first run in the jet

[JoshKeller]

1986 fisher marsh hawk 2v 1648, 1994 johnson 50/35 jet. 2 people (450 lbs approx), fishing gear, two batteries, bow mount trolling motor, 5 gallon of gas.

jumps on plane with passenger sitting in front, runs approx 22 mph. A bit slower with passenger at the back, but certainly acceptable, but runs on plane down to 14 mph, top speed of 23 - 24 (gps was bouncing between).

the bottom of the boat is heavily dented, but doesnt leak. im thinking this is costing me a few mph. no spray from the jet, ran great in small waves, and turns on a dime due too the hard chines welded on over the two outer most chines. does this all seem about right?

we had no problem running in 8 inches of water on plane, but since the water is up, i couldnt find anything shallower to test.

 

[PATRIOT]

Thanks for the test results . . . I'm only replying because the 22mph caught my eye as my 87 Lowe Superior 14V was clocked at that very speed (22mph) over a measured distance with just me and 6 gallons of fuel on a Nissan NS15B 2-stroke. Always wondered how much more HP I would have to have to haul 2-3 times the load.

 

[JoshKeller]

I have a 1648 alumacraft with 35 prop that's heavily decked out, two batteries, 24 v trolling motor that does 33-34 mph but is no where near as practical as the jet in the water I fish

 

[dhoganjr]

Sounds about right.

Have you checked the impeller wear for nicks, gouges, etc. Dressing or sharpening the impeller will help if it hasn't been done. Clearance between impeller and liner. If there is enough wear you can shim it down.

These things make the biggest difference in performance especially with lower hp jets. The hull is costing some mph, but harder to address. You can attempt to knock the ones you can get to out to straighten them a bit or use body filler or epoxy to fill in some of the worst ones. Or just run it like it is if you are not that concerned with it.

Mine is a fishing boat not a race boat, so the few extra mph on top end doesn't concern me that much.

Have fun with it, you'll find the shallow water soon enough. Try to keep the foot out of the rocks, that gets expensive.

 

[He Reigns]

My friend Lowe 16/52 flat bottom with a 40/25 run out at 22 mph going upstream and 25 mph going downstream. This was with 530 lbs of people, 2 batteries, tolling motor, fishing gear and 12 gallons gas. We checked it today on the GPS. Hope this helped......

 

[airbornemike]

For those of us that run smaller jets 25hp to 50hp, it seems most everyone is running around the same gps times. I run a 30/20hp and had thoughts of a 50/35, I put it out of my mind after considering the power to weight ratio and the size of the flows I'm on. I'm running rivers that are sometimes barely 50' in width and running these at 20mph is sketchy enough.

 

[BigTerp]

dhoganjr » Yesterday, 3:28 pm[/url]"]
Have you checked the impeller wear for nicks, gouges, etc. Dressing or sharpening the impeller will help if it hasn't been done. Clearance between impeller and liner. If there is enough wear you can shim it down.These things make the biggest difference in performance especially with lower hp jets. .

This is the ticket. Drop the foot, check the impeller for wear and sharpen (if needed). Also check the liner for wear and replace if needed.

 

[BigTerp]

airbornemike » 52 minutes ago[/url]"]For those of us that run smaller jets 25hp to 50hp, it seems most everyone is running around the same gps times. I run a 30/20hp and had thoughts of a 50/35, I put it out of my mind after considering the power to weight ratio and the size of the flows I'm on. I'm running rivers that are sometimes barely 50' in width and running these at 20mph is sketchy enough.

I agree with this as well. I couldn't imagine going 30+ through the nasties!! I GPS'd mine yesterday and topped out at 28mph, which is more than enough, especially when runny skinny. This is a '96 Tracker Sportsman 1648MV, 1994 Johnson 50/35 (same as Josh's) with 2 group 27 batteries, trolling motor, fishing gear, 2 people (aprox. 500lbs), 6 gallons of gas and cooler.

 

[Ranchero50]

I think the biggest trick with a jet is how slow you can go on plane. Jet boats steer with the nozzle. I love having the throttle backed off and being able to hammer it to dodge the nasties.

 

[JoshKeller]

Ranchero50 » Today, 12:25[/url]"]I think the biggest trick with a jet is how slow you can go on plane. Jet boats steer with the nozzle. I love having the throttle backed off and being able to hammer it to dodge the nasties.

it was definitely staying on plane at around half throttle. i was able to idle up to the riffles to get a clear idea of where to pass through, then drift back about 100 feet, hammer down, and be on full plane. we ran up the opequon about 3 miles.

 

[JoshKeller]

after running some more, ive determined that 22 mph is where this boat wants to run, no matter the load or conditions. motor is turning 5200 rpm. ran 17 miles last sunday and the motor ran perfect. ran from hancock to 15 mile creek. 17 miles, 4.5 gallons of gas.

stays on plane down to approx 15 mph.

just wondering why 22 is what she runs whether im alone, with two people, or any other load.