17 foot allweld with 60 hp Yamaha to slow

[Bass Cat]

I had a yamaha 40 hp 4 stroke 2008 and just traded for a new 14 60 hp four stroke. I am running the same speed with the 60 that I was running with the 40. After half throttle the 60 horse gains no more speed. Any help would be greatly appreciated.

[DennisG01]

Prop size? Trimming up? What's the bottom condition of the boat... fouled?

[Bass Cat]

The boat is aluminum and is in great shape. The motor is power tilt and trim and I tried it several different ways. The only thing I see on the prop is 13 G.

[DennisG01]

Is it the same prop as was on your 40?

[Bass Cat]

I don't know. I bought both new and never really checked the 40

[99yam40]

a lot more info is needed for us to make any guess at what your problem is.
Prop size, RPM, GPS speed, how it is mounted, etc

here is a site to look at what size prop and RPMs and speed they got on a rig like yours Performance Bulletins | Yamaha Outboards

[DennisG01]

OK, well, like mentioned above you're going to have to provide more info. I was hoping for the quick answer of "it's the same prop", which would explain the problem. If it's the same pitch (but new) as the old one, same thing. Try to find something in your old paperwork on your 40's prop. Or contact the dealer that you traded it to. You should also be contacting the dealer about this issue. This is good info to know and it would be good to write this down in your maintenance log... Also start one of those if you don't have it.

[rodbolt17]

and this is why Yamaha does not allow the sale of loose box engines.
its also why Yamaha sends a serialized PDI sheet with each motor.
on the PDI sheet is a checklist that BOTH the dealership rrep and the customer sign.
the tech that performed the PDI also signs.
on the PDI is a box for prop make and size.
there is a box for max RPM at WOT.
look at your copy of that PDI for what RPM it turned and what prop is on it.

four strokes don't tolerate overpropping.