Setting up and outboard jet

[Todd j]

I have a 50hp Merc with a jet pump on a 14' Valco flatbottom boat. I think the transome as it is makes the jet nozzle to high. As I cruise almost all of the thrust is above the waterline. I am hoping that If it is not set up properly I will be able to fix it and get another MPH or two out of it. I average 14MPH upstream with 2 people, dog, and decoy bag.

I would like to know how far above/below the bottom of the boat the jet intake should be?

Todd

 

[Lone Duck]

Re: Setting up and outboard jet

The jet foot should hang no lower than 1" below bottom of hull, angle of transom should be 15 degrees. Make sure nothing is in front of the jet foot on the hull bottom for at least 4' forward of it. Google outlaw marine jets and you will find all the info you need . Have fun!

 

[Todd j]

Re: Setting up and outboard jet

I read the info available at the site listed. It doesnt answer any of my questions in my post. I am not building a boat. I am trying to dial it in. I cant change the angle of the transome. All I can do is lower or raise the motor on it. It does not have a tunnel.

What I need to know is how far into the water the intake should be. Lone duck says no more than one inch. I can make that happen if necessary. Only tidbit I need is, Which part of the intake no more than 1 inch? Should the water stream off the bottom of the boat hit the intake at its center? Seems I dont want the front of the intake one inch below the bottom of the boat. How much of the nozzle should be above the waterline?? As it is now it looks like all the thrust is shooting above the waterline into the air. Seems that if more of the jetstream was pushing against water it would have more thrust?

Todd

 

[Lone Duck]

Re: Setting up and outboard jet

I read the info available at the site listed. It doesnt answer any of my questions in my post. I am not building a boat. I am trying to dial it in. I cant change the angle of the transome. All I can do is lower or raise the motor on it. It does not have a tunnel.

What I need to know is how far into the water the intake should be. Lone duck says no more than one inch. I can make that happen if necessary. Only tidbit I need is, Which part of the intake no more than 1 inch? Should the water stream off the bottom of the boat hit the intake at its center? Seems I dont want the front of the intake one inch below the bottom of the boat. How much of the nozzle should be above the waterline?? As it is now it looks like all the thrust is shooting above the waterline into the air. Seems that if more of the jetstream was pushing against water it would have more thrust?

Todd

OK. the heal of the foot should not be more than 1" below bottom of hull The top of the foot should be level with bottom of transum. That is why you need that 15 degree angle. You can get away with 1 1/2 " but then you are starting to get drag. It does not matter if the jet stream is above the water. To better explain goggle enhancing outboard jet performance by Chris Gorsuch. I apologise For giving you the wrong address earlier.

 

[Todd j]

Re: Setting up and outboard jet

Thats a good read! Thank you!

Todd