14' "olympic" stern heavy

I have a 1975 14' Olympic fiberglass boat with a 40 hp johnson. We took it out yesterday for the first time and it seemed to be stern heavy. I was expecting it to go a little faster than it did. When an adult sat on the bow it seemed to go better. Any ideas as to the correct outboard height etc to get better performance ?? Also I guess these boats are no longer made and I cannot find any reference material on them.

Re: 14'

Re: 14'

If the motor tank and battery are all in the stern it would be stern heavy.If the hull or flotation foam have absorbed water it may be heavy in the stern,If the motor is trimmed out too far it might feel like it is heavy in the stern.If the motor is out of tune or not getting full throttle opening it might appear sluggish or stern heavy.
You might start by checking for full throttle and see what the compression is.About 100 psi and within 10% cylinder to cylinder would be good but it will run on less
with less power.You might check to see how it reacts with one plug at a time unhooked.
It would be excellent if you could check the rpm and get a GPS speed reading.That boat should feel pretty quick with a properly set up healthy 40 hp.

Re: 14'

Re: 14'

Thats what I though, I am going to get the manual for the engine and give it a good checkover. Also the motor came with rubber "fins" or protectors. I am wondering if they may actually be pulling the rear down under power, and you are right, the tank and battery are all in the rear.
Thanks

Re: 14'

Re: 14'

The "fins" are a hydrofoil stabalizer. Apparently, the previous owner had similar issues and installed the hydrofoil. Once planed out, the fins should be out of the water. You will definitely want to move as much weight forward as possible. The hydrofoil may be helping to plane you out, but they can often cause some negative effects. Trim tabs are a better option for performance. Definitely check for waterlogged foam below deck, tune the motor, and distribute the weight more evenly.