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lavoie07
07-03-2009, 05:10 PM
star and stripes 81 with small block
last week i hit a rock or something when i come back the boat vibrate like crazy.
i send the prop to repair, he charge me 100$ to repair it i ask to the guys did you balanced it or something he said no just measured it. i said ok
i put the prop on the boat. Same vibration i can not go 10 mph to much vibration.
i unbolt the cuppler of the shaft and the transmission to check alignement it's ok but i can play with the shaft up and down by the inside of the boat. it's normal or not??? after i screw the shaft to the transmission i start the engine on the trailer just to check if the shaft it's bend, the shaft is bend a little bit at the end but about 1/8, it's ok or not??? i stop the engine and i try to move the prop and the shaft up and down but no loose.
i decide to remove de shaft to straight the shaft but now the coupler at the top he's stuck i try with loose nut, hammer, and steering puller, can i heat this or i have to absoluty cut it.

sorry for my english but i really need help or i scrap it

JimN
07-03-2009, 05:34 PM
star and stripes 81 with small block
last week i hit a rock or something when i come back the boat vibrate like crazy.
i send the prop to repair, he charge me 100$ to repair it i ask to the guys did you balanced it or something he said no just measured it. i said ok
i put the prop on the boat. Same vibration i can not go 10 mph to much vibration.
i unbolt the cuppler of the shaft and the transmission to check alignement it's ok but i can play with the shaft up and down by the inside of the boat. it's normal or not??? after i screw the shaft to the transmission i start the engine on the trailer just to check if the shaft it's bend, the shaft is bend a little bit at the end but about 1/8, it's ok or not??? i stop the engine and i try to move the prop and the shaft up and down but no loose.
i decide to remove de shaft to straight the shaft but now the coupler at the top he's stuck i try with loose nut, hammer, and steering puller, can i heat this or i have to absoluty cut it.

sorry for my english but i really need help or i scrap it

If you can see the bend in the shaft, it needs to be straightened and that's where the vibration is coming from, assuming the prop is balanced. By the way- a prop should be balanced, not just set on a cone to look for which way it tilts. At 4000RPM, any difference will be a lot more noticeable than at lower RPM.

Try using penetrating oil first, but I'm sure someone will add information about removing the shaft. You can heat it but not to an extreme temperature.

lavoie07
07-03-2009, 05:50 PM
thanks for the quick reply
i going right now try to heat with propane

lavoie07
07-03-2009, 08:09 PM
i heat it up but the flange don't want to move tomorrow morning i going to raise de engine and the transmission to pull the shaft out by the other side.

i just want to no if in the brass compling just behind the transmission flange if he have a bushing or something in there i can change.
i'm going to change de strut bushing to.
i just want to change everything because i'm not going to take the engine off every week end.


thanks in advance

XPC Sealman
07-04-2009, 07:25 AM
There is no bushing in the "shaft log". Unless you are running a water cooled shaft seal the bearing would smoke your shaft due to lack of lubrication/cooling. With the shorter shaft lengths on these boats there really is no need for a mid-bearing.