Moved tower of power from one boat to another now it won't run wide open on water

[Ericbarner39]

so I bought a deck boat and moved my 1150 to it starts and runs fine but it won't plane out at WOT no matter where the trim is ive tried to adjust the air screws out and in same on all three no change I dropped .y wife off at the dock to go to the car and was able to get it to slowly crawl to a plane and then everything seemed good went back picked her up back to no plane 3000rpms WOT 10mph or less all day I'm really bummed that engine ran pretty problem free for five yrs including 2 weeks ago on my other boat now I don't know what to do it has a 17p prop and 13x1 is stamped on it PLEASE HELP

 

[emoney]

To help others; what boat was it on before? Are you certain the new to you boat isn’t waterlogged and thus too heavy? No fuel system leaks, bulb collapsing etc?

 

[Chris1956]

Some of those deck boats are pretty heavy. You may just have too much pitch on the prop.

Alternatively, make sure the throttle linkage, pulls the carbs all the way open. It makes sense to take a compression test and a spark test. Inspect the spark plugs while you have them out. They should all be the same kind of dirty.

Brown and black are acceptable. Grey or real clean indicate water in the cylinders.

 

[Ericbarner39]

Previously it was on a 16.5 fiberglass tri hull about a 1000lbs now there boat weighs atleast 2000 lbs I checked the throttle definitely wide open i changed the plugs with brand new ngk BUHW no water on them checked twice on the lake and it definitely has spark that thing hit me hard when I stupidly held the wire to check like I almost fell over I was thinking the prop shouldn't be too much but I guess it could be it just felt like the motor wasn't even trying to push past like 2800 rpms it would get right up up to that rpm then would lay over and not go any further maybe 200 rpm higher if you squeezes the primer bulb i would sputter too much fuel same result if id tap the choke while underway is a 17 pitch prop too much for a heavy deck boat ??

 

[Texasmark]

My experience with 2 strokers in fine working order, and I had an 1150 (and currently have a 115 4 cyl. looper) that I ran regularly up to 6k rpm, is that when you overload them they just puke.....(fall on their face). Put the right pitched prop on and and hang on. Proved it more than once.

 

[Ericbarner39]

My thoughts also do you have a recommendation I tried posting in the prop section haven't had any luck parts guy at bass pro reccomended at 13pitch by 13.75 diameter but he also admitted no ever hearing of a mercury 1150 so idk also I tried to find that online and can't but he sure had one

 

[Chris1956]

Mercury and others have prop calculators on their web site. See what pitch it recommends for that motor and boat.

Model number 1150 is an old term, and I will bet your parts guy is not.

 

[Texasmark]

T

Mercury and others have prop calculators on their web site. See what pitch it recommends for that motor and boat.

Model number 1150 is an old term, and I will bet your parts guy is not.

This is the one I use: https://www.go-fast.com/Knowledge-ba...lip-calculator

Gear ratio is just the number like 2 for a 2:1 ratio, common on that engine
RPM and Pitch are numbers
Push the Theoretical Speed button. The answer is what that "screw" would be doing if turning in a solid...like wood.
Next plug in your actual speed and push the Slip button.

Single digit slip is for a fast hull/engine combination. The slower you go, the higher the slip. If you are running up in the 30% area something is dreadfully wrong or you are trying to push a barge.....if occurring at WOT RPM.