An oversize rebuild kit for the Kohler 77mm, 624cc twin-cylinder engines whose cylinders have been bored .010 over, to 77.25mm. The kit contains two 77.25mm pistons with matched rings, the complete gasket set (head, valve cover, intake and exhaust gaskets and small O-rings), two crankshaft oil seals and crankcase sealer. Rods, valves and bearings are not included. On a standard 77mm bore these pistons will not fit, so measure first. It fits the CH18, CH20, CH22, CH620, CH621, CH640, CH641, CV18, CV20, CV22, CV620 and CV640 once bored; some CH22, CH620 and CH640 engines are the 80mm version, so check the displacement on the nameplate. Before assembly, check the piston-to-bore clearance, ring end gap and groove side clearance, and use a ring compressor. The standard-size Kohler piston for these engines is 24-874-46-S; these are its .010 oversize equivalent.
- OVERSIZE PISTONS, RINGS, GASKETS AND SEALS - Two 77.25mm (.010 oversize) pistons with matched rings, the complete gasket set, two crankshaft seals and crankcase sealer. Rods, valves and bearings are not included.
- FOR A CYLINDER BORED .010 OVER - The cylinders must already be machined to 77.25mm. On a standard 77mm bore these pistons will not go in; measure the bore or check the machine shop's records first.
- FITS KOHLER 77MM, 624CC TWINS BORED .010 - CH18, CH20, CH22, CH620, CH621, CH640, CH641, CV18, CV20, CV22, CV620 and CV640. Some CH22, CH620 and CH640 engines are the 80mm version, so check the displacement on the nameplate.
- WHEN AN OVERSIZE KIT IS RIGHT - When the bores are worn or scored past their limits and have been bored to the next size, or a previous rebuild left them at .010 over.
- MEASURE BEFORE IT GOES TOGETHER - Check the finished bore against the piston for the specified clearance, check ring end gap and groove side clearance, and use a ring compressor.