U-joint Hitting ITSELF at full turn

[ttrm007]

I have been getting a pretty low clunking noise when docking at full turn. I had a shift cable bellows go and tore things down and inspected the gimble and u-joint thinking that might be my clunking noise. Both look great.

I very closely inspected everything and found that the u-joint had a few worn spots on it. I thought it must be hitting the housing but after further inspection, realized that when fully turned, the two u-joints are coming in contact with eachother.

What do I do to correct this? What stops the drive from turning at the end of its range? I'm thinking there must be some bump stop type mechanism somewhere that keeps it from going too far?

Should I grind down the spots where it is coming in contact?

Thanks,
Tom

[Tech Support]

It would be pretty odd for the u-joints to hit each other, especially if they didn't before. Any chance you could snap a pic and post it. I would be curious to see the point it is hitting. I know sometimes the h-yoke has a large casting line that can get in the way, but that would have made noise right away.

Tech Support

[ttrm007]

Pics

The first pic shows how the u-joint would look with a hard turn to the left. The two red arrows show the clear signs of hitting. The second pics shows how it would be with a hard turn to the right. The two worn points are touching in pic 2.

[Tech Support]

I've never really looked that closely for a bump stop. I thought they just ended up hitting the transom. If you look in the area of the steering arm inside the engine compartment you will see that the transom is clearanced for the arm to swivel left and right. I have always assumed that it would turn until it hit that, but I am not sure.

Maybe take a look at yours and see if that is where it hits?

Tech Support

[Tech Support]

Thinking about it some more, that damage must have been done from running the engine with the drive trimmed all the way up, or at least past the trim limit. That would explain the markings on the joints.

It shouldn't be hitting when you turn, so I would guess that the u-joints were damaged from being ran too high, and the noise your hearing while turning is slop in the u-joints, and not the joints hitting each other.

Tech Support

[another todd]

Another possible cause for noise

Some drive models, mine was a mercruiser, have a large thick rubber gasket type seal that goes into the gimble housing before installing the outdrive. This gasket can squish out of place (inward) and can hit the u-joint area of the driveshaft when turning, making a loud thumping or smacking noise that corresponds to engine speed. I had a heck of a time finding the problem. A local dealer listened to it and didn't know what it was. After tearing it apart, it was obvious.