2004 merc 50 2 stroke, disappointed!!!

goombadi99

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Apr 11, 2010
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I have a 2004 bass tracker targa 16ft aluminum. Its has a mercury 50 two stroke. I just replaced the prop with the factory 10.5diam 13pitch. With the motor slightly trimmed I am only seeing about 23mph . Oh and by the way. The boat weighs about 1400 lbs. I am turning the engine at 5500rpms @wot. Do these numbers seem accurate to you guys? This is with me and one fishing partner, two tackle boxes and 5 fishing poles, no water in the live wells, and the windshield closed. This just seems a little on the slow side to me.
Thanks in advance.
 

4JawChuck

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Aug 7, 2009
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Re: 2004 merc 50 2 stroke, disappointed!!!

Yep sounds about right, what were you expecting?
 

goombadi99

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Re: 2004 merc 50 2 stroke, disappointed!!!

one good thing about this set -up is the fuel economy. went out for about an hour total @ wot for the whole day and my gas gauge never moved off of full
 

trendsetter240

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Re: 2004 merc 50 2 stroke, disappointed!!!

one good thing about this set -up is the fuel economy. went out for about an hour total @ wot for the whole day and my gas gauge never moved off of full

You would probably be able to squeeze another 4mph or so out of it by raising the motor and picking the best prop. Could be a lot of work and expense for little benefit though.

What's the max HP the boat is rated for?
 

goombadi99

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Re: 2004 merc 50 2 stroke, disappointed!!!

the motor is already at the highest setting, there is only 3 settings and its on the top one. The boat mx hp is rated for a 90. The other thing that i noticed with the boat @wot is that it almost seems like it isnt planed all the way. the nose still seems up higher than it should. I feel like i almost have to look up over the wind shield to see right infront or the boat, I hoipe this is making sense, because its not like the nose is traight up. I can feel the boat start to plane but it just does seem like the front is flat on the water @wot like if i was cruising at 5mph.
 

trendsetter240

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Re: 2004 merc 50 2 stroke, disappointed!!!

the motor is already at the highest setting, there is only 3 settings and its on the top one. The boat mx hp is rated for a 90. The other thing that i noticed with the boat @wot is that it almost seems like it isnt planed all the way. the nose still seems up higher than it should. I feel like i almost have to look up over the wind shield to see right infront or the boat, I hoipe this is making sense, because its not like the nose is traight up. I can feel the boat start to plane but it just does seem like the front is flat on the water @wot like if i was cruising at 5mph.

Are you talking about the tilt/trim on the motor or the actual mounting bolts? What I meant was by raising the motor vertically on the mounting bolts you can increase speed.

If you are using the tilt/trim which adjusts the angle of the motor then that might be the reason for the high bow. Also consider moving some heavy items forward in the boat to better distribute the weight.
 

goombadi99

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Re: 2004 merc 50 2 stroke, disappointed!!!

i was refering to the motor mounting positions, not my power trim.
 

Alumarine

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Feb 22, 2005
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3,738
Re: 2004 merc 50 2 stroke, disappointed!!!

Your power trim should be able to get the nose down for planing.

I can get 30 mph in my 16.5 but it only weighs 500 lbs plus stuff.
 

jeffdjpeat

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Mar 25, 2009
Messages
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Re: 2004 merc 50 2 stroke, disappointed!!!

1400Lb seems heavy for an alum fishing boat. I have a fiberglass bow-rider 16ft and it is not that heavy. Is you motor a long shaft or short shaft? have you adjust the trim/tilt while driving to see if the bow will drop, if the motor is equipped with power trim. just a shot in the dark.
 

goombadi99

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Re: 2004 merc 50 2 stroke, disappointed!!!

going by the tracker web site the 17ft targa weight is 1401 so i assumed i would be right about that, you have to remember this isnt a jon boat, it is equivilent to the lund lake boats, with decent gunnels, 92in beam deep v with dual console and walk through windshield.
I have tried playing with the trim while @wot and no results with it. if i trim too high the boat revs too high. The sweet spot is wot and then two bumps on the trim and it brings it from 5200rpm to 55-5600 rpm where it is at the max rpm for the engine. anything higher than that and the motor revs and the boat starts losing speed.
 

