Taxin_That_Bass
Member
- Joined
- Jun 23, 2017
- Messages
- 18
- Reaction score
- 0
So i purchased and installed a CMC PT-35 on my 1972 Polarcraft jon boat. The motor is a 1981 Evinrude 35HP model # E35RC1G and I am struggling a bit with the engine height. The manual on the PT-35 says to mount motor with the cavitation plate 1" to 3" above the bottom of the hull. I mounted the PT-35 as high as i could on the transom and at that position the cav plate is about even with the hull. I test ran it at this position and it goes about the same speed as it did before i added the trim kit, but the odd thing was this motor has like a second cav plate located a few inches higher than the true cav plate. At this position the 2nd cav plate was getting water over the top of it and spraying quite a bit, so i tried raising the motor. This motor only has clamps and 1 bolt hole on each side, so i used a shim to raise it about 1 3/8" which is about max that i could do while still using the clamps. I ran it last night and at this position i lost a little speed and RPM, it felt like it wasn't getting the nose up enough. I also noticed i could see the true cav plate and looked like water was flowing good into it, however the 2nd cav plate was having water hit the bottom surface of it and it was sort of spraying it down and outward.
I think the sweet spot may be between these two positions, i'm thinking i want the water just kissing the upper cav plate? Thoughts?
I think the sweet spot may be between these two positions, i'm thinking i want the water just kissing the upper cav plate? Thoughts?