Small Jet boats on Bigger Rivers - How much HP?

4pointswest · #1 10-22-2018, 01:05 PM

Howdy folks,

I'm thinking about buying a small jet boat for hunting/fishing and looking for some advice on HP requirements... Wondering specifically whether a 25hp jet on the back of a 15 or 16 ft john boat will provide enough jump to push 2 guys, gear and say an elk or a moose up-river (Bow River as an example)?

There's a few set ups like this on kijiji but 25hp seems like not much power under loaded circumstances. Working on a budget but also want to make sure i get something thats functional and has enough power to get going if need back.

What are you guys running? Anything else to think about?

Jamie Black R/T · #2 10-22-2018, 01:14 PM

I have an explorer industries 142 with a 40/30 4 stroke jet outboard on it and I would consider this the minimum for what you are after. (its for sale if interested)

Two guys and a bunch of gear and she gets on step and will cruise at around 26mph down and 22mph up. Add 4 moose quarters its a bit of a dog out of the hole but still doable.

SD1797 · #3 10-22-2018, 01:18 PM

I've been in a 60/40 jet on a 16ft Jon and loaded for a wknd of hunting and camping you could use more.

Jayhad · #4 10-22-2018, 01:21 PM

Get the most HP the transom will hold.

Problems happen in white water, and that's where HP will save you.

Flight01 · #5 10-22-2018, 01:28 PM

I have a 14.5 foot with 25hp merc 4 stroke. It’s a good fishing set up for a couple guys and gear. But would not be able to take much extra. Can go up some small creeks and is super light for manhandling if it were to get stuck on a sandbar.
By your description I’d go with an explorer 16 foot and 60/40 jet as a minimum

Sneeze · #6 10-22-2018, 07:54 PM

No experience with the jet.

I can speak to smaller boats with smaller engines. Your problem may not be fighting the current. The problem is getting the boat planing.

25hp prop engine wouldn't get you on-step with the use you have specified. So the jet wouldn't either with the power loss through the jet leg it would be even worse.

I agree with other posters and get the biggest engine your boat can handle.

A moose is a very large animal.

liar · #7 10-22-2018, 07:55 PM

Quote:

Originally Posted by Jayhad

Get the most HP the transom will hold.

Problems happen in white water, and that's where HP will save you.

yup

Talking moose · #8 10-22-2018, 09:11 PM

25 jet in a 16 footer ain’t even close for 2 men, gear, food, and a moose.

Talking moose · #9 10-22-2018, 09:13 PM

Quote:

Originally Posted by Jamie Black R/T

I have an explorer industries 142 with a 40/30 4 stroke jet outboard on it and I would consider this the minimum for what you are after. (its for sale if interested)

Two guys and a bunch of gear and she gets on step and will cruise at around 26mph down and 22mph up. Add 4 moose quarters its a bit of a dog out of the hole but still doable.

Any pics?

silver · #10 10-23-2018, 08:10 AM

I have a Lund Alaskan 16' with a 90/65 merc and I do not consider it to be overpowered. It will get three people up on plane, two and a moose, probably. I would not want to go any smaller. If I make a mistake and suck some sand in, there is a noticeable difference in power. Then I take the pump apart and re-shim the pump and I am good to go again.

Big Grey Wolf · #11 10-23-2018, 08:22 AM

My understanding is jets loose a significant amount of horse power relative to a prop driven boat, some where approaching 50% loss. Need to take that into consideration on your choice of minimum motor. Also jets plug up with rocks and other junk.

Tannerdog · #12 10-23-2018, 08:02 PM

I had exactly what you describe. 15' Tracker Jon boat with 25HP 2 stroke. Worked ok for 1 or 2 guys fishing but barely. No way you would plane with a moose or a bunch of gear. Very light and easy to move around as mentioned above but very under powered for a Jet. You lose 30% of your HP rating with a jet leg and the newer 4 strokes weight a lot more than the 2 stroke I used.

urban rednek · #13 10-23-2018, 08:44 PM

Quote:

Originally Posted by silver

I have a Lund Alaskan 16' with a 90/65 merc and I do not consider it to be overpowered. It will get three people up on plane, two and a moose, probably. I would not want to go any smaller. If I make a mistake and suck some sand in, there is a noticeable difference in power. Then I take the pump apart and re-shim the pump and I am good to go again.

I have to ask: how big are your friends?

OT- in regards to how much HP is required for a river jetboat: It is better to have it, and not need it, than to need it, and not have it.

silver · #14 10-24-2018, 07:00 AM

Quote:

Originally Posted by urban rednek

I have to ask: how big are your friends?

OT- in regards to how much HP is required for a river jetboat: It is better to have it, and not need it, than to need it, and not have it.

My friend is a tall skinny farm boy of about 175 lbs. His girlfriend I would say a bit more. Just how much more I don't know and I'm not asking. And I weigh about 240.

Two and a moose is possible but it could be close. Getting up on plane could take a bit. There are times it would be nice to have more power.

Justfishin73 · #15 10-24-2018, 07:18 AM

More than anything, what's boat rated for weight? Getting up to plane is irrelevant if you're sinking......

SKSniper · #16 10-24-2018, 07:27 AM

I have a Tracker 1542 with a 40/30 on a beefed up transom and i would not go any smaller. That extra power comes in handy when you hit the shallow stuff and need to move quickly. I can do a little over 40km down and around 35 upstream with gear, but once you had a second guy and some quarters/hunting gear you would be doggin it. I would say get a 35/25 at the very least. A 25 with the jet leg installed would only be pushing about 18hp and you will be disappointed.

4pointswest · #17 10-24-2018, 01:23 PM

Thanks for the info gents - much appreciated!

Dean2 · #18 10-24-2018, 02:20 PM

Out boards do not go up in price much as you move from 30 horse to 60 horse and stay not much higher till you break over 90. Since the prices are pretty close, buy the 75 or 90, jet that and not have to worry. Merc 75 horse vs 90 has less than an $800 price difference.

EZM · #19 10-24-2018, 08:53 PM

Maybe I'm mistaken in my interpretation when I read "600 lbs capacity including motor, fuel, passengers and contents" on the coast guard placard means that a 14' jon would be grossly overloaded with a motor, fuel tank, 2 guys, gear and moose.

Flight01 · #20 10-24-2018, 09:56 PM

My 14 foot is 1047lb max. Dry weight of engine is 187lb
860 left over for me and gas and gear and buddy and or meat,,,
But with the 25jet I would not be able to plane out near max. A 25 prop yes but not jet. 3 jerry cans of gas and 2 guys equipped with food water and gear to fish for a day is fine. Maybe time to do a weight test next summer. Add 5 gallon Pails of water till I find my max planning weight and safe handling weight.
Just bought a new wear ring and purchased a tiny tach so I can fine tune rpm, trim and intake height...
Was getting 35km/hr upstream and 40 down. Needs 18” of water at a distance of 40’ to get planning when loaded. Runs comfortably in 8” of rocky water with no pucker factor. 4” or less in the sandy rivers . Hydroplaning nicley on 2” sand bars this summer ... cool feeling when you drop back down into the channel

Really it is a make believe jet boat but works for me. Lots of fun on a budget

For those of you familiar with the Fort Mac area I went up past three forks and a couple hundred yards up the high hill before I ran out of water this summer