Long story, but if you have an issue with your driveline Vibrating Rattling or Chattering maybe this will help you resolve your issue. I'm going to give all the facts as I can remember them so that you will see how important it is to do this right the first time. It's a little tedious and the books won't tell you this but it's worth the effort....
I bought this Boat new in 1995. It's a 18' Four Winns Freedom with a 4.3 GM Vortec V-6 with an OMC Cobra Outdrive. This boat ran as smooth as silk for the first few weeks of use. It soon developed an annoying chatter near the rear of the engine. The dealer accused me of running it with the outdrive in the up position and stated that I ruined the u-joints in doing so. As a result it would not be covered under warranty. So I paid them to repair it. The problem still persisted. Long story short I tried several dealers, none of which had the correct solution. Many repairs and thousands in repair bills nobody was able to correct this annoying Noise / Vibration. I even involved the Factory reps and they blew me off accusing me of abusing the boat.
I was the sole driver and know for a fact it wasn't caused by abuse or damage. I knew in my mind that when this boat was new it DID NOT exhibit these problems and that there was a solution. Something had happened and I just had to find what it was.
Well, ten years later and finally letting it get to the point where it was getting really bad I finally set out to resolve the issue myself. ( I know Ten Years??!! save the funny comments for later as my wife had her fun with that already....Better late than never
)
The symptoms were Loud Chattering while idling in neutral. Louder as the engine speed increased. Or as soon as you turn the wheel to the left it would rattle like hell. The sharper the turn the louder it got. It would vibrate some too. Funny.... While turning to the right it would do the same but not as bad. About half as loud, while cruising a straight line and on plane it was as smooth no vibrations but you could hear it rattling. If you tilted the outdrive up towards the top of it's working range it would be worse, down was better but not entirely gone.
After removing the outdrive and replacing the U-Joints I couldn't get the outdrive to seat back into position... I was about one inch short of seating the unit. I wresteled with it for a couple of days on and off....
This is what brought me to the realization that something was indeed wrong with the alignment. Some thing the mechanics told me was dead on..
Turns out the engine alignment was the root cause of all the problems and I will tell you what to do to fix it that the manuals do not tell you. I have not seen this in print anywhere and I have spent awhile searching for a solution.
First, you have to remember that the engine is mounted to Wood and Fiberglass stringers. The motor mounts will settle and NOT evenly.... The power and torque from the engine is always working in one direction pulling up on one side and pushing down on the other....( Down on Port and Up on Starboard) In my case the Port side of the engine was setting down further than the Starboard side. I discovered this by taking multiple measurements from the stringers to a common point on the engine mounts. I was also able to verify the tilt by setting the boat up on the trailer and leveling the transom out. Then placing a level across the valve covers. It was settled down by a quarter inch. Apparently the front of the engine was tilting downwards more on one side than the other..
I haven't made any adjustment just yet. I just wanted to confirm the original postion of the engine. I don't believe anyone of the mechanics had ever adjusted the mounts because the factory paint was still on the threads when I tried to loosen them. ( Tells you something about those mechanics doesn't it?).
I then purchased an alignment tool. It's well worth the investment. At the least borrow one if you have to. ( Note: that the Gimbal Bearing SWIVELS and the tool can be inserted 1/2 way and swiveled until it seats into the coupler.) I installed the tool and it didn't want to go into the coupler at all. I spread some grease on it and installed it again. Then when removing it you can see where the disturbed grease ends. I was falling short of seating the end by about 1/2 inch. This is a problem...... When I finished the following adjustments it went ALL the way in completely and effortlessly.
Now, I started by adjusting the engine mounts and leveling it across the valve covers. Then lifting the engine evenly on both engine mounts upwards about 3 turns on the nuts. The alignment tool was binding pretty good now. I worked in 1 turn increments downwards until the tool was sliding in and out easily. Then I continued downwards until it started to bind again. I found that took about 6 turns in total. then I divided that in half and turned them back up 3 turns. Then I rotated the engine and repeated the centering process again. It took a little while but was worth the effort. The tool slides in and out and turns easily. I rotated the engine 90 degrees several times and the result are the same. No binding.
When I installed the outdrive it literally fell into position and was easy to push into place. I tightened the nuts evenly and torqued them to spec. Using a Crisscross pattern.
NOTE: The end results are that my engine mounts are adjusted to different heights. That is.... the Port side is extended higher than the Starboard. I believe it is because the mounting stringer is slightly crushed on on the Starbourd side from the torque of the engine....
That boat runs as quiet as a mouse now and it's as smooth as silk in turns
I hope this info helps some one out there as it has taken me awhile to get this right..
