Renkou1
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- May 18, 2010
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One of my pet projects has been trying to find out how to tell a factory A65 from a factory A75...data plate not withstanding/ missing. There have been several threads about how to convert. I'm looking for information on which serial numbers go with which engines. Does anyone have a source. The TCDS do not...as far as I can tell designate which series is which serial number range. My overhaul / parts manual does not.
One interesting bit in the parts manual specifies different internal parts for the A75....not just those mentioned in the conversion threads. The smaller cylinder hold down studs --the top and bottom one on each cylinder are shorter overall on the A 75 than the A65 studs; part numbers 25329 vs 402127. The crankcase thru bolts at the rear of the front main bearing are replaced with 25239 studs in the A75. Exhaust valve called for A75 is 21479. Carb section only lists Stromberg NA carb for A75. Cam listed is 4546 for A75 but is alternate for A 65. I leave out the often discussed parts for conversion as I am trying to find a source for determining Factory serial number ranges.... or failing that a way to tell by looking at the exterior whether the case left the factory as a 65 or 75. Facts and guesses apprieciated. R
One interesting bit in the parts manual specifies different internal parts for the A75....not just those mentioned in the conversion threads. The smaller cylinder hold down studs --the top and bottom one on each cylinder are shorter overall on the A 75 than the A65 studs; part numbers 25329 vs 402127. The crankcase thru bolts at the rear of the front main bearing are replaced with 25239 studs in the A75. Exhaust valve called for A75 is 21479. Carb section only lists Stromberg NA carb for A75. Cam listed is 4546 for A75 but is alternate for A 65. I leave out the often discussed parts for conversion as I am trying to find a source for determining Factory serial number ranges.... or failing that a way to tell by looking at the exterior whether the case left the factory as a 65 or 75. Facts and guesses apprieciated. R
