90 horse Johnson Stability Question

[zonaman]

Just got back from the lake where I took my '59 Dorsett with the 2000 , 90 horse Johnson out for the first time. It got up out of the hole very quickly and planed out nice. Then at about 4000 rpm about 30 mph, the steering would go loose and it would turn to one side, when your correct it by turning back it would pull to that side. Adjusting the trim/tilt mad little difference. Make its quite unstable at high speeds. I've included a few photos so you can see how she sits in the water. The cavitation plate is even with the bottom of the hull about 12" below the waterline on the transom. Any suggestions on what the problem might be and how to correct it?

Thanks.

 

[tashasdaddy]

Re: 90 horse Johnson Stability Question

are you saying the motor turns by itself with you holding the wheel? what type steering are you using. see if it is the steering, or the motor. was the motor a salt water motor before?

 

[zonaman]

Re: 90 horse Johnson Stability Question

are you saying the motor turns by itself with you holding the wheel? what type steering are you using. see if it is the steering, or the motor. was the motor a salt water motor before?

The motor doesn't turn, it seems pretty stable, but the boat turns as if it were plowing but it's up on a plane and I have it trimmed nose up. It's a Teleflex rotary steering system, new cable.

 

[tashasdaddy]

Re: 90 horse Johnson Stability Question

i would check for unwanted wanted water aboard. also you want you hull to plane out almost level, bow too high, it pivots on its tail. it idea of trim is to throw the bow down to plane. when you take off, you start with the motor trimmed all the way down, as it throws the bow down, you then trim up on the motor.

 

[zonaman]

Re: 90 horse Johnson Stability Question

Would it help to place some weight in the bow? Most of the weight is near the transom. Also there was some water getting in somewhere the bigle pump went off after a couple of hours. Still checking for where leaks are.