Silvertip

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Sep 22, 2003
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28,771
Re: 2004 merc 50 2 stroke, disappointed!!!

There is something wrong with your numbers. 5500 rpm on an engine with 1.83:1 gears and a 13P prop shows 37% slip which is terrible and accounts for the lack of speed. That boat with that load as you expect, should be in the 28 - 32 MPH range. So the next thing is what did you measure speed with. If it is GPS then we know speed is accurate. If not, then you are probably going faster than you think. Are you using trim correctly? Using the numbers you provided 13% slip (a more normal number) would yeild 32 MPH. Since the boat is also rated for a 90 HP motor, you are just a little over half of what the boat is rated for. A rule of thumb is that for acceptable performance a boat should be powered with no less than 70 - 75% of the maximum rating and your 50 amounts to only 55% of maximum hence the huge slip numbers.
 

goombadi99

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Re: 2004 merc 50 2 stroke, disappointed!!!

i am going by what the speedo says on the console. I dont have a gps to measure the speed with. When I bought the boat it had the same prop on there that i bought, but the original prop was banged up pretty bad with a crack in it, thats why i purchased a new prop. i called the local tracker dealer and he confirmed that the 10.5in 13 pitch prop was the approp one for the boat. he also said that the boat should only do about 26mph according to his knowledge of these style boats. I dont mind only doing the speed i am as long as it is the appropriate speed and perormance for the boat. I just thought coming from a 1985 17ft bayliner bass boat with a 85hp force engine that would push the 41mph that this boat should be in the upper 26-29mph range. maybe i am expecting too much from this little 50 horse?
 

4JawChuck

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Re: 2004 merc 50 2 stroke, disappointed!!!

Get the largest motor the boat was designed for, you won't be happy with it any other way...those boats are tanks.

For comparison my 16.5' Tuffy did 32 mph with a 50HP Yamaha and similar prop, the boat weighed 800 pds dry and close to 1200 pds loaded with fuel and one passenger. Your slip numbers are way up there because you are barely above planing speed and the engine is loaded heavily. With four passengers I was lucky to get 26 mph out of it and it rode nose high also.

Completely different boat with a 90Hp on it though, top speed with a single person was close to 50 mph....my mileage actually increased with the larger motor and pulling a skier was no problem. I can cruise at 40mph at half throttle and use half the fuel the old 50 used to use if you compare actual miles covered. Underpowering a boat is about the worst thing you can do, I see them all the time on the river with the nose way up in the air and crawling along at barely 25 mph with a little 50hp screaming away. It seems like it always a newer boat with a wide beam that some dealer sold as a cheapo package deal.

I don't know how people can stand it, it takes twice as long to get anywhere and the noise is intolerable.
 

goombadi99

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Apr 11, 2010
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Re: 2004 merc 50 2 stroke, disappointed!!!

well the nose of the boat isnt way up in the ait @wot, just not as low as i thought it should be. there is a noticable difference from take off to wot plane, but just seems like the boat should be lower in the front?
With the given info on rpm wot and speed, am i going to damage my boat? it runs great and rides really nice, and i dont wanna take anymore money out of my account just to repower the boat to gain 10mph. either
 

verado7

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Apr 28, 2009
Messages
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Re: 2004 merc 50 2 stroke, disappointed!!!

i hav eroughly the same setup as you boat size and weight but a i have a v-hull and those numbers look accurate .
 

verado7

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Apr 28, 2009
Messages
511
Re: 2004 merc 50 2 stroke, disappointed!!!

your doing okay then - but i like you would love some more speed but that requires more hp and more $ - realistically you would want a 75 - 90 hp for that boat or better yet is rated to 115hp ? up to 75 gets about same fuel economy/slight difference -above that theres a good difference so you need to decide how much fuel and oil you want to buy along with the hp .
 
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