Volvo Penta Vibration

[nrladeere]

I recently acquired a 21' Chris Craft with a 5.0 Volvo and SX cobra outdrive. I am getting a noticable increase in vibration when making tight turns such as when pulling a tube. I have checked the engin alignment adjusted it slightly. The gimble bearing feels silky smooth. U joints are tight and have been lubed. Where do I go from here? I switched props from my SS to the original aluminum and the vbiration was maybe a little more noticable. Both of my props have a few higkies which have been smoothed. Could the props be causing the vibs? Should I have them balanced? Any other suggestions? Thanks

 

[boat doc]

Re: Volvo Penta Vibration

could be a prop problem, could be alignment (by your description, you know how to properly aligne an engine?) could be a bent shaft (do you have a dial indicator?)

 

[SS MAYFLOAT]

Re: Volvo Penta Vibration

I have a Volvo 280 outdrive. It had a vibration in it. The U-joints felt good, not loose to the feel. But my vibration was from the joints afterall. I would have never thought they were bad until I had pulled them out to find the needle bearings had hammered small grooves into the race of the universal itself. Just a thought....SSM

 

[Dunaruna]

Re: Volvo Penta Vibration

I agree with ssm, feeling the u joints isnt always an accurate test. My 280 vibration was caused by worn out damper (coupler) on flywheel, clacking noise when turning. Aldo

 

[nrladeere]

Re: Volvo Penta Vibration

I am having the prop balanced. I will put a dial on the shaft, but it appears true. I may change the U joint, but they only have 250 hours on them, have been well lubed and alignment has been kept close. I will keep looking. Is it normal to have an increase in vibration when making a tight turn at moderate to fast speeds. Could it be prop cavitation?

 

[BadBoy]

Re: Volvo Penta Vibration

I am haveing the same problem with my Volvo penta 280 leg.There is a slight vibration and a small knocking noise when i rev the engine up and let go the gas.Then when the engine idels agian the noise go's away till i rev it up agian and let go the gas.<br />I took the leg of today and the U joints seemed fine.I also checked the center bearing for play and it is good but then i just replayest it about year ago.<br />I guess i will replace the U joints and try it. I replaced the front U joints but not the back one's.They seemed fine but mabey no<br /><br />Also Dunaruna said something about a worn out damper (coupler) on flywheel.Are you talking about the plate with the springs that bolts to the fly wheel with three bolts.Is that called a flex plate.<br />How can i tell if it is bad.<br /><br />Thanks sorry for the long reply but need to get this thing fixed. <br /> <br />BadBoy