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  for Metal Finishing since 1989
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Nikasil coatings

I recently damaged a piston and cylinder when my carburetor leaned out. The piston isn't the question as I will simply replace it. The question is that some of the piston melted away on to the cylinder walls and left a deposit on the cylinder. If I can save the original cylinder by honing it out to within specs, will this disturb the Nikasil finish and leave the cylinder unprotected? If this is the case is there any from of application that can be preformed at home that in a small shop that will return the cylinder to a somewhat protected state? Or will I render the cylinder useless be honing it clean again? If there is product that I can apply myself could you please direct me to a source?

Thank You Sincerely,

Kevin McGrath
- Leamington,ON. CA
2002

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You can remove the piston residue with straight Muriatic Acid. Most of the time when someone experience's a stick it usually ends up marring the bore. Get yourself a Bend a Lite from Travers and start reading the piston if not already. A Nikasil cylinder can be lightly honed with a Ball Hone 10% less then bore. 240 Grit Alum/Oxide works best to place a "Plateau" finish per Brush Research procedure. Another note. Clean the Acid out well with a Detergent cleaner 2 or 3 times. This also applies to the after hone cleaning. Use a paper towel to read if any residue is present. Chamfer the rings and set the gap at specs, dress the piston skirt to a nice smooth radius it will help keep the film layer on the wall. The top .080 of the bore takes the most abuse check it carefully any imperfections there will have large impact on power.

Jim Shoulders
- Dense, GA, US
2002