how do you determine where the motor should be set

[keithm1961]

I have just installed a 1976 85hp Johnson on an 18ft 1979 BAJA.
At some time in the past It has had a Johnson on it so the holes were there.
The transom is very thick and I couldnt get the motor in the top hole. So I put it in the second hole. MOunted up just fine. On the test run all seemed well. I noticed the water ,at speed, is at the lip where a whale tail would mount. when at a dead stop if you go to full throttle while turning it almost sounds as if its cavitating, the motor seems to rev a little higher. In a straight line I dont hear the reving. How do I know the motor height is correct

 

[Bob_VT]

Re: how do you determine where the motor should be set

The cavatation plate should be about even with or about 1" higher then the keel.

In addition..... you may be running the wrong prop...... what does the tachometer say at wot?