Please feel free to post you comments or ideas as I will enjoy the feedback.
Good luck
Badzook
.....
I bought this Boat new in 1995. It's a 18' Four Winns Freedom with a 4.3 GM Vortec V-6 with an OMC Cobra Outdrive. This boat ran as smooth as silk for the first few weeks of use. It soon developed an annoying chatter near the rear of the engine. The dealer accused me of running it with the outdrive in the up position and stated that I ruined the u-joints in doing so. As a result it would not be covered under warranty. So I paid them to repair it. The problem still persisted. Long story short I tried several dealers, none of which had the correct solution. Many repairs and thousands in repair bills nobody was able to correct this annoying Noise / Vibration. I even involved the Factory reps and they blew me off accusing me of abusing the boat.
I was the sole driver and know for a fact it wasn't caused by abuse or damage. I knew in my mind that when this boat was new it DID NOT exhibit these problems and that there was a solution. Something had happened and I just had to find what it was.
Well, ten years later and finally letting it get to the point where it was getting really bad I finally set out to resolve the issue myself. ( I know Ten Years??!! save the funny comments for later as my wife had her fun with that already....Better late than never
)The symptoms were Loud Chattering while idling in neutral. Louder as the engine speed increased. Or as soon as you turn the wheel to the left it would rattle like hell. The sharper the turn the louder it got. It would vibrate some too. Funny.... While turning to the right it would do the same but not as bad. About half as loud, while cruising a straight line and on plane it was as smooth no vibrations but you could hear it rattling. If you tilted the outdrive up towards the top of it's working range it would be worse, down was better but not entirely gone.
After removing the outdrive and replacing the U-Joints I couldn't get the outdrive to seat back into position... I was about one inch short of seating the unit. I wresteled with it for a couple of days on and off....
This is what brought me to the realization that something was indeed wrong with the alignment. Some thing the mechanics told me was dead on..
Turns out the engine alignment was the root cause of all the problems and I will tell you what to do to fix it that the manuals do not tell you. I have not seen this in print anywhere and I have spent awhile searching for a solution.
First, you have to remember that the engine is mounted to Wood and Fiberglass stringers. The motor mounts will settle and NOT evenly.... The power and torque from the engine is always working in one direction pulling up on one side and pushing down on the other....( Down on Port and Up on Starboard) In my case the Port side of the engine was setting down further than the Starboard side. I discovered this by taking multiple measurements from the stringers to a common point on the engine mounts. I was also able to verify the tilt by setting the boat up on the trailer and leveling the transom out. Then placing a level across the valve covers. It was settled down by a quarter inch. Apparently the front of the engine was tilting downwards more on one side than the other..
I haven't made any adjustment just yet. I just wanted to confirm the original postion of the engine. I don't believe anyone of the mechanics had ever adjusted the mounts because the factory paint was still on the threads when I tried to loosen them. ( Tells you something about those mechanics doesn't it?).
I then purchased an alignment tool. It's well worth the investment. At the least borrow one if you have to. ( Note: that the Gimbal Bearing SWIVELS and the tool can be inserted 1/2 way and swiveled until it seats into the coupler.) I installed the tool and it didn't want to go into the coupler at all. I spread some grease on it and installed it again. Then when removing it you can see where the disturbed grease ends. I was falling short of seating the end by about 1/2 inch. This is a problem...... When I finished the following adjustments it went ALL the way in completely and effortlessly.
Now, I started by adjusting the engine mounts and leveling it across the valve covers. Then lifting the engine evenly on both engine mounts upwards about 3 turns on the nuts. The alignment tool was binding pretty good now. I worked in 1 turn increments downwards until the tool was sliding in and out easily. Then I continued downwards until it started to bind again. I found that took about 6 turns in total. then I divided that in half and turned them back up 3 turns. Then I rotated the engine and repeated the centering process again. It took a little while but was worth the effort. The tool slides in and out and turns easily. I rotated the engine 90 degrees several times and the result are the same. No binding.
When I installed the outdrive it literally fell into position and was easy to push into place. I tightened the nuts evenly and torqued them to spec. Using a Crisscross pattern.
NOTE: The end results are that my engine mounts are adjusted to different heights. That is.... the Port side is extended higher than the Starboard. I believe it is because the mounting stringer is slightly crushed on on the Starbourd side from the torque of the engine....
That boat runs as quiet as a mouse now and it's as smooth as silk in turns
I hope this info helps some one out there as it has taken me awhile to get this right..
Please feel free to post you comments or ideas as I will enjoy the feedback.
Good luck
Badzook
.....
