'95 Whaler, dauntless 17 motor setup(speed problem)

[SCO]

This is a new boat for me, and according to a review, with a 115 motor, the tester was getting 46 mph, and into the 50's with a 125. This boat has a 130 evinrude looper('95). Measured the transom at 20 inches, and the cavitation plate about the same or a little less from the top of the transom. The prop is about 14.5 diameter(measured) and the pitch is 21. Gear ratio is 12:27. The tach reads 6000 at wot, and it sounds like it is rapping out, but top speed though is about 36mph. <br /><br />I checked the pulse switch and confirmed it at position 6 per Dhadley. It didn't seem though to "click" into position. My partner earlier put a whale tail like fin on the cavitation plate because it was difficult to get on a plane, and it gets on plane fine now. I also used a centerpunch to dot the hub and prop and determined that the hub is not spun. <br /><br />This is what I would call a deep v hull. I calculate losses at some 35%. I suspect the prop is not far enough into the water and is partially cavitating or not geting enough bite.<br /><br />Any suggestions on how should set up this motor? Should the motors on deep v's be set lower? Thanks

 

[crazy charlie]

Re: '95 Whaler, dauntless 17 motor setup(speed problem)

What is the condition of your boats bottom??Fouling growth will slow a boat tremendously.

 

[SCO]

Re: '95 Whaler, dauntless 17 motor setup(speed problem)

It hangs on straps, and someone let a strip touch the water, and there is a strip of growth. They say it has never performed though. I'll get the growth off asap. Becauste of the trouble getting on plane without a fin, I strongly suspect the prop is not pushing hard enough, in the same way that a tunnel hull doesn't go as fast as a v. How do you deep v owners have your motors set up? How far below the keel is your cavitation plate( with trim set parallel to the keel). Thanks if any can help.

 

[BillP]

Re: '95 Whaler, dauntless 17 motor setup(speed problem)

It's a guess to me: <br /><br />The rpms are about right so you may need to go down in prop diameter and up in pitch to get more speed. Having the motor a little high USUALLY results in faster speeds, not slower...especially with the "whale tail" which helps reduce cavitation(some call it ventillation)on elevated motors.<br /><br />Have you weighed the boat to make sure it is close to the mfgs specs? Like all boats with foam, it may have sucked in some and added weight. 30-40 gals would make a lot of difference in speed. I've seen 300lbs of wet foam pulled from a 19'Mako.

 

[SCO]

Re: '95 Whaler, dauntless 17 motor setup(speed problem)

Haven't weighed it. Good suggestion . Thanks Bill.<br />I talked with a Bombardier rep yesterday and a Boston Whaler rep. The Whaler rep was not insightfull in the least, but the bombardier rep impressed me. He asked if the boat started porposing immediately when trimmed out to speed. I have noticed it does this. To him this indicated that the boat is not getting on the "pad". He suggested I lower it down a notch and that will allow a little down trim to find that "Pad"