A
Aussie Ed
Guest
"Have just purchased a boat wi
"Have just purchased a boat with a 1983 40 HP Yamaha with the intention of upgrading to new higher horsepower motor but the 40 is in great condition. I've checked the manual and all the specs are identical to the 50 HP model with the exception of the main jets and the spark plugs. Is this all that will need to be changed to get another 10hp out of the 40? Is the CDI unit different? (Timing, bore, stroke, piston size etc. is all identical)"
"Have just purchased a boat with a 1983 40 HP Yamaha with the intention of upgrading to new higher horsepower motor but the 40 is in great condition. I've checked the manual and all the specs are identical to the 50 HP model with the exception of the main jets and the spark plugs. Is this all that will need to be changed to get another 10hp out of the 40? Is the CDI unit different? (Timing, bore, stroke, piston size etc. is all identical)"