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punthouse
09-29-2002, 08:43 AM
Took the 21 inch pitch prop off my 17 foor SeaRay with 130 Mercruiser. Replaced with 19 inch composite for better pull for skiing. This brand new 19 "slips" and won't even get the boat on a plane. What do I look for? I try with all my might to turn the prop by hand while in gear but can't get it to budge"slip". Thanks for your time.

wsm9808
09-29-2002, 12:05 PM
You would have to turn the whole motor to get the prop to turn while in gear. When you put your drive in gear it ingages the gears that drive the prop and makes a geared link from engine to prop. There is no fluild couple like in a torque convertor in an automatic tranmission.
[ September 29, 2002, 01:06 PM: Message edited by: wsm9808 ]

punthouse
09-29-2002, 02:50 PM
I understand but I was trying to figure out where the slippage was. I thought I would be able to make the prop slip on the shaft but to no avail.

not guilty
09-30-2002, 05:58 AM
check the diameter of youre new prop , if its smaller it could be cavatating.I know on our 23 ft boat going from a 14 1/4 to a 14 3/4 diam. made a big diff. NG

kevnmcd
09-30-2002, 07:12 AM
When you give it gas will it hook up for a second and then the rpm's go through the roof? I spun a hub once and that is what happened. It would start to get on plane and then the rpm's would just fly. Try another prop if this is happening.

TCHB
10-08-2002, 08:16 PM
It sounds like your new prop is much smaller in diameter. With your small engine package I would go with a standard 17 pitch merc aluminum prop. On a 2500 pound boat with a 350 mercury outdrive 21P prop, most people have a hard time getting to the RPM of 4800. You should always prop the boat to the engine recommended max rpm. Oh yes do this with people in the boat.