Poor handling

[Grumpyrockfarmer]

My '69 Merc 650 is on a 14' Calypso Cutter fibreglass rated for 50. The bottom is smooth and fairly flat for the whole back half of the boat. She leans in straightaways and thrashes about suddenly in turns. Played with the non-power trim a lot. Gonna try a different prop I guess. Anyone know about these type of handling problems? What's the deal with those wings for the outboards I've seen at the dealer?<br />Boat is used for tubing on small lake. Too erratic to ski behind.

 

[JB]

Re: Poor handling

Howdy Grumpy.<br /><br />I don't know anything about the Calypso, but I have never handled an overpowered boat that wasn't squirrely, not even a Boston Whaler.

 

[walleyehed]

Re: Poor handling

GRF, I think you are attaining speeds that hull was not designed for and is creating alot of extra stern-lift, pushing the bow down. This would be the turning issues for sure and the wetted surface of the hull is more than was intended with a 50HP.<br />The only item short of removing the bigger engine and installing a smaller version would be to add a set of smart-tabs.<br />The Hydrofoil, in your case, could cause some very serious handling issues...more problems than you have now.

 

[BF]

Re: Poor handling

it's not a long shaft motor on a boat with a short transom is it? Or is it a cable/pulley steering system with lot's of slop in it?<br /><br />just a couple thoughts...

 

[Moody Blue]

Re: Poor handling

GRF, at what speeds do handling issues become an issue ? At what height is the motor mounted (A-V plate relative to boat bottom)? Did changing the trim angle of the motor make any difference in the handling ? If so how. I've got a 40hp on a 14ft hull rated at 30hp and have had no problems at all. Rock solid and stable even at 40MPH. Carves thru corners like a slalom skier.

 

[fishingdan]

Re: Poor handling

I am not familiar with that brand of boat, but another thing to check is the stringers. If a stringer or all of the stringers are failing (from dry or wet rot), the hull could be changing shape as you run. If this is occurring, this is very dangerous and the boat needs to be repaired before you run again. <br /><br />Hopefully it is not this. I too have put larger engines than recommended by the capacity tag on several boats (mostly because I already had the engines). All of my boats had good solid hulls and internal structures. In these situations, the common "over powered" symptoms were:<br /><br />1) The boat took longer to plane simply because the engine was too heavy for the back of the boat. The engine mounted fins help in this situation. <br /><br />2) At high speeds, the boat could porpoise and be uncontrollable.<br /><br />3) After going at higher speeds, if the thottle was rapidly pulled back to idle, the boat could get real squirly. <br /><br />4) Depending on the hull design, you could experience some "chine tripping". This was true for the flatter hulls that had sharp chine edges. The boat would normally behave this way, but put a larger engine on it and college student driver and you quickly need to see "what the boat could do".