Pontoon Boat & Deck Boat Forum

I purchased my pontoon used. The previous owner installed a 150 Yamaha on the boat. The Yamaha is a 25" shaft. My understanding is most pontoons need a 20". When ever I give the motor almost full throttle I notice a large amount of water being kicked up around the cowling of the motor. Think of it as a wall of water on both sides of the motor. I am thinking this is because the motor is sitting to low. The motor also looks like it is bolted as high as it can be. Please take a look at the picture of how the motor is sitting and confirm or deny that the motor is sitting to low. If it is sitting to low would the easy fix be buying a manual jack plate and setting it to the correct height?

That looks way to low to me. If your transom pod slopes down a lot it might not be too bad but if its fairly flat at the bottom you are way to low. Here is a video of mine when it was low, I raised it up as high as I could and it helped out quite a bit. I would have gone another thole or two higher if I had them.

https://www.youtube.com/watch?v=AdmBOUXzroM

Here is how mine sits. Don't know if that helps. But it seems fine on mine. I don't remember looking back at it a WOT though. Net time I get out I will and see how much I get.

here are some more pictures of how the motor currently sits. I am guessing it is about 4" to low.

[img]http://i.imgur.com/v2O6wXRl.jpg[/img]
[img]http://i.imgur.com/VtptatFl.jpg[/img]
[img]http://i.imgur.com/vQhtgwil.jpg[/img]


Edit: am I adding these pictures incorrectly?

You'll have to upload them direct as the 3rd party hosting doesn't seem to work on this forum. It needs some work but the owner is kinda busy with work is what I read.

You'll also want to resize them to 800x600 or close to that or they will end up huge.

[quote="JLester273"]You'll have to upload them direct as the 3rd party hosting doesn't seem to work on this forum. It needs some work but the owner is kinda busy with work is what I read.

You'll also want to resize them to 800x600 or close to that or they will end up huge.[/quote]

Good to know. Here is the pictures.

[quote="cody0707"]I purchased my pontoon used. The previous owner installed a 150 Yamaha on the boat. The Yamaha is a 25" shaft. My understanding is most pontoons need a 20". When ever I give the motor almost full throttle I notice a large amount of water being kicked up around the cowling of the motor. Think of it as a wall of water on both sides of the motor. I am thinking this is because the motor is sitting to low. The motor also looks like it is bolted as high as it can be. Please take a look at the picture of how the motor is sitting and confirm or deny that the motor is sitting to low. If it is sitting to low would the easy fix be buying a manual jack plate and setting it to the correct height?[/quote]


How long have you owned the boat? Looks like the PO just slapped that 25" motor on there for a sale. That is most definitely wrong and won't work in it's current configuration. You could add a manual jack plate to get the motor up, or change the motor over to a 20" shaft, the jack plate would probably be easier and cheaper. how thick is your transom? the one picture looks like it is one 1/4" plate of aluminum?

[quote="FLOUNDERPOUNDER225"][quote="cody0707"]I purchased my pontoon used. The previous owner installed a 150 Yamaha on the boat. The Yamaha is a 25" shaft. My understanding is most pontoons need a 20". When ever I give the motor almost full throttle I notice a large amount of water being kicked up around the cowling of the motor. Think of it as a wall of water on both sides of the motor. I am thinking this is because the motor is sitting to low. The motor also looks like it is bolted as high as it can be. Please take a look at the picture of how the motor is sitting and confirm or deny that the motor is sitting to low. If it is sitting to low would the easy fix be buying a manual jack plate and setting it to the correct height?[/quote]


How long have you owned the boat? Looks like the PO just slapped that 25" motor on there for a sale. That is most definitely wrong and won't work in it's current configuration. You could add a manual jack plate to get the motor up, or change the motor over to a 20" shaft, the jack plate would probably be easier and cheaper. how thick is your transom? the one picture looks like it is one 1/4" plate of aluminum?[/quote]

Yes. The PO told me it was a motor he had on a different boat. I have a manual jack plate sitting at home that has only a 4" setback so hopefully it wont stress the transom to much. The jack plate should be able to raise the motor until the cavitation plate is closer to the bottom of the motor mount. I am not sure how thick the transom is off hand but the PO said the motor has been mounted on the boat for about 15 years and I haven't noticed any issues or cracks in the transom.

