Watkins 27 - Help with Prop

[MoonDoggy]

Hello to All,
New to the net and love all the go info here. Just bought boat and was going thru the paper work. The boat seems to be way over prop'd which explains only getting about 1500 rpms out of the YSM8. According to the service manual, I should have a 12" x 7-1/2" not a 13" x 12". I believe the bore is 7/8". Can anyone confirm or give some insight on what they are using.

Thanks Moondoggy!!!

[billangiep]

Moon,
I owned a Watkins 27 Pilot House with Yanmar 2GM 15hp with a 3 blade 13" X 11" and it was over propped 2500 rpm. max. The fuel consumption was just over a cup per. hr. though. So I'd say yes you are way,way over propped. My son has an Irwin 25 wide body with an YSM8 and he swings a 12"X 8". I'd guess the 12"X 7 1/2" is pretty close to what may work for you.
Bill,