struggle to plane

[haulNit4u]

86 Merc 120hp i/o. boat runs great but will not get up on plane quickly. Also it is very hard to pull A skier out of the water because it is sluggish. once on plane it will run fast, until I back off of the fuel and then the nose comes up again. any ideas Thanks

 

[vipzach]

Re: struggle to plane

Welcome to iboats! Do you have alot of people or weight in the back of the boat, what prop are you using? These questions are assuming the boat is running right.

 

[tommays]

Re: struggle to plane

you will need to give your WOT (wide open throttel)<br /><br />and the current prop your are useing<br /><br />i can tell you right now if your going to ski on a 120 you will need some type of trim tabs <br /><br />i use a simple doel-fin on mine and it works fine other people like real tim tabs like smart tabs<br /><br />you are also going to need to use a smaller than normal prop if you want to get the skier up quickly<br /><br />it will limit your top speed but with a small motor you have to make trade offs<br /><br /><br />tommays

 

[jmccall001]

Re: struggle to plane

How about any growth on the bottom? Is it in fresh or salt water?

 

[haulNit4u]

Re: struggle to plane

Not sure of rpms @ WOT,prop is 17p and there is some weight but not alot (2 adults 1 child).I had no problems with my 22 ft starcraft cuddy with 120 hp, pulling skiers. bottom is clean and engine runs good. I am stumped

 

[retodd]

Re: struggle to plane

Recommended WOT on this engine is 3900-4300, i also am running a 17p and am able to pull about anything I want. Now granted my boat is a 1986 Glasstream 152 Tempest so there isnt a bunch of weight to the hull, but you should be able to do it no problem.

 

[xltier]

Re: struggle to plane

could be your water logged in the back.i had that once and i got a whale tail.it really helped get up on plane quick.later i fixed the wet floor.u really need to check wot rpms.possibly a 15 pitch prop is needed for skiing.just my experience.hth

 

[86bayliner]

Re: struggle to plane

ok , not sure if this will help, but on my outdrive, I have an adjustment pin in the transom shield, may be shifted to obtain proper boat trim, boat up or bow down for proper planing.<br /><br />If the boat has a tendancy to over plane bow seems to be down, shift the pin to the No. 1 position which is on the inside closest to the transom, <br />If the stern seems to be down and fails to rise for proper planing, shift the pin to the No. 3 position which is on the farthest outside. The No.2 position is the normal operationing position.<br /> <br />Hope this helps you, just learned not so long ago myself.<br /><br /><br />-----------------------------------------------<br />86bayliner