97 VP Cobra SX Hit Rock - Whining Noise

[happycamper]

We hit a rock at low RPM, which destroyed the prop. I replaced the prop at the lake, and now have a loud whining noise above 1200rpm that's proportional to engine speed. In neutral, there is no noise, even at 3000rpm, which makes me think the lower unit is damaged.

At home, I removed the prop, put on muffs, started the engine, and put it in gear. The whining is coming from the U-joint/gimbal bearing area; not the lower unit.

What's usually damaged on this type of drive when the prop strikes something (besides the prop)?

I have done my own maintenance for 10yrs, including pulling the drive. I think I'll take it to the pros this time, though.
Thanks in advance for your suggestions.

 

[Don S]

Re: 97 VP Cobra SX Hit Rock - Whining Noise

I have done my own maintenance for 10yrs, including pulling the drive. I think I'll take it to the pros this time, though.

I would have a Volvo shop look at it and possibly, you might want to see if your insurance will cover any of this. Whining is not something the SX drives do very often.
There are 3 gears and the shift cone in the upper part of the drive, along with some bearings. I would sure get the drive pulled, the gimbal bearing, ujoints, and uppers gears looked at.
Also have them check the lower prop shaft, could be bent.

 

[happycamper]

Re: 97 VP Cobra SX Hit Rock - Whining Noise

Don,
Thanks for your advice. The loud whining started immediately after the prop strike. Otherwise, the drive has been trouble-free for the 11 years I've owned the boat.

I'll take it to the Volvo dealer, and I'll check with my insurance company.