I would first see how fast the engine will run in a straight line. I'd think you'd be happy to get 5500 to 5800 rpms. That tells you if you're propped right.

Then how does your boat handle in tight turns. If the propeller ventilates, chances are your lower unit is too high.

They always say you should be able to look down and see the anticavitation plate when running at a fast cruise. That's not always the case with pontoons because each brand and engine configuration is different. My tritoon is setup perfectly, and all I see is spray over the lower unit.

Your engine pod looks like it's well built and a 4" jackplate would probably work. But you might want to adjust your engine up and down first before adding it.

Is the boat even rated for 150 hp? Few boats of that vintage were.

[quote="Bamaman"]I would first see how fast the engine will run in a straight line. I'd think you'd be happy to get 5500 to 5800 rpms. That tells you if you're propped right.

Then how does your boat handle in tight turns. If the propeller ventilates, chances are your lower unit is too high.

They always say you should be able to look down and see the anticavitation plate when running at a fast cruise. That's not always the case with pontoons because each brand and engine configuration is different. My tritoon is setup perfectly, and all I see is spray over the lower unit.

Your engine pod looks like it's well built and a 4" jackplate would probably work. But you might want to adjust your engine up and down first before adding it.

Is the boat even rated for 150 hp? Few boats of that vintage were.[/quote]

The boat is rated for a 120. It does well in tight turns. The motor will push the boat 28 mph the way it is currently set up. I had a buddy ride by me in another boat and he said it looks like the motor is pushing a lot of water. While running close to full throttle all I see is a bunch of water coming up around the engine cowl. I don't have a picture or video of my boat doing this but here is a video of another pontoon that does what I am describing although it seems worse to me on my boat.

https://youtu.be/_IRXrK0IN-0

Figured I would update this post as I am still trying to get this all figured out. I ended up adding a manual jack plate. I think I raised the motor up just a touch to high as the prop seems to ventilate and I can’t really raise the bow up high enough to reduce the plowing.

Here is a video of my boat with a full tank of gas (26 gallons) and just me. At wide open throttle I was only getting 4800 RPM from the motor. The rpm range is listed as 4500~5500. At 4800 I was able to get 33.7 mph.

As you can see in this video my motor pod puts out a ton of spray. Is there any easy or practical way to fix the motor pod from riding in the water and kicking out that much spray?

https://youtu.be/FbjA0T89yl4

33 mph is impressive for a pontoon without lifting strakes.

Thanks for sharing that video. There is no way his boat was rated for 200hp, I love it!

Since your boat never really gets on plane, is it possible that its throwing all that water because the boat is never getting on plane?

As far as motor height, the cavatation plate should be level with the bottom of the pontoons.

I was looking at other pontoon boat setups. The Bently 240 Cruise is setup like my boat and allows for a 150hp motor. I looked closely at the motor pod and noticed the fins on the side of the pod are forcing water down. A picture of my setup shows the fins are bent out of place. I plan to bend the fins back and hope the metal isn’t weekend and won’t need to be braced to prevent it from bending back up.

Here is a picture of the fin. Also you can see my jack plate to get the longer shaft motor higher up.

Looks like something hit the fin, weird. Its worth a try but not sure if it will make a difference.

I didn't previously say it but that boat in the initial posting looks like it has 19 inch diameter toons.

Putting 150 no on a 2 toon boat is a waste of horsepower if the boat doesn't have 25 inch toons and lifting strakes. No matter what you do, the bulls will be plowing through the water.

Motor pods can be made for 20 inch motors or 25 inch motors. My Bennington and most late model boats are 25 inch motored.

The reality is that 33 mph is about all that boat has in it.