17CC Planing characteristics

[Tomroyston]

Hey all,

I have a 1999 Logic 17CC with a 90 HP Johnson. It planes and rides perfectly until I go thru 4000 rpm. Then the boat "rolls over" and goes bow down to where the front of the hull contacts the water and affects my steering as well as an obvious loss of speed. (Yes, the motor is trimmed up to the maximum) Has anyone out there ever heard of this issue or have any suggestions? I've tried a variety of aluminum and ss props in a variety of pitches. The best performance I've found is in a 19" Michigan Apollo prop. I really don't want to put 300 pounds of lead in the tail end if I can avoid it!

Thanks,

Tom

[Jim Jenkins]

This does not compute for me. Not doubting your experience. I will be using my 2002 170 CC w/ 80 hp. 4 stroke Yam quite a lot over April-June. I will watch for yours and other posts on unique handling experience and post feed back. I do have a Doel Fin and Bennets from original purchase. I can set the the trim tabs in the "up" position but the fin stays on.

I'll let you know.

[Putershark]

Over the years and the site search tool may help, I have seen different posts on hull deflections (mostly 15 footers if I recall correct) that were causing some strange running conditions at speed. I would...

1. Search out those threads and see if you can connect the dots
2. Poll the guys on which hole they have their engines mounted on their 17 footers?
3. Poll the guys on which props they are running for it sounds as if you are creating a lot of stern lift?
4. Call Dick at Merritt Marine and see if he remembers anything strange about those older 17 foot Logic hull that may create such? I would also ask him about #2 and #3 above

[Tomroyston]

Thanks for your input Putershark and Jim. I'll check more threads and report back with results as they occur. It got mighty cold after our 81 degree record of a couple of weeks ago, so weather will be a hinderence over the next few days...