Vibration after running aground

[Dudders]

Hi Guys,
A few weeks ago I ran over a sandy/mud bank.
After running aground we headed back into open water and noticed a bit of a vibration happening.
The motor injested a bit of mud and sand which caused the motor to overheat a little. We stopped the boat and called the service dept, they said to slowly crawl back to the launching area and bring the boat in to get checked out.
Once they fixed the overheating problem they took the boat for a test run and said it was fine.
We took the boat out a week later and noticed it was still vibrating and there was a grinding sort of noise.
THis happens whether the boat is heading straight or turning. I did notice it was a little different depending on where the drive was (up or down) but only slightly.
I thought it might be the Gimbal bearings but I am not sure.
Could it be something else?
The Prop is a 4 blade Stainless steel Vensura. It "looks" ok, a couple of real tiny nics out of it (but they have been there since I bought the boat).
The whole boat is less than a year old and only done about 45 hours work.
PLEASE HELP ME.............................

[Tech Support]

The vibration might be either a bent prop shaft or a bent propeller. You can remove the propeller and rotate the prop shaft by hand to look for runout. If you do not have a dial indicator you can set a fixed object next to the shaft while rotating it. It should run true within .005".The prop is hard to check without a pitch gage and might have to go to a prop shop for inspection. As for the grinding noise, I would look to see if there is any sign of the hub rubbing the lower unit housing. If you do not see any scuffing the noise could be internal.

Tech Support

[Dudders]

Thanks for that guys, I will get the service dept dudes to check this out.
I appreciate your quick response.:)