Cobaltchat.com

5.7 Volvo with a DP drive.

New vibration straight out of hibernation. Initial thoughts, U Joints and/or Gimble

Noticed a vibration when leaving the ramp and turning the drive sharp. Felt it in the wheel. No sound other than a grumble from the obvious shake.
Rough water day so hard to determine what else was happening, but by the late afternoon when the lake calmed, I also felt a slight vibration in the floor and wheel while on plane and a straight-line course. Adjusted the rpms to see if it was motor related, no change.

Notes:
Prop is clean, clocked (if that matters) and no dings
Drive fluid was perfect no water intrusion during the lube change
Motor sits and idles quiet and smooth.
Shifts in and out of gear smoothly

Questions in my head:

I'm able to wag the outdrive left and right while the boat is on the trailer. Seems like there was always play for me to do this, but since it has power steering, should I be able to? Just a few degrees either way, not hard down.

Greased the prop shaft, installed the props, torqued to 70ftlbs. When on the trailer, the props spin freely, no drag, no tell-tale sign of binding damage.

Am I on the right track, U Joint / Gimble? Should I be looking at the steering rack as well?

Anything I'm missing?

Thanks

When was the last time you pulled the drive and did an alignment check and just a general look inside the bellows , u-joints and gimbal bearing?

2021, complete reseal of the drive and inspection of the bellows and gimble.

Probably 50 hours on it since. I decided to bite the bullet and schedule a service call just in case. Catch it early before there are too many boats in line at the garage.....

Not sure what they will find, but if its the u joint, I will have them replace the bellows, gimble bearing, and trim sensor while its apart.

Probably should be pulling every other year at least. I typically did it every year with my older boat(Volvo Penta). Been a little more lax with my current Cobalt.

U joint and gimble needs replacing according to the dealer. Had to buy the entire shaft assembly as Volvo wont sell the U joints anymore. Replacing the bellows and trim sensor as well.

$2300 for those about to do the same....

Pilotmike wrote: Fri Jun 14, 2024 4:59 pmHad to buy the entire shaft assembly as Volvo wont sell the U joints anymore.

That's been that way for over 20 years with Volvos. I did a shaft replacement back in 2002 on my previous boat.