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Old 01-14-2007, 08:56 PM
LinedTheBlind LinedTheBlind is offline
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Transom Water Pick-up, Any Benifits?

I'd like to get some feedback from anyone who is knowledgable about transom mounted water pick-ups which, in conjuction with a jack plate, allow you to raise an outboard up higher to run in shallow water.

How far (inches) can the motor typically be raised up with a transom mounted pick-up? How much clearance would i gain by adding the pick-up?

I have a small boat and won't be adding a hydraulic jack plate, but could add small manula plate. Can I run at top speed with the motor permanently set at a shallow water hight?

Thanks.
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Old 01-21-2007, 03:24 PM
RAWRF RAWRF is offline
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If the plate above your prop, I can't even think of the name for it, is out of the water, you will be running on about 25% power, with no torque for going against a current, so you can only get so far out of the water anyway. I have never seen a transom intake for an outboard, so I don't know about that.
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Old 01-28-2007, 07:22 AM
Syed Syed is offline
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We have to be careful for keeping the cooling water inlet openings fully submerged, while experimenting with the height adjustments in shallow waters.
These holes are mostly located under the cavitation plate.
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Old 02-09-2007, 06:59 PM
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Quicksilver Quicksilver is offline
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Ignoring loss of power. Are you planning on high speed shallow water operation? If so you dont need a transom pickup. the force of the water on the cavitation plate would feed the cooling system. I used to run a 10' RIB with a 15hp merc and a semi-surface piercing prop. It ran about 40mph and almost completely out of the water. Guess what, no cooling problems at all. It really was running surface piercing but had no problem forcing water into the pickup, it doesnt take much.

You can just test this simply. Try it out, if water flows just as well as it did before, than why bother with all this transom mounted cooling pickup. Theres a reason the water pickup is directly above the prop, even with the prop half out of the water, your still going to get sufficent pressure. I will suggest this, if you do this, upgrade your prop, you can use a higher pitch and if you can find one, get a surface prop. Running a stock prop as a surface prop can unload the engine causing over rev and guess what, over heating the motor. You can do this, just change the prop, you might have to experiment.
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