Feels Like Prop Is Slipping

(rochodl) · (rochodl) **Join Date: Sep 2006** 05-29-2007, 7:28 AM

I have a 2002 Supra Launch Direct Drive. Just dropped it in the water after having my prop refinished. Runs fine when traveling at slow speeds but when coming out of the hole it does not seem to be getting up to speed the way it normally did. Kind of feels and sounds like it is spinning out like you would in a truck with the back tires spinning. The rpms are way up but the boat is not going as fast as it should. Any help would be greatly appreciated.

(yosquire) · (yosquire) **Join Date: Jun 2005** 05-29-2007, 7:48 AM

Are you sure you installed the keyway?

(flux) · (flux) **Join Date: Jun 2003** 05-29-2007, 7:49 AM

Sounds like they messed with the pitch.

(rochodl) · (rochodl) **Join Date: Sep 2006** 05-29-2007, 8:48 AM

the keyway ??

(yosquire) · (yosquire) **Join Date: Jun 2005** 05-29-2007, 8:56 AM

The keyway is a small square piece of metal stock. it's square, about 1/4" x 1/4". It keeps the prop from spinning on the shaft.

Here's the slot that the keyway sits down inside:
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Keyway looks something like this.
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(dkjbama92mariah)

The slot is the keyway; the metal bar is the key.

(rochodl) · (rochodl) **Join Date: Sep 2006** 05-29-2007, 9:03 AM

I will check that out today !! Thank you soooo much for the help everyone.

If the keyway is installed what else should I check for ??

(flux) · (flux) **Join Date: Jun 2003** 05-29-2007, 9:14 AM

If all you did was have the prop redone than it's either the key, or they put a different pitch on the prop when you had it reworked.

Who installed it afterwards??

(rochodl) · (rochodl) **Join Date: Sep 2006** 05-29-2007, 9:19 AM

My Buddy B-Dog did !! Not sure he knows what he is doing !

ejojprop 05-29-2007, 12:06 PM

Could be some of the cup was removed in the repair process. This will cause the propeller to feel like it has no "bite" and run high RPM with a reduction of speed.

(lightningstrikes)

If I had to guess I would agree that the key is the problem. It is actually called a woodruff key, and it is very important you don't just buy any key. You should use the correct one for a propeller shaft...it is able to shear down the centerline in case of a prop collision, thus allowing the prop to stop and take the damage rather than the shaft, drive, gears, etc. If you use a standard key from a hardware store, and your prop has a collision, the damage to the drive system can be very expensive if the key does not shear.

(rochodl) · (rochodl) **Join Date: Sep 2006** 05-30-2007, 5:03 AM

Hey guys,

Thanks so much for taking the time to provide me with some insight. I am going to check these things out today. 90 and sunny in Michigan today so I want to get out on the lake and board a little.