water coming over my transom

[BUDDY123]

I have a 14' Alum V rated at 600lb and 20hp. Just changed motors from a 6hp to a 20hp. Weight in rear is 115 motor and 200 me (315 total). Weight forward is gas,battery, wife, about 250 total. Anti Vib plate is even with bottom of boat. Breaking in new motor at 1/8 speed everything seemed ok. Now at 1/4 speed and water is spilling over the transom.I can"t arrange weight any different, not sure what else I should try. Was thinking about making some sort of transom splash plate, but want to make sure I dont have another option or problem. Buy a new boat is not one of them. Thanking everyone in advance.

 

[Stumpalump]

I had a boat that had a similar problem and I was sure it was going to get swamped one day. After a while of learning how to regulate the throttle to keep the boat in its sweet spot it was not a big deal anymore.

 

[UncleWillie]

Go faster! And trim the engine IN farther. Bow Down, Stern UP.

Low throttle just before getting on plane is the worst position to be in.
You will be pushing the largest bow wave possible and the stern will sitting as low in the trough as it will get.
The motor will also not be able to make good RPMs and be working very hard trying to lift you up.

Get on plane, and the stern wash will be left behind.
Pay attention when you come Off Plane as the Stern wave make catch up with you and swamp your behind.
Welcome to the fine details of seamanship.

 

[BUDDY123]

Still confused or maybe I didn't state my problem correctly. The water is coming in the back of the boat at the higher speed. It's as if my transom is to short or setting in the water to low. The water splash is be generated by the engine. So what your saying is I should tilt the engine closer to the boat??

 

[smokeonthewater]

Yes if possible the lower unit needs tilted closer to the boat and you need to give it more throttle to 'push through' that situation.

 

[Expidia]

This is the problem and safety risk with crafts with low freeboard (inches from water to top of the gunnels). I've had several boats like that. Was the older motor a 2 stroke which is lighter than 4 strokes? One solution I used was to move myself up to the middle seat and use a tiller extension if your outboard is a tiller? http://store.minnkotamotors.com/category/392905/tiller_extension_handles

 

[Mel Taylor]

It's still not clear to me exactly what's happening. Do you mean that a spray of water is splashing up into the back of the boat from behind as you run at high speeds? Or is the boat riding so low in the back that the transom is below the water level of the lake or stream you are boating in at high speeds?

If water is splashing up in a spray (commonly known as a rooster tail) and you have a transducer or anything else mounted on the transom, that may be the cause of the problem. Here I speak from experience because I had that trouble. My solution was to move the transducer over to a few inches farther away from the propellor. Another way is to construct and mount a shield made from pcv pipe above the transducer (or what ever is causing the problem) to avert the water downward as it tries to splash up. I didn't use this solution because the turbulence from the prop was interfering with the reading of the depth finder and I didn't think a shield would solve that problem. I searched here on iboats and found two or three good threads on constructing a shield.

If water is coming over the transom (or threatening to do so) because the back of the boat is setting too low in the water the solution may be a bigger boat with higher load capacity.

EDIT: I just searched the forums for "rooster tail" and turned up 500 posts on the subject. If your problem is a rooster tail, buried somewhere in all that information should be the solution to it.

Good Luck.

 

[Stumpalump]

Is your new engine a long shaft on a short transom?

 

[Mel Taylor]

Is your new engine a long shaft on a short transom?

I'm not sure that would make a difference. I've used long shaft motors on two different 14' tinnies with short transoms at various times and while it made the steering a little weird, especially on turning at high speeds and may or may not have cost me some MPH at WOT, there were no problems with splashing water over the transom or the stern running any deeper than with a short shaft motor.

 

[smokeonthewater]

You probably weren't MAXING your boat's weight capacity or motor weight/size... too long of a motor is a bad deal...

I suspect tho that the O/P is just inexperienced and afraid to get over the hump so to speak... also possibly trimmed too high as well.

 

[Mel Taylor]

You probably weren't MAXING your boat's weight capacity or motor weight/size... too long of a motor is a bad deal...

I suspect tho that the O/P is just inexperienced and afraid to get over the hump so to speak... also possibly trimmed too high as well.

You are right in that I wasn't even close to maxing the weight in either case but I was maxing the engine's HP in both cases. IMO, if the boat is at max weight capacity it's potential bad news regardless of the size of the motor.

 

[BUDDY123]

Short shaft motor is correct for the boat, I will play with the trim next time out. As per my post I'm probably to close to max weight for the boat. Guess I have to start looking for something that can handle more weight.

 

[Stumpalump]

You probably weren't MAXING your boat's weight capacity or motor weight/size... too long of a motor is a bad deal... I suspect tho that the O/P is just inexperienced and afraid to get over the hump so to speak... also possibly trimmed too high as well.

Over the hump is a good call. How many times have we jumped in a new guys boat only to show him nothing is wrong. I had a buddy with a beautiful Youngblood with a 150. He never did more than 30 all summer. First ride, I hammered right thru the hump and it was worse than most but the look on his face was like I just gave him a new boat. I did!

 

[airshot]

Are you meaning that spray from the motor is splashing over the transom or do you mean water from wave action is coming over the transom? If you are concerned about spray created by the motor running fast, it could be the AV plate causing that. If you are getting spray over the transom when running fast you might try one of those add on whale tail gizmos. I had a 14 with a low transom and when on plane some spray would come over the back into the boat, as a tool maker I was able to make my own from a piece of stainless steel and the larger AV plate made a big difference and stopped the spray. If lake water is from wave action is coming over then you have a weight transfer problem as others have suggested.

 

[BUDDY123]

No its not wave action. It's simular to when I tested the motor in a large garbage can, when I ran it a higher speed it would roll over the top of the can. Almost the same when I run it at 1/2 trottle it seems to roll over the top of the transom. For my next trip I have removed the trolling motor and battery, placed an addtional 30 lbs forward and titled the motor closer to the boat. I also made to plastic splash guard that I temp attached to the ransom inorder to deflect the water.

 

[steelespike]

Are you sure the motor is a short shaft on a short transom.Anti vent plate just above the prop "about" even with the bottom of the transom.
Ive run some pretty loaded boats that wouldn't come close to planing never came close to coming over the transom(short transom).
Some times when cutting the throttle to quickly a minor splash over the transom.
Does the boat have a floor with foam underneath? Sometimes the it absorbs water adding a 100 lbs or more near the transom.

 

[crabby captain john]

It sounds like a weight problem. If the boat is older and rated for a 2 stroke 20 you have additional weight with a 4 stroke.

 

[BUDDY123]

Motor is correct, no floor. Yes it is an older boat, never thought about the rating 20 years ago (Dah). Removed battery and trolling motor, moved gas tank forward and formed a splash guard. Hopefully ok until I find a higher rated weight unit. Any suggestions since I have a new 20HP to put on it?

 

[BUDDY123]

Problem solved, just purchased a 16" Alumacraft rated at 890lbs with 1961 Johnson 10hp(not sure if it runs) trolling motor(runs) and fish finder but needs power cable and trailer for $300+fees. Might keep the 14' and keep the trolling motor with some lakes around here in PA that only allow electric. Hopefully I can get the Johnson running and recope a few bucks.

 

[jbcurt00]

Where in PA do you hail Buddy? Got any pix of the 14ft'r & 10HP Johnson (& it's serial#?).