Motor Height of Motor

[Senderofan]

I've been seeing some discussions about proper set up of a motor when fine tuning with props. I was wondering if any of y'all have a picture or two to show me the proper height of the motor in relationship to the bottom of the hull?? Mine is set up on the very top hole...ie...it's sitting as low in the water as it can. I'm wondering if it should be raised to help my rig run more efficiently?

Boat is a Lund 1800 Fisherman (18.5 ft) with Merc XR6 150.

Thanks in advance,

Wayne

 

[Dhadley]

Re: Motor Height of Motor

Motor height (X dimension) is based on hull design, prop design and intended useage. There is no one setting for all props on all hulls for all uses. I run a couple different props on my flats boat and they do different things. I have a hydraulic jackplate so I can move the motor at any time.

Tell us what type hull you have, what prop and what you do (skiing, running shallow, top speed only, offshore in following seas etc).

 

[steelespike]

Re: Motor Height of Motor

Usually the starting point is with the anti vent plate(just above the prop)
is even with the bottom of the boat.Sometimes it can go higher depending on the boat,motor and prop.Usually a more sofisticated prop will allow more height.If present setup is fair to poor you could gain 2 or 3 mph by raising the motor.Better mileage goes along with improved performance.
Something to consider with gas at $4+ a gallon.

 

[Senderofan]

Re: Motor Height of Motor

Thanks guys....I had thought the anti-cav plate should be even with the bottom of the hull....or I believe that's what I read here, I'll have to examine it more closely.

I am, in fact, more concerned with making sure it's as efficient as possible....with the price of gas and all.

This boat is a deep V aluminum fish and ski. We use it for tubing, skiing and fishing fresh water lakes. I've switched from a BlackMax 14.25" by 21p aluminum prop over to a Stainless 14.25" by 19p....which has seemed to free up the motor...ie, she can now get to her max WOT. Before it seemed a little sluggish and about 200 rpm below max. I don't run around much at all at WOT but the new prop makes the boat more responsive at any rpm and she gets on plane very easily now.

Thanks again for the info. I want to make sure my rig is set up to be as efficient as possible...and being new to the boating world...I thought I'd ask the experts!

Take Care,

Wayne