Boat won't plane out

[Zachb6]

Ok so I've had my boat for a few months and some background it's a 1990 kingfisher 179v with a 1990 Suzuki 150hp two stroke motor and I've had it out many times and have loved the boat so far. The motor runs like a top I'm really impressed it starts right up it runs great but the one problem I have faced is the boat will not plane out. I have put the throttle to the floor and the bow gets extremely high in the air which I get is typical but it will never get onto plane and I'm wondering why this is happening. 

[gulfcaptain]

You have to trim it ALL the way down first before you take off, then as the bow drops you slowly trim the motor back up to bring the bow up and the boat on pad.  Of course if you motor doesn't have hydraulic trim, well you're going to have to drop it to a position where you loose speed or get your buddy to run to the bow when you take off till you're up to speed to help the bow drop.

[Zachb6]

I have all the trim set right my dads had boats and tried to get it up to plane but it doesn't want to get up over the wave I'm almost wondering if it doesn't have enough prop or if it has too much prop

[slonezp]

could be prop, could be height. With the boat on the trailer and the motor trimmed down, where is the cavitation plate height in regards to the bottom of the hull(pad)? Is it even with it, above it or below it? and if it is above or below, what's the distance? What are the RPM's at WOT?

[Zachb6]

I'm not sure what the cavitation plate is haha new to boats this is my first real boat and the rpms are also unknown because the tac doesn't work 

[Kevin22]

Prop wont cause the bow to go up. Bow going up is your motor tilted too far up. Trim it all the way down, and if it still wont get up on plane then you have issues. Motor height or prop. 

[Zachb6]

Ok I'm going out later this week so I'll give it a try thanks for all the help and I'll report back hopefully with good news after I get onto the lake!

[GetJigginWithIt]

You launched the boat off the trailer right? Just joking. Maybe prop hub spinning out.

[WIGuide]

Has it planed out since you've had it, or did this just start happening? Do you rpm's jump way up, or does it just kind of bog when you drop the hammer to take off? I know you don't have a working tach, but you should be able to hear it. If RPM's continue to rise, it's very likely a spun hub. If it' bogs it's either way too big of a prop, or engine issues. As people here have said, make sure it's trimmed all the way down. Other issues that can cause it is having a ton of weight in the back of the boat, also make sure there's no water in the hull as that can prevent you from planing out as well. Report back with what you find.

[Zachb6]

It hasn't planed out because this was the first time I've put it on a lake without a speed limit and the engine does sound healthy and rpms sound fine when I step on it but now that I think of it I do have 3 batteries in the back of the boat and my anchor and I had a full livewell at the time so maybe I can move the anchor up front and take out a battery and see if that helps 

[Kevin22]

What prop is on it? 

[Zachb6]

1 hour ago, Kevin22 said:

What prop is on it? 

Hahaha how do you find that out I'm not totally sure?

 

[gulfcaptain]

Sounds like you are totally new to this.  The lever/button on the throttle is your tilt.  Before you take off make sure your motor is tilted all the way down.  Now as you speed up slowly tilt the motor back up after the bow has dropped down and that will speed you up once the boat is on plane/pad.  You can find out what the prop is by looking at whats on the hub of the prop.   

[Kevin22]

The model will be etched into the side of the prop. The size will be on the hub inside of the prop. Should say something like 14X21, two numbers with an X in the middle or a number with a P after it.. like 21P. That tells you the size of the hub and the pitch of the prop. 

[Zachb6]

I know how to throttle up the boat I'm not that dumb haha I'll look on the prop hopefully tonight and let you know what I'm thinking Is a combination of too much weight in the back and too much prop 

 

[Bob C]

I bought a Javelin a few years ago with the same problem. Turns out it had the wrong prop from a smaller lower unit. The opening for the exhaust was too small and was blowing exhaust on the outside of the hub causing an instant cavitation. 

[Zachb6]

Ok so I looked at my prop today and the size it said on it was *** I'm not sure if that helps anyone diagnose my problem any better but here you go

 

[WIGuide]

It might be easier if we can see what it said instead of stars haha

[senile1]

I don't mean to harp on the trim/tilt of the motor if that isn't the problem, but since you say that you know how to trim the motor are you sure your trim is working?  When you look back at your outboard with the trim all the way down, the top of your outboard should appear to be tilted slightly away from the boat as in the diagram below (See the vertical line showing the tilt of the outboard).  Once it comes out of the hole and goes on plane, then you trim it up which tilts the top of the motor back toward the boat while moving the prop away from the boat.  Again, sorry to keep emphasizing that if you are sure your trim is working properly.

[WRB]

Zack everyone is trying to help you understand what trim down means. Your OB engine has electric trim that allows you to trim it up to put it on the trailer, you do that....trim it up using the trim switch? If you trim it up, then you can trim it down all the way until it stops, that is trimmed down position to get the boat onto plane. After the boat is on plane you trim up the motor slowly until it's reaches speed, but not too high!

Your dads OB's may not have had electric trim, older engines had fixed pins to adjust trim.

If you know about trim and the boat still doesn't plane then the poor hub clutch is spinning or the pitch is too high; 150 hp is usually  13-14D X 22P, 3 blade SST or close to that.

Tom

PS, drain the livewell, should be empty when problem solving.

[Kevin22]

14 hours ago, Zachb6 said:

Ok so I looked at my prop today and the size it said on it was *** I'm not sure if that helps anyone diagnose my problem any better but here you go

 

Because it starred you out i would guess you had the number thirteen in there.. So thirteen X 19 maybe? 

[Zachb6]

For some reason it didn't put the numbers in haha it said fourteen dash one but with numbers (for some reason it won't let me put the numbers on this site) on the prop hope that helps out and I do understand you guys are trying to help with the trim and it's partly my fault for not clarifying this earlier but when I trim the motor down I trim it down till it stops so it's trimmed down all the way 

[Wayne P.]

23 hours ago, Bob C said:

I bought a Javelin a few years ago with the same problem. Turns out it had the wrong prop from a smaller lower unit. The opening for the exhaust was too small and was blowing exhaust on the outside of the hub causing an instant cavitation. 

That is intentional for some setups. You run a small hub prop to get prop cavitation to get the rpms up. Some props do that with vent holes in the barrel. After you get on plane, that affect is nill.

With the Javelin I had, I used a full size barrel prop when fishing alone and a small hub prop when someone was with me for tournaments.

 

[J Francho]

I think you have a spun hub.

[Zachb6]

What exactly does that mean?