Pontoon Boat & Deck Boat Forum

I bought a 2018 Lowe ss250 with a 2019 Merc 150. It came with a 12 pitch aluminum prop. Around 20mph or 3800 rpm my rpms would go up and my speed would slow down. Almost like the prop wasn't getting any water.
So the dealer sent me a 13 pitch prop and stated this would solve the problem. Well..... that didn't work. Now they say I need a cupped prop. They're sending me a 12 pitch merc cupped prop and promised me this would solve the issue.
I'm not new to boating. This is my 3rd boat, and my 2nd pontion. The dealer stated they would come and pick the boat up and water test it again if I still wasn't happy with the results.
I would like to believe that this isn't the first boat of my make, model and engine that they have sold. So why are they having such a hard time with this? Any input would be greatly appreciated.

I'm far from a expert on props but I'm a thinking they are off base on their suggestions. A 12 or 13 pitch prop usually does fine on a 90 hp or thereabouts. With your 150 I'm thinking that a 15 pitch would be a satisfying start or maybe even the right prop for your boat. See if they will also throw a 15 your way also and give it a spin.

Junior wrote: ↑

Sun May 12, 2019 5:35 pm

Around 20mph or 3800 rpm my rpms would go up and my speed would slow down.

First it sounds like you have a GREAT dealer.

Given your description, it sounds like you might be experiencing a prop "blow out" if your speed drops and RPM's go up. A cupped prop may help and if not, they/you may want to drop your engine down one hole.

Have you played with your trim when this happens? Maybe you were trimmed up too high? Curious to know what the motor does when you trim down.

I was trying to find that sweet spot where the boat planted out and kept accelerating but that didn't happen. I trimmed up and down at all speeds and still had the same result.

The boat is in the water about an hour from my home. Unfortunately I can't get to it until the weekend to mess with it. I'll change the prop this weekend and look to see where they mounted the engine. Maybe they need to drop it down if possible. I guess I'll know more this weekend.

The dealer is 1.5 hours away from the boat so I'll have them just pick it up on Saturday if this doesn't fix the problem.

absolutely not enough prop, 14 or 15 pitch with a 150. That 13 prop will never bite enough with the power of a 150

I am thinking you may need larger diameter and more pitch with a 150.
Also, finding the "sweet" spot on a pontoon is difficult. Been boating for over 50 years and this is my first pontoon. Tritoon actually. I can play with my trim all I want and it makes little difference in speed or rpms. Does move the bow slightly but nothing noticeable about the speed.

riplipper wrote: ↑

Tue May 14, 2019 8:12 am

I am thinking you may need larger diameter and more pitch with a 150.
Also, finding the "sweet" spot on a pontoon is difficult. Been boating for over 50 years and this is my first pontoon. Tritoon actually. I can play with my trim all I want and it makes little difference in speed or rpms. Does move the bow slightly but nothing noticeable about the speed.

Pretty much same history here, my Tri came with 14.75 (pitch) x 15 dia. reliance prop on the Yamaha 150. I raised the engine one notch, which did improve top end and WOT a little, however at the same time in rough water, a following sea, or 2 or more people on the bow the prop will tend to blow out. Now I bought a 14 pitch 15 dia. Stainless Mercury Enertia prop which has a much larger rake and is overall larger than the Yamaha, it will hold the boat in almost any situation. I truly think the 14 pitch enertia is the perfect prop for tritoons with the 150 - 200 horse

I agree. 14 or 15 pitch enertia, depending on weight of tritoon.

Here's a thread from last year about my experience with a prop on my 150. As others have said, it seems like a 15 pitch is the way to go.

http://pontoonforums.com/viewtopic.php?f=2&t=25641

I this thing of any use?

https://www.mercurymarine.com/en/us/pro ... !/step-one

boocat wrote: ↑

Mon May 20, 2019 6:22 am

I this thing of any use?

https://www.mercurymarine.com/en/us/pro ... !/step-one

in a word... NO. you should contact a mercury prop dealer, or Ken at Prop Gods in Ft. Lauderdale. you probably need the 14 pitch enertia prop, I almost guarantee your problems will be solved possibly raising one hole can also help gain speed and rpm. what hole from the top is your engine on now.

My 2014 Verado 150 spins an Enertia 14p. High 30's. Good handling.

zoom650 wrote: ↑

Tue May 21, 2019 8:42 am

My 2014 Verado 150 spins an Enertia 14p. High 30's. Good handling.

Exactly, I think the 14P Enertia is the perfect prop for the 22-24 ft tritoons with a 150. pricey prop, but it's ultimately worth it if you are really looking for top performance

Junior, I'm a little late to the party, but the fix for your issue should be a new Propellor bore sleeve. Some people call it a blow out ring. It a white plastic ring that snaps into the lower unit right in front of the prop.

https://www.crowleymarine.com/parts/759949.cfm