I recently put a 1992 GDLT with a 16hp Vanguard on a 16' Scott Duckboat. Bottom width about 38" at the transom, boat is long and narrow. Tested it today with the GPS when we took the dog for retrieving practice. Motor starts and runs OK, no complaints. With 2 people and a dog my top speed is just under 10mph, which is OK for my needs, but wondering if that is what I should expect from that motor.

I would think you would be slightly better than that. Not much, but probably 11-12 depending on how much weight. What rpms are you turning, in water and out? How does the prop look?

With a 16 on a 1448, we were running right at 11 with three decent size guys and a hunting load. I want to say it ran around 15 with just my little brother and no gear.

Sorry don't have a tach on it (yet). Prop is original so I guess 9x6? Not too much wear.

Measure the prop. They can look fine even missing an entire inch.

Without a tach, its hard to tell you if you are getting all she's got.

I run a 9x6 on my 27 HP LT so I figure you should be running a smaller prop.

Thanks. I just measured the prop dIa and its around 7". Not sure I measured it precisely as I had to lean out from the dock with a tape measure. Any idea what the factory prop size was "originally"?

on my 13 hp lt the prop was a 8x4 I think you need a new prop

16GDLT comes with a 9x3, either way its time for a new one.

correct size wrenches definately help. first try to get it off, that will be the test if its going to be a big deal or not. if its been on there awhile without any antiseize put on it, more then likley its gonna be a big deal. good luck!!!

Got a new 16 hp gd on 14x36 with me and dog i get 17.3 mph by GPS I think thats pretty good will try it with load soon and let you know what speed i get and how much fun i had doing it .

Wow that's almost double what I'm getting. Duck season starts tomorrow so the prop change will have to wait until winter. Hope you get lots of use of your new GDLT this season!

I have a 23 gd longtail with a custom stainless exhaust on a 14x46 skiff and with just me 210 lbs i get a steady 18-19 and if i run it at the surface in shallow water i can bump 20-21.

2000 GDLT 16HP on a 1436 riveted john with Steel flex on the bottom. I get 15-16mph with just me in the boat (210lbs + battery) I hunted it last weekend and got 11mph with myself (210lbs) and a hunting buddy(300lbs), 2 marine batteries, and our gear. The 11mph was the same in 4 inches of water and in deep water...

GPS had me at 9.2 pretty steady with me(210) two buddies (220, and 310) plus dekes, guns, gear and so on with my 16hp gdlt crawfish model. Its on a 14x36 riveted Grumman. That 12 mile run took a while but we made it out with no problems.

WENT OUT TO SEE WHAT MY 16HP GD WOULD WITH A LOAD ON IT 2 PEOPLE DOG .DECOYS IT RAN GREAT 15.7 MPH BY GPS THAT GREAT. WENT IN THE MUD PLAY AROUND MARKED SOME SPOTS FOR DUCKING AND THEN I LOST MY GPS THE MARSH SUCKED IT UP.TIME TO GET A NEW ONE.

Motor is back from service by the dealer. New 9x3 prop, muffler, Tinytach and tune-up.
Tested it today. Max revs out of water. 3500
Max revs in water 2850, with 3 people in boat got 13mph on GPS.
Speed is a big improvement but the revs low by about 500 rpm?are
Had some cases when motor lost rpm at full throttle, even stalled . Need to run it with fresh gas next w/e instead old but stabilised gas to see if that helps.