Boat Problem

[gator]

I realize this should probably be in in the boating section, however; I need some good advise. I own a new carolina skiff 178 DLV with a 90hp yamaha 4 stroke motor. This past week I was at the St. John's river with my father, brother, and son all on board. The boat would not plane and would only get to about 3900 rpms. One of the other men on our fishing trip said I probably needed a new prop. I did test the boat without my father in it and it jumped on plane with a speed of around 33 mph. However, I bhelieve that motor should have enough power to plane with 3 men on board. Any advise would be greatly appreciated.

[Jumptrout51]

You are either under propped...or you forgot the plug and have a lot of water in your subfloor.
You may also have a cylinder not firing.

[bman]

Skiffs are funny about breaking plane....
I have a J-16 with a 30hp 4stroke that I swear does not have the same power that it did with the old 2 stroke 25 that was on it when I purchased it.
Now- we load that boat up with tons a tackle and junk, an extra battery for the trolling motor and who knows what else.

The problem seems to be the ability of the 4storke to gain torque... If it gets on plane it fine but it can take forever.
Two guys and its fine- three and no way will it break.

Also noticing that a little ripple on the water helps.

We put on a wing and that helped, We changed props and that helped, I want a bigger motor.

The only saving grace with the 4 stroke is normally I burn $5 of gas on a trip.
Maybe slow ain't so bad.

[Barhopr]

put some Lenco trim tabs on it to push the nose down. will solve planning problem. Be sure the motor is trimmed all the way down on take off, trim up as you gain speed.

[wevans]

A 4 stroke simply doesn't have the bottom end torque I have mine propped so that I can't push the throttle wide open by myself "it will over-rev this acomplishes two things, I get on plane very fast by myself and I can still get on plan decently with a passenger and his/her stuff on board I lose a little speed and have to watch the RPMs, but it's worth it to me "the Bob's stabilizer helps a good bit also"

[Reel Cowboy]

Put some trim tabs or a stablizer plate, they'll both push the front down.

[Eerman]

Hang you dad off the bow eye and tell him to hold on. Or what they said.