Chrysler 35 HP in Boston Whaler Sport 11

[rbruce63]

What could possibly happen if I place a Chrysler 35 HP (142# with alternator) in my Boston Whaler Sport 11' in place of my actual 20 HP (72# manual start)?<br /><br />Will the transom stand the additional torque? Will the boat tip and tilt at wide open throttle? <br /><br />Could jacking up the 20 HP motor to the point of having the anti-ventilation plate level with the bottom of the hull improve acceleration and speed?<br /><br />Please advise.

 

[The Marine Doctor]

Re: Chrysler 35 HP in Boston Whaler Sport 11

Nobody here is likely to advise you to over power you boat. If the tag says 20 hp as the Max..this is what is advised...You have already mentioned some concerns. You are on the right track with them. It's all about safety.<br /><br />TMD

 

[moderator1]

Re: Chrysler 35 HP in Boston Whaler Sport 11

rbruce63,<br /><br />I believe your question may be answered more thoroughly in the Boat Questions section. The question is really not a Chrysler problem, it is more a performance question.

 

[SeaMasterZ@aol.com]

Re: Chrysler 35 HP in Boston Whaler Sport 11

as much as I slam the low freeboarded wet riding, hard riding little beasties, they ARE one of the most solidly built boats on the planet, if a decree came down where you had to have ONE boat last the rest of your life, I would probably spend it soaking wet with a sore back (or get a nice 25 Outrage, lol)<br /><br />if your boat is maxed out at 30, I dont think there is a problem, cause the tri hull design is inherently stable, and the build quality of a whaler is the stuff of legends, as long as yer solid, the transom is going to take it

 

[JB]

Re: Chrysler 35 HP in Boston Whaler Sport 11

No way would I put more than 20hp on my BW 11'!<br /><br />If your AV plate is not even with the keel you are sacrificing speed and stability. Could it be that you have a long shaft engine on it now? The AV plate should be at, or slightly above, the keel level for best speed, handling and stability.<br /><br />That hull is solid as a rock, but the extra power and weight would unbalance it and make it very squirrelly.<br /><br />Stick with 20hp, RBruce, but optimize your rigging and your prop.<br /><br />Good luck.

 

[rbruce63]

Re: Chrysler 35 HP in Boston Whaler Sport 11

Ray:<br /><br />The maximum HP for my dingy is 20 HP. I currently have a Chrysler 20 HP from 1969 that my father had in storage after using it some 5 hours. The motor is new, all right. it exhibited some problems during a 5 hour rally like guzzling close to 4 gallons per hour, close to overheating in the last leg and I decided to stop the engine, breaking the starter pinion, but that was my fault and she feels underpowered. <br /><br />I wanted to go to 35 HP manual start Chrysler of more recent vintage, but there is 1987 that is being checked in Missouri, alternator type and 140#, 70# more than my current and beloved motor but I feel that I might damage the transom or risk limb and life. I am a cautious boater but I would be lying if I said that I was not going to run it at wide open throttle!<br /><br />And yes, I rather have a Montauk 17' but can't for now, perhaps if I can sell my dingy at some affluent marina... Such is life in the tropics!<br /><br />Robert

 

[rbruce63]

Re: Chrysler 35 HP in Boston Whaler Sport 11

JB:<br /><br />My favorite teacher in Boston was called JB! <br /><br />I have the ventilation plate 1" below the hull. The motor is a short shaft 15" but I can jack it up one inch more to have the ventilation plate level with the hull at the transom.<br /><br />I will try to check RPM's this or next weekend. I live in a "continental" country so towing a trailer even for this small thing is complicated specially in the mountain roads that we need to overcome to reach man made lake impoundments used to generate electricity.<br /><br />Thanks for your advise!<br /><br />Robert