Mercruiser 4.3 Alingment Question

BobMaio

Seaman
Joined
Jan 6, 2011
Messages
54
I recently purchased a 2000 Sea Ray. A new 4.3 was installed by a marina last winter by the previous owner. I am in the process of changing out the bellows, shift cable and other maintenance items and decided to check the alignment. Using the Merc alignment tool, I can only insert this partially. Looks like about 1/2 inch into the splines. When I tested the boat everything seemed fine and the stern drive came off easily enough. I read all the alignment posts so far and I have 2 questions. None of the posts talk about horizontal alignment. That is, all the adjustments are to raise or lower the front of the motor. Why is a side to side adjustment not mentioned? Second question is where do you start with the alignment if I cannot get the tool in enough to see where it is off? I am new to this forum, boating and certainly boating maintenance but I have a lot of automotive maintenance experience. Any help would be greatly appreciated.
 

telstar1

Petty Officer 1st Class
Joined
Jun 20, 2008
Messages
226
Re: Mercruiser 4.3 Alingment Question

get a 2 foot piece of 1 inch bar, insert that in the splines, look which way it is off centre in the gimbal bearing,thatll tell you which way you need to move engine.To do this best,stick the bar into the splines all the way then kind of wiggle the exposed end around to see how much play there is, then hold it in about the average of those extreme positions. This will be the centre, and with proper alignment it will also be centered in the gimbal bearing.This method will get you real close,you can finish up with alignment bar. Dont forget to try the alignment in all 4 quadrants before you start adjusting things, it could be your coupler has a wobble in it. Lots of good info in archives of this forum.
 

Bifflefan

Commander
Joined
May 27, 2009
Messages
2,933
Re: Mercruiser 4.3 Alingment Question

Welcome to iboats.
Look on you-tube for some vids to get the idea of what you are doing.
Start with some wheel bearing grease on the end of the tool that goes in the splines. Then push it in as far as you can (dont jam it), at the end sticking out whack it with the palm of your hand on top (going down) then try to insert it more, if no try the bottom and so on. Repeat as needed. You probably knocked the gimble bearing out of alignment when removing the drive.
Then grease spline marks on top means raise the front, on bottom means lower it.
There is no side to side because that is set when the motor mounts are secured, if its out of alignment side to side you will need to re-drill the mounts.
Like I said, you-tube is a good place to start.
 

BobMaio

Seaman
Joined
Jan 6, 2011
Messages
54
Re: Mercruiser 4.3 Alingment Question

Thanks for the suggestions. I finally got the alignment figured out, but not without a lot of hassle. I first followed telstar1's suggestion about using a pipe. I ended up using 1 inch round woodstock, but it did tell me I was way out of alignment. Then I tried bifflefans suggestion about smacking the tool in each of the quadrants. In my situation, that didn't accomplish anything. I did get confused with which direction to raise or lower the engine based on the threads Don suggested. At one point it says to raise the front if the alignment marks are on top, and others say just the opposite. OK, all that said, this is what I did: I loosened the front motor mount nuts and raised the engine with a come-along attached to the center lifting point. I did this because I wasn't sure if the 2 mounts were set correcty relative to each other. After lifting I ran the bottom adjusting nuts up to be snug with the mount. Then I proceeded to lower the nuts evenly on each side 1 turn at a time. After each turn I would lower the motor onto the mounts and check the alignment. It ended up that the mounts had to be lowered almost a full inch before I got a decent alignment. I never could get the tool to slip in with no effort like I saw in Dons video. It goes in relatively easily but I need to push it in with my palm. Dons video shows it going in with a push of his pinky. Testing the alignment at 90, 180 and 270 told me that the coupler might be bad. At the 180 I have to use a bit more force to push the tool in compared to the 0 degrees. Not bad, but I could feel the difference. As I said in my original post, this unit had the outdive installed. I am confused as to how that would have been possible given the amount of adjustment I had to do to get the alignment tool inserted. Anyone have any thoughts on that?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Mercruiser 4.3 Alingment Question

I ended up using 1 inch round woodstock, but it did tell me I was way out of alignment.

Ayuh,... Are you still using a Stick, or did you get a Real Alignment Bar,..??
 

BobMaio

Seaman
Joined
Jan 6, 2011
Messages
54
Re: Mercruiser 4.3 Alingment Question

The stick was just to see how far off I was without having the gimbal bearing affect the positioning. Once I saw a rough idea of the alignment I used the mercruiser tool.
 

Alpheus

Lieutenant Commander
Joined
Aug 3, 2009
Messages
1,757
Re: Mercruiser 4.3 Alingment Question

Welcome to iboats.
Look on you-tube for some vids to get the idea of what you are doing.
Start with some wheel bearing grease on the end of the tool that goes in the splines. Then push it in as far as you can (dont jam it), at the end sticking out whack it with the palm of your hand on top (going down) then try to insert it more, if no try the bottom and so on. Repeat as needed. You probably knocked the gimble bearing out of alignment when removing the drive.
Then grease spline marks on top means raise the front, on bottom means lower it.
There is no side to side because that is set when the motor mounts are secured, if its out of alignment side to side you will need to re-drill the mounts.
Like I said, you-tube is a good place to start.

That info is 100% wrong. You are one of the people that keep posting the opposite of the correct procedure and it confuses people. I was one of them when I first joined this sight.

The link that Don posted is the only one that you should take your advise from because it is correct...
 
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