having troubles planeing???

[dave69larson]

I have a 18' fiberglass 1969 larson with a 120 hp 2.5L 4cyl inboard. I have a couple of different props for it a 14, 15 and a 17 pitch which would be the best one to use?? I have the 14 on now and with two people in the boat it gets up ok and does about 25 mph at around 4500 rpm, with 4 poeple in the boat it will not go past 3500 rpm and will not get on plane. How fast should this boat go?? I think I am getting a bit of water in the back of the boat but even with it empty it still has a hard time. Any suggestions Just did full tune up points condenser cap rotor wires plugs and coil.

 

[gprince]

Re: having troubles planeing???

Trim tabs will help it get up out of the water. I tried a different prop the other day and it was a snail out of the water but finally hit 55 MPH at WOT.

 

[dave69larson]

Re: having troubles planeing???

My boat does not have trim, is that something that I can install???

 

[gprince]

Re: having troubles planeing???

Yes. Check out the other thread called, "Smart Tabs on my Larson 208 LXI - WOW!" for more information. The Smart Tabs are less than $150 and you can install in in less than an hour. Their main purpose is to control bow rise, thus making you plane quicker and will give you 2-3 mph at WOT.

 

[dave69larson]

Re: having troubles planeing???

Thats awesome I think I will be getting those shortly. Does anyone have a clue at what rpm should be at wot????

 

[gprince]

Re: having troubles planeing???

I'm thinking you should be close to your RPM limit at 4500.