you can read this. For any paint to stand a chance of sticking the corrosion layer must be removed. This is done with you always wearing gloves before touching the part and always renewing those gloves between operations. This protects your skin but more importantly protects your project from oils and chlorates (salts) present on your skin. Start first with a solvent degreasing and rise. Then with a very dilute acid wash with a clean small brush, can be vinegar, followed by through rinsing with deionized water and prompt clean compressed air drying followed by application of self etching primer that is fully allowed to cure. Then color coat paint can be applied with reasonable assurance it will stick for a few years. Problem with engines is heat, oil, fuels and glycol coolants all stain or dissolve single part paints like what comes out of rattle cans. It really takes a two part paint like polyurethanes with separate base and hardener to survive under the hood as they are not dissolvable by coolants, fuels or oils so they maintain luster and structural strength for a very long time.

Yes electrical grounding is an issue, especially if you’re running a capacitive discharge ignition. Here external grounding of head’s and intake is a good idea. So where ever a ground wire attaches the paint needs to be removed to assure a conductive bond is made.

Bogie
 

·
Registered
Joined
·
331 Posts
Discussion Starter · #5 ·
Aluminum is simply not easy to paint. I have no problem with the idea of painting it but it takes a lot of prep work compared to steel or iron.

Aluminum develops a corrosion layer faster than you can read this. For any paint to stand a chance of sticking the corrosion layer must be removed. This is done with you always wearing gloves before touching the part and always renewing those gloves between operations. This protects your skin but more importantly protects your project from oils and chlorates (salts) present on your skin. Start first with a solvent degreasing and rise. Then with a very dilute acid wash with a clean small brush, can be vinegar, followed by through rinsing with deionized water and prompt clean compressed air drying followed by application of self etching primer that is fully allowed to cure. Then color coat paint can be applied with reasonable assurance it will stick for a few years. Problem with engines is heat, oil, fuels and glycol coolants all stain or dissolve single part paints like what comes out of rattle cans. It really takes a two part paint like polyurethanes with separate base and hardener to survive under the hood as they are not dissolvable by coolants, fuels or oils so they maintain luster and structural strength for a very long time.

Yes electrical grounding is an issue, especially if you’re running a capacitive discharge ignition. Here external grounding of head’s and intake is a good idea. So where ever a ground wire attaches the paint needs to be removed to assure a conductive bond is made.

Bogie
Thank you so much for your response and information on this! Now I know how to prep 'em for paint.
 
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top