Bayliner 3.0l cobra knocking

[juster121]

First time poster looking for some answers. I own a 1988 bayliner capri with a 3.0L with the cobra outdrive... I was towing the daughter in the tube one day and started to here knocking coming from the back... i stoped the boat and idled the engine and it was smooth. Put in in gear all fine, gave it a little gas and knock knock knock ... I first thought was the engine was going to go.. So limped it back to shore... got it to the dock and put in reverse and floored it and no knock.. put it back in forward and knock knock. Took off the outdrive today and there was water in the bellows so thats not good.. The ujoint look good and the gimbal is a little rough but not bad.. All need to be replaced i am sure.. I am wondering where the knock is comeing from?

 

[Don S]

Re: knocking

Re: knocking

I am wondering where the knock is comeing from?

Probably from the ujoints and gimbal bearing.
If the gimbal bearing is even slightly rough, it needs replaced. I have replaced many ujoints the felt good to me, but when taken apart were pure junk.
Check your outdrive for water too. The input shaft gets rusty and takes out the front seal of the drive.

 

[juster121]

Re: knocking

Re: knocking

Why would it only do it in foward and not reverse... Is there more load or something in foward?

 

[juster121]

Re: knocking

Re: knocking

Probably from the ujoints and gimbal bearing.
If the gimbal bearing is even slightly rough, it needs replaced. I have replaced many ujoints the felt good to me, but when taken apart were pure junk.
Check your outdrive for water too. The input shaft gets rusty and takes out the front seal of the drive.

would a u joint knock in foward and then not hear anything in reverse?