loud vibration noise when in gear with new prop

[craigc0914]

i just had a new prop put on. When i put it in gear, forward or revserse, the prop spins but makes a loud vibration noise. It seems i can turn the prop by hand, but wasnt able to with my last one. When i was at the lake it seemed to not want to get the boat going past 10 mph. This new prop is 13.25 x 16.25 i believe. The last one was the stock one-13.5 x 17.5. I had it put on by a boat dealer, not a nautique dealer. I can rev the engine fine in nuetral. At the lake, it seems as though the prob wasnt spinning as fast as the shaft. Could this be that the prop isnt installed correctly, or wrong size? I got the new prop at a nautique dealer and it came off another nautique.

[NautiqueJeff]

RE: loud vibration noise when in gear with new prop

What year is your boat? What year boat was the prop on? Is there a chance you got one for the incorrect direction of spin?

[craigc0914]

mine is a 2005 SAN. The nautique dealership here said it would work. Not sure exactly what year SAN the prop came off. All i know is that the guys who put it on didnt seem to have the right size key for it, and the diameter and pitch were a tad bit different that the stock one that came off. The new one looks exactly the same as the old one. How can i check what spin it was made for?

[Andrew]

well, wouldn't a right hand prop on a left hand engine go backwards in foward and forward in reverse?

[craigc0914]

yes, its a right side prop. When taking a closer look, there is a round black plastic piece that is loose behind the prop that looks like it fits up in were the shaft comes out to connect to the prop. See pic.

[Andrew]

well, thats definetly not supposed to be there....

i can't tell by the pic, but do u think u maybe need to do a little maintenance on the shaft strut?

[skiinxs]

My guess would be that they didn't have the key in the groove of the prop and shaft properly and it is spinning on the shaft. Pull the prop nut off and look at it from the end. you should see the key engaged in both the prop and shaft. The front of the prop looks like the strut bearing has slid back to the prop. Take it to a dealer who knows what they are doing, obviously the one that did this doesn't have a clue.
Dave

[wake_fun]

Doesn't it seem like the nut is way up the shaft? The cotter pin is going through the end of the shaft and isn't even on the nut.......seems like the wrong nut also.

[bmh2208]

It looks to me like a rope that was wrapped around the shaft and has started to work it's way out. That's exactly what I saw the other day. After I first ran over the rope I got out as much as I could see. A few outings later I noted some more that had worked it's way back down. That nylon heats up and mushes together and looks like some sort of bushing.

[craigc0914]

a rope was caught on the shaft and was cut out while in the lake, after that, it ran fine. The plastic that is housed up in the strut looks like it was chewed away by the rope and is now coming out. Was told i need to purchase a whole new strut, because the material inside the strut is built into the strut. I didnt know a rope could do this much damage to the strut. Is it true i need a new strut if the interior material of the strut is chewed away? Was told if that material isnt there, the high pitch squeeling noise will result. The dealer who put the prop on said they noticed the plastic piece coming out and said my last trip to the lake chewed the rest of the material out with whatever rope was remaining up there. I also noticed the key is not long enough for each end of it to be visible in front of, and behind the prop, and that on the back of the prop, the groove on the shaft is a little off from the groove in the prop. Looks like the key they used wasnt long enough.

[craigc0914]

nevermind on that. I talked to California Correct Craft and they said that material coming out is part of the cutlass bearing and it should still be ok if a little has been eaten up. Strut doesnt need to be replaced. You would think those dumbasses at the moomba/supra dealer i went to would know that. Jesus.

[inboardsonly]

Or it could be a 1-1/8 prop on a 1" shaft...

can you move the shaft up/down or left right more than an 1/8" of an inch?

[craigc0914]

na, its on there tight. It came off a similar SAN.

[tourpro]

The key doesnt need to be the full length of the keyway but you should definately be able to see it. Also the key should barely fit into the keyway on both the prop and the drive shaft with no slop or backlash if you try to turn the prop in either direction.

[boatech]

sounds to me like they left the key way out and it vibrated the sturt bushing out. you dont need a new strut but you should have the bushig replaced. remove strut and send it to a prop shop. have a new bushing put in get a keyway and prop nut stainless steel cotter pin.