Engine alignment and motor mount question

[CoeGuthrie]

Hello Gentlemen!

First, I would like to thank all of you who contribute to this forum. I have learned alot since I discovered this site about a month ago.

Now on to my question along with a little history:

I live near Colorado Springs, CO, and about a year ago, I was given a '75 Carribean with a Mercruiser 120 and pre-alpha sterndrive. I knew that the thing ran and worked, but that the last time it was out it overheated and needed an impeller change, and hadn't ran in a couple of years. I subsequently replaced the impeller, got it running, and ran it in the driveway with muffs. Ran fine, but long story short- I got water in my outdrive oil and wound up figuring out that I needed a bellows change, gimbal bearing, and a couple of U-joints.:facepalm: Got everything ordered, torn down and ready to go back together. (Thanks to lot's of good info I found here and a factory manual.) In the process of putting it back together and trying to get the alignment right, I found that I have no more adjustment at the front of the motor- in fact, both adjustment nuts are on the threads that are below the mount that is attached to the floor, with the half that is connected to the motor sitting directly on the floor half with absolutely no room to adjust down- and no way to adjust up either. My alignment bar will barely go in, and shows that the front of the motor needs to go down to bring the rear up. To test this, I took one rear motor mount bolt out, lifted the rear of the motor up about a 1/4" and re-inserted my alignment bar. It now goes all the way in, but by the grease tracks I can tell that it still needs to go up a little bit. (The bushing, flat washer, fiber washer, and special lock washer are in place and in the correct order on both rear motor mounts and i can detect no rot in the transom)

So with this information, here are my questions:

• The "special" lockwasher doesn't wear out enough to cause this much sag does it?
• If it doesn't- it looks like there are some type of bushings maybe pressed into the rear motor mount that the rear mount bolt goes through and bushing and washer that the bolt go through first, sit on- do these go bad, and if so, could that be why the rear of my motor seems to be sagging?
• If these bushings do need replaced, are they pressed in, and does the whole motor need to come out to replace them or can I do it in place?
• where is the best place to buy them, and does anyone know a part number?
• am I missing anything?

I sure appreciate any helpful info- as I am a pretty good wrench and carpenter, but boats are new territory to me!

Thanks,
Coe

 

[Don S]

Re: Engine alignment and motor mount question

The "special" lockwasher doesn't wear out enough to cause this much sag does it?

No

If it doesn't- it looks like there are some type of bushings maybe pressed into the rear motor mount that the rear mount bolt goes through and bushing and washer that the bolt go through first, sit on- do these go bad, and if so, could that be why the rear of my motor seems to be sagging?

Yes, and they can cause alignement problems

If these bushings do need replaced, are they pressed in, and does the whole motor need to come out to replace them or can I do it in place?

Yes, the are pressed in, and you need to remove the flywheel cover to replace them.

where is the best place to buy them, and does anyone know a part number?
am I missing anything?

http://www.iboats.com/Rear-Engine-Mount-Sierra/dm/view_id.173150

 

[CoeGuthrie]

Re: Engine alignment and motor mount question

Thanks for the helpful answer Don S.! I'll proceed with that information!

 

[CoeGuthrie]

Re: Engine alignment and motor mount question

Just tonight I finally got the old motor mounts out referenced in this thread. Life has been crazy busy with a lot of changes- for which I have to thank for the delay.

I finally was able to lift the engine up with a hoist and drive the old motor mounts down.(Used a 15/16" socket on the end of a long 1/2" extension to drive them out.)

Only after fighting with it for several hours did I realize that you cannot press them out upwards. DOH!

All this to say- I was disappointed to find out that the old motor mounts were in relatively good shape and are actually taller than the new GLM mounts that I bought, as this was all done in an effort to raise the rear of my engine to get proper alignment. The special washer and fiber washers were all in correct locations also. I also double checked front motor mount location for rot. There is none. Sound as could be.

What am I missing? Any suggestions? All help would be greatly appreciated!

 

[achris]

Re: Engine alignment and motor mount question

The rear mounts can look fine, and still be bad. Did you look at them while they were still under load?

Chris.......

 

[CoeGuthrie]

Re: Engine alignment and motor mount question

You know, I didn't think of that last night... I understand what you are saying and will go ahead and install them and see what difference it makes.

Thanks for the input!

 

[Don S]

Re: Engine alignment and motor mount question

When you install the new rear mounts, make sure you have the spacer installed first and the right way.

 

[Glastron_V210]

Re: Engine alignment and motor mount question

When you install a new gimbal bearing it may press in crooked. If you are sure you have done it right (And you probably did if it didn't get stuck), then your issue likely has nothing to do with the engine mounts.

All of the gimbals I have put in have required an initial 'rough allignment'. In other words, the bearing could be gimballed anywhere when you first install it. If it is pointing in the wrong direction, no amount of moving the mounts will help you get that bar in there.

I'd return the rear mounts, and adjust the front mounts to about 1/2 way.

Insert the bar until it won't go any further. Bump the end at 12, 6, 3, 9 oclock until it will slide in further (Gimbal bearing is moving, alligning with the coupler to allow the bar into the engine coupler). Now that it's engaged, you do your fine tuning with the grease method/mount adjustment. It may take a good bump to get a new gimbal to move...they are pretty tight.

Good luck,

Chay