Tilt Trim Question

[06 silverado]

I believe this is my problem I just want to confirm with you guys.

By the way hi guys Ive been lurking the forum for the last few weeks since I got my new to me boat. its a 16 ft 1979 Alumacraft Flat Bottom John Boat and its 5 1/2 ft wide in the back with a 1976 40 hp Evinrude,the boat has a side console in the middle of the boat so the passengers sit up in the middle towards the front when there are just two people in the boat the boat has a bench in the back and one up in the middle and there is a deck up front

Well after rebuilding the carb and fixing the motor from flooding out from a swelled up Cork Float I have taken the boat out on the river with calm to no chop water loaded down with a full cooler chairs water toys and 4 adults last sunday the motor ran fine and we have no problems tracking or anything. With my fuel problem fixed the boat even seems faster than it did before even with 4 adults and gear loaded up.

Fast forward to tuesday night me and my buddy went out for a late night cruise on my dads lake, we went out and cruised through all the lakes on the Lake conway chain of lakes and were out for about 2 and a half hours no problems at all boat ran fine it just doesnt like to Idle but I can bump up the throtle a little and it wont sputter at all.

Then last night after work I took my girlfriends Granddaddy out on a lake over by my house in winter park. It was a little windy so there was a little chop out nothing to serious. Well we were cruising around and When I would go fast it seemed like the rear of the boat was lifting out of the water. The exhaust would get alot louder like it wasnt fully submerged in the water and the boat would slow down like the prop was slipping. Tuesday night the only extra weight we had in the boat was a cooler with drinks no ice just a 12 pack of soda. and last night it was just us and a tank of gas in the back like usuall. I even had Grandaddy sit in the back and it still did the same thing.

My buddy thinks I should tilt the motor back one pin and it should get better. as of now the boat is automaticaly planed out when you take off the nose doesnt lift or anything. just take off and go. the only time it has had the nose come up was last sunday with the 4 adults and all our gear but it planed out in a few seconds.

Any Ideas would be greatly appriciated Thanks in advance

 

[gazza2007au]

Re: Tilt Trim Question

is your motor locking in once in the down position? if it doesnt lock in the motor might be tilted up more sitting on the lock rather than in the lock resulting in your motor being tilted up more or u could have alot of weight up the front of your boat lifting the prop out of the water? another thing your prop could be slipping?

 

[06 silverado]

Re: Tilt Trim Question

yeah it was locked in, So if I plan on having a lighter boat I should tilt the motor back by moveing the pin back a hole?

or you think the prop may be actually slipping? what would cause this? should I take to prop off and check the shear pin?

 

[gazza2007au]

Re: Tilt Trim Question

it could be your prop since the motor didnt have this problem before what happens is the rubber bush inside of the prop spins causing the motor to rev as there is no load on the prop as its slipping ive had this problem once but we bairly made it back to the boat ramp took along time at idle anything above would be like neutral changed prop problem solved it also could be the wrong pitch prop i was recently out in my cousins new center console tinny with 4 adults and when we turned sharp the prop would cavitate and cause the motor to rev slightly higher than the second we straiten up the boat would jerk forward and the power would kick back in