Cylinder and engine paint questions.

Discussion in 'Half VW' started by 12notes, Oct 29, 2019.

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  1. Oct 29, 2019 #1

    12notes

    12notes

    12notes

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    I'm stripping the 2-3 layers of paint (orange, silver, and red) off the Global 1/2 VW I'm close to assembling for the Hummelbird I'm building, and wondering what needs paint and what doesn't. The cylinders are steel, so I know I need to paint them. Cylinder heads and valve covers are aluminum, the whole engine weighed 85 lbs, not sure if the block is aluminum or magnesium. Do any of those need to be painted, and is there a recommended paint? I seem to recall Pops stating the valve covers should be painted black to help with heat dissipation, I assume black paint on the cylinders would be good too? I have a can of VHT black engine enamel which is rated for 550 degrees, is that good enough? Should I use primer, or will the paint be fine as is?

    I'm not building a show plane, so basic protection is good enough for me.
     
  2. Oct 29, 2019 #2

    TFF

    TFF

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    I would go black with everything. How thick is up to you. Black is better for heat dissipation. How much better is...
     
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  3. Oct 29, 2019 #3

    Pops

    Pops

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    Bob Hoover says to use a light coat of enamel and thin with gasoline for a flat finish for the case.
     
  4. Oct 30, 2019 #4

    pictsidhe

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    I used to use a cheap brushable product called 'pot black' in the UK for motorcycle cylinders. I could feel increased radiation after painting an aluminium cylinder. It was thin stuff with plentiful solvents. Thick paint will reduce heat transfer, though not a huge amount. I used to go as thin as would be uniformly black. Worked fine for me, didn't seem to be prone to rust on the few steel bits I painted. I never primed. Just make sure the surfaces are good and clean. Bead or sand blasting to get oxidation and old paint off is a good idea if you can.

    Pretty much any colour paint will increase heat radiation. Heat is radiated at a wavelength where just about all paints are quite 'black', even visibly white paint. So, feel free to go psychedelic! Some metallics break that rule.
     
  5. Oct 31, 2019 #5

    12notes

    12notes

    12notes

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    Thanks everyone. I'll paint everything with rattle cans of VHT black engine enamel, once I get the rest of the paint off. I've already used 3 spray cans of Aircraft Remover, had to order more to get the small amount left on the cylinders and heads.
     

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