I was looking things over yesterday in the bilge and saw that the merc motormount bottom jam nut had backed off considerably, the lock tab was in tack but appears to have deformed enough to let the bottom nut rotate.

Now I've got to find an alignment tool which i can likely borrow from the local shops. 64 hrs on the boat, I was surprised to see this.

I think better motormounts will be a winter project. Anyone have preferences here- 25' Daytona if it makes a difference, 454 mag MPI/ Whipple.

This is one of the things I check when doing maintenance along with steering fastners. Mounts are a little harder to get to. I try and check all critical fastners when doing belts, oil changes etc.

If the top Lock nut is still in place and the nylock is still good it should be in original position. You could tighten the bottom nut up and everything (should) still be alighned. No doupt it is better to check alighnment to be sure but in a pinch it should be OK.

Offshore mounts are cool and strongest but I have seen some pretty high horsepower rigs running with stock mounts with no issues. As long as they are tight! Everyboody has there own preferances though.

I just had my flashlight out and my head in the bilge yesterday checking mine.

After reading this post I thought of something I seen on my re-power. Should these stainless tabs be bent down to hold the bottom nut in place? Did the installer not do it right?

Ray;

Those tabs are supposed to be bent down. They are what lock the bottom nut in place.

One tab bends against one of the six sides of the nut, the other goes in the opposite ditection against one of the flat sides of the mount itself. I'm glad this post may be helping others.

Drew, I had the same thoughts, and that's what I did short term, but being it's the beginning of summer...

Ray,
How in the world did you take that picture????? I know it could not of been easy
Don’t worry about the locking tabs take a small hose clamp and put it under the bottom nut. This is the only fix for that mount and even after that you need to keep checking them.

I'm sorry you guys are having the same problems I did for the last three years If you have to pull the motors plan on changing over to offshore mounts. It is such a hassle tightening the mounts three or four times a year. I actually had a motor fall over on to the stringer because of these

You will be fine just tightening the bottom nut my alignment never changed until the motor incident. Scott

Since my boat has a liner , It would have been a real hassle changing over to an offshore mount.
The factory mounts are thru bolted to and aluminum box that is glassed in , and I hope those boxes where bolted to a stringer, it is impossible to tell unless I start cutting up the liner.
What I ended up doing is having solid mounts made from blocks of aluminum. Those have seem to work so far, no loosening problems.

Scott, I got lucky with the picture. I could not see what was in the bilge. so I stuck my digital camera with flash under there and started snapping pictures. There is some other debris like nuts and flexible tubing I need to fish out too. How I would like to tack-weld a bubble on that stud! I will try the hose clamp thing. BUt the "whipple" side is going to be real tough. Are they easier to get at from the front or would it be easier to flip the sunpad back and give it the reach arround?

Ray,
It will be as tough as it looks you need to go in from the front I did mine with two people and it was still tough.

Hint: Hire a skinny Kid