Should I be happy with size and speed?

[jlwardn]

I recently bought a old party barge 24DL. It has a 50hp Mercury 2 stroke engine and not much in seating. Normally it is me,wife, son and dog on the boat. Boat tops out at 20mph but chugs the fuel. Cruises easy at 11/12 mph and still eats the fuel fast. I like the feel of 18-20mph but don't want to run WOT all the time.
I had a few friends over and ended up with 10 people on the boat(4 were kids)..........engine seemed way under powered. I hope to never have that many on the boat again but would not like to drag along if I do. I also would love to be able to tow a tube or skier behind. I don't think I could do that now. Any suggestions, help or advice.....or should I just suck it up and live with it?
I would consider putting on a bigger(up to 90hp) used motor if could find a deal and make mine go away in the process.

[r&s20]

its not uncommon for a 90 hp to run 22-27 mph. but even with that a old 2 stroke will still burn alot of fuel.
a 90hp is what i'm running and we cruise at 15-18mph and we enjoy it.
as for tube pulling even with a 90 it will be good for young ones,not so much for older ones

[DWRAT]

If you're getting 20 mph out of a 50 hp motor on a 20+ foot pontoon you are doing VERY WELL....
If you want to save fuel you need a bigger motor that doesn't have to work so hard.

[MH Hawker]

i dont mean to sound rude but all boat motors suck gas like its going out of style, a 2 stoke uses more than a 4 stroke, your not going to get much if any speed out of unless its badly proped, so it is what it is, open a beer and enjoy the ride

[jlwardn]

The fuel economy is important but not a priority since I realize I can buy a lot of fuel for what a newer bigger motor would cost. I would love to be able to run 16-18 mph and not have it WOT. I use 6 gallons in about 2 hours with my 50 hp at about 14mph going up river with slow current. Already planned on getting bigger fuel tank.


My son is only 5 years old so I don't need to pull people fast. I would like to see if I can still ski or wakeboard at my age.
If a 90HP could run 16-18mph and only at 50% throttle I probably would be getting better fuel economy than I am now at close to WOT on my 50hp motor. I also would love to be able to go 24-27mph at times or at the very least be able to pull wife and kid around on tube. Where everyone goes to relax and tube is about an hour away when only going 14/15mph. Would love to be able to cut that time as well.

[Jake_Daddy]

We had an old 24' party barge with an old merc 90HP on it and could get it to 24mph at WOT and nice conditions and a light load while sucking down the gas. Speed wise your gonna do better than the 50hp at half throttle but I dont imagine you hitting 18mph there. If I remember right ours had a 12P prop on it and we would start a "fast cruise" around 4000rpm probably going in the 17-18mph just when it would stop plowing through the water and you get a slight bit of lift on the toons. Still not great on the gas but a heck of alot better than at WOT.

[r&s20]

Jake_Daddy is right. the numbers he gave is almost identical to mine except i'm running a 13p prop

[ROLAND]

I think if you're getting 20 mph out of an older 50 hp 2 stroke you should be happy... i've got a 75 horse 4 stroke and when the boat was brand new and the water was smooth like glass, I could get 24-25 mph... probably around 22-23 now ( 6 years later )....

[jlwardn]

I am happy at the 20mph out of a 50hp hp engine. In order to hit 20mph I have to run WOT which is what I really don't want to be doing to the motor. In a perfect world I would run 16mph and be at 50% throttle and if I wanted to drive WOT....hit 24mph.
If I can find a deal on a 90hp I would take it.....otherwise I'll live with what I got until upgrade time.