Newb needs help with 17 Pro-Am

[jezushadlonghair]

I have a 1994 17' Pro-Am with a 70HP Evinrude. My first comment is I love the boat. However, when it planes, it lists to the port side. I've tried adjusting the trim tab to no avail. I've even tried it with and without doel-fins. What could be causing it?
I also want to hear motor recommendations. The 70 pushes pretty well, I get 32 mph with 2 people fully loaded and a 19 pitch prop. Its rated for 125 and I'd love to upgrade. Are the HP ratings based on weight or speed or both? What kind of performance are other guys getting with larger motors? Thanks for taking the time to help out a newbie.

 

[jevery]

Re: Newb needs help with 17 Pro-Am

Does it sit level at rest without people on board? What type tabs do you have? Motor torque tends to tilt the boat to port when under power, but unless you're near your HP limit this shouldn't even be noticable. Isn't a 19 pitch prop too much for your boat/motor combo? I'm running a 17P on a similar boat with a 115 HP. Do you have a tach to verify your running in your target zone at WOT? As far as motor size goes I think max rated HP is based both on motor weight and maintaining a safe speed for boat design. I have a 17ft Crestliner Serenity with a 115 4-stroke. It runs about 45 mph. Your 70 probably weighs about 310 - 320. My 115 weighs 395. You could easily upgrade HP if you need more umph and have the $$$.

 

[jezushadlonghair]

Re: Newb needs help with 17 Pro-Am

At rest the starboard actually sits a bit lower, then it tilts to port under power as you described. I only have the tab that is bolted to the lower unit. Adjusting it helped keep the boat from pulling to one side, however it did nothing for the tilt. As for the prop, I'll try a 17 and see if there is any difference. The 19 was on it when I got it and I wanted to see how it performed, this is my first season with the boat. The tach reads 5100-5200 at WOT. Thanks for the info.

 

[rndn]

Re: Newb needs help with 17 Pro-Am

Did the 17" prop help?

 

[jezushadlonghair]

Re: Newb needs help with 17 Pro-Am

I've actually only had the opportunity to use the boat a few times this year and I haven't tried the 17. I contacted Crestliner who said the hull could be warped or the transducers could be mounted too low. I don't know about the condition of the hull but Lowrance recommends mounting the transducer below the hull for best results. The boat is in the water right now, when I pull it out in a few weeks to prep for our big Canada trip I may try a few things. They also recommended trying some aftermarket trim tabs on either side of the transom. I can actually live with it but my girlfriend is scared to sit on the port side when we're cruising.

 

[jezushadlonghair]

Re: Newb needs help with 17 Pro-Am

I have an update for those following my saga...(probably just me). A friend of my father who is a longtime marine mechanic and performance boater took a look at the boat this weekend after I pulled it out of the water. He saw that the previous owner installed three transducers on a block on the starboard side of the transom, a convenient idea but it wasn't installed flush with the angle of the hull. Essentially it appears as though it was creating a trim-tab like effect, lifting the starboard side. I have removed the block and remounted two transducers, one wasn't being used anymore. He also wants to raise the motor 1-2 inches on the transom which we'll do after I get my custom cover installed. Hopefully I'll have a level-riding boat in a few weeks.

 

[rndn]

Re: Newb needs help with 17 Pro-Am

Good luck!

 

[jezushadlonghair]

Re: Newb needs help with 17 Pro-Am

With the block removed the boat rides perfectly level. We didn't get the chance to raise the motor but I still want to do it. The 17 pitch prop did give me a better holeshot, at least it feels like it. However, I'm still looking for an early to mid 90's 120 looper for the ultimate upgrade...