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Zinc/aluminum alloy treatment HELP needed:

2000

Need information. My carburetor internal parts are made of the same material, zinc/aluminum maybe magnesium alloy. The throttle valve slides inside the body wearing-out frequently. Question: Is there a coating/treatment that I can apply that would change the characteristics and make the two surfaces dissimilar enough to be able to wear longer? Something like Ospho [affil links] or other caustic treatment and then maybe polishing to improve lubricity. Is there such a procedure that I can try?

Thanks so much for your help

Pat

P.R.K [last name deleted for privacy by Editor]
- Gainesville, Florida

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Second request

Need to know what would be the best finish for Zinc/Aluminum/Magnesium alloy. My carburetor throttle valve wears too fast inside the throttle body because these two parts are made of the same alloy. Need to treat one of the parts (throttle valve) with something to reduce the wear.

Ideas: Chrome plating Anodize Acid dip Copper plating

I am not the expert so I could use a little help

P.R.K.
- Gainesville, Florida
2000

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If it were my part, I would machine it (undersize/oversize) and put 0.001 ± of electroless nickel. No post treatment is required if you speck out your machining tolerance and plating tolerance to a combined amount that you can live with.

Plate the easiest part to plate. This costs a little more, but is fantastic for your stated needs. It's hard, corrosion resistant and is naturally slippery.

James Watts
- Navarre, Florida
2000