2005 Yamaha F90TR 90HP Outboards Factory Service Manual, Page 99Get this manual
Power unit 3Compress the valve spring, and then install the valve cotters using thin screwdriver with small amount of grease applied to it
Installing the valves
1Install new valve seal onto the valve guideE
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2Install the valve 2, valve spring seat 3, valve spring 4, and valve spring retainer in the sequence shown, and then attach the special service tools
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