What size prop for 40hp Yamaha??

[Riverdog]

Hey guys...

I've recently purchased a 15' Hightide with a 40hp Yamaha. I took the boat out today, and it takes FOREVER to get on plane. I could go WOT, drink a beer and bait my hook before it even thought about planing out. Motor is running strong, just had it service two days ago. I'm thinking the prop may be the wrong size. The only markings on it say "15 G". It's a stainless prop. Motor also sounds like it lugging, and not turning enough rpms.

What do you guys think?

[BigBallin]

Can you raise the motor up a notch? I know you also had some "weight" in the front of the boat, did you try it without him in it? The prop is prolly a 15 pitch but without knowing the diameter me in the dark.

[saltynut]

If the motor is running strong as you stated it should not lug. If it is manual tilt/trim you should try different settings as well as moving your load around. A 15 pitch prop as long as it is not severely worn or damaged should be about right depending on diameter. I suggest you pm Nab or DVR for more expertise.

[Riverdog]

I just had another thought....

The guy I bought it from said that he had just put the jackplate on it.... I may need to raise it up some.....

Question #2: How far?

[BigBallin]

I usually start off with the flat horizontal plate above the prop(cant remember what its called) level or even a tad bit above the lowest spot on the hull and take tools and run it. You'll have to adjust it a little up or down and try it with and without a load to figure out the sweetest spot for what you're lookin for. Remember when you're settin it up this things gonna spend a lot of time with 2 guys, a dog or two, a blind, and a sac of dekes in it. Also, when you're messin with the engine always make sure you got a good pee stream coming off the motor. Depending om the weather we may be able to go tomorrow and play with it, if it looks good I'll give you a hollar.

[Nab]

A 14p or 15p should be fine depending on the diameter - sounds like the setup needs some tweaking - the only 16p prop that the 40 will turn is the Mercury some people run.

[smitty]

long shank or short shank

[Riverdog]

yep, it's got a shank....

what should I measure and what would a short/long shank be?