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Bonding AL (Cast Al to Billet Al)

2007

Hello All,

I'm trying to get my self out of a problem I'm having with a car build. I have an cast Al valve cover and a Billet Al oil filler tube. The valve cover itself is powder coated. My first idea was to have them both welded together from the inside of the cover while holding a cold rag on the outside so not to damage the powder coating with the heat. No one seams to think this is possible. One local welder said I might think of using a bonding agent, like Devcon, or something? My fear is failure. If the bond fails it will fall into the valve train, and damage if not destroy the engine. I'm looking for a bonding agent that can take the heat, and oil bath from a hot engine, and not fail. Temperatures in a valve cover are not what they are inside and engine, but still quite hot.

Thanks,

Brian Frankson
Car hobbyist - Raleigh, North Carolina

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First of two simultaneous responses --

Why not weld it and have it re-powder coated as a unit? Should only cost you a hun, how much would it cost to fix the damaged engine if an adhesive fails? You could always use available engine "dress-up" equipment and you wouldn't have to worry about this "custom" design going bad on you.

Sheldon Taylor
supply chain electronics
Wake Forest, North Carolina
2007

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Second of two simultaneous responses -- 2007

The engine compartment of a car is a very stressful environment subject to wide temperature variations.
You estimate that the consequence of failure would be very expensive.
I suggest that you have two alternatives
1/ Thread the parts and make a mechanical joint.
2/ strip the powder coating, weld the parts and re-coat the complete assembly.

Geoff Smith
Hampshire, England