engine alignment how to's

[finer things]

just got my engine alignment tool, here is where I am at ,dropped in engine measured engine mount bolts to put in approximately at same height ,the alignment tool does go in with a little wiggling should it slide in wtih no resistance or should it slide freely thanks for any advice

 

[Alpheus]

Re: engine alignment how to's

Your alignment tool is made up of three precisely sized shafts. The smallest fits exactly into your coupler. The next is sized small enough to pass through your bearing with room to spare, and is long enough to allow the first shaft to engage the coupler 1/2 inch before the larger shaft, sized to exactly fit the gimbal bearing contacts the bearing.

You should feel it bottom out when you slide the bar in. You want the alignment bar to slide in with very little effort and you want spiline marks to be equal all the way around the tip if the bar.

First thing you need to do is make sure your gimbal bearing is set.

Using your alignment bar insert it through the gimbal bearing and just so it starts to go into your coupler. (approx. 1/2 inch)

Using the palm of your hand, give the alignment bar a couple of "whacks" on the top,bottom and both sides of the bar. This will ensure that the gimbal bearing is at the correct angle to your coupler.

Coat the 1st 2 inches of your alignment bar evenly with grease.

Put a mark on your alignment bar near the handle so you can keep your bar in the same orientation when inputting and removing it from the coupler.

Slide the bar into the gimbal bearing and into the splines of the coupler and without twisting the bar pull it out.

You should see spline marks evenly around the end of the bar.

Are the even?

Yes.

Turn the engine over 90 degrees and check again.
Keep turning engine over in 90 deg. increments. This ensures that your coupler is centered and true. Ater the engine has turned 360 degrees go ahead and tighten and torque down the front motor mount top nuts. Check alignment once more just to ensure that the engine has not moved while tightening.

No

Are the spline marks heavy on the top or the bottom?

If they are heavy on the top you need to Lower the front motor mounts half a turn and check again. Keep doing this step until you achieve the results listed above.

Put marks on the motor mount nuts to make sure you turn them both in the same increments.

If the heavy spline marks are on the bottom you need to Raise your front motor mounts half a turn and check again. Keep doing this step until you achieve the results listed above.

Here are some videos to help you along.

This one is showing you when its not aligned. Notice how he uses his hand to smack it in.

http://www.youtube.com/watch?v=fA5ExlPVz2w

This one shows you when everything is just right. Notice how easily the bar slides through the gimbal bearing and into the coupler.

http://www.youtube.com/watch?v=MYwnK8mjHdw

 

[Don S]

Re: engine alignment how to's

An additional note to the above post.
With V8 and V6 engines using side mounts, make sure you have approximately equal weight on each mount. Once you get the alignment where you want it, tighten all the mounts to spec, and RECHECK your alignment. Many times I have seen guys tighten the front side mounts and have the mount pull the engine down and throw the alignment off.

Here are some pictures from the newest Bravo manual that show exactly what Alpheus was explaining. Just remember when using the rubber mallet instead of your hand, the object is to jar the gimbal bearing into place, and you do NOT need to beat the bar with all your strength.

----Videos---
Alignment a little off by Friscoboater

Perfect alignment by Friscoboater

Checking Engine Alignment by Achris

Other useful threads on engine alignment.

http://forums.iboats.com/showthread.php?t=382029

http://forums.iboats.com/showthread.php?t=420900

 

[finer things]

Re: engine alignment how to's

very useful info but when I reinstalled motor mounts I measured there distance and they are different I do know they need to be tweeked but how do I know there is app. equal weight on each one

 

[fat fanny]

Re: engine alignment how to's

What are your grease tracks telling you? If the bar is not sliding in easily and with no resistance you need to follow what the tracks are telling you and start from there as stated by Alpheus in his post once the grease tracks are even the engine is level and in line with drive so it's sitting evenly on the mounts if not the tracks will not be even.

 

[finer things]

Re: engine alignment how to's

I heard to rotate the motor in 90 degree increments when checking the alignment is this necessary and if so how do you do it

 

[Fishermark]

Re: engine alignment how to's

I heard to rotate the motor in 90 degree increments when checking the alignment is this necessary and if so how do you do it

It is a good idea because it checks to make sure your coupler is true and not out of round or off centered.

You simply turn the engine over manually. If you remove the plugs it turns fairly easily. You can generally get a screw driver between the bolt heads on the water pump pulley. It depends on your engine configuration of course.

 

[Alpheus]

Re: engine alignment how to's

I heard to rotate the motor in 90 degree increments when checking the alignment is this necessary and if so how do you do it

Should have read it also. Says it twice in the instructions above...

 

[finer things]

Re: engine alignment how to's

alright I had problems aligning motor followed all instructions to the tee but I could feel the tool hitting the side of the coupler even though I had relatively even spline marks there was a littile resistance going in and out so I thought for the 80 bucks I would bring it to the marina and have it done proffesionnally but he told me coupler was slightly out of round said it should be ok so alright what could I do so came home and rechecked alignment he said he lowered it 1/4 inch I still feel it hitting the coupler a little but now I have deeper marks on bottom of tool everyone has been helpful I think I will realign again and deal with the coupler any ideas would be great thank you

 

[Bluestream]

Re: engine alignment how to's

Normin, seems to have the same problem as you with heavy grease tracks on the side. Consensus was the coupler needed to be "run in" a bit to get it centered.

http://forums.iboats.com/showthread.php?t=445030

Your coupler may have become slightly misaligned from running it with engine out of alignment?

 

[Alpheus]

Re: engine alignment how to's

That post tells me nothing but a bunch of people convincing each other that its OK to run your boat when the alignment is off.

Let me be the first to tell you. Its not OK...




Couplers don't "Run in" Have you ever looked at a coupler? It doesn't move.

If you guys are "running it in" you are taking material off the splines inside the coupler and shortening its life span...

 

[Bluestream]

Re: engine alignment how to's

You are correct the coupler doesn't move, but if you put one in a vise and insert your alignment tool and pull on it, the center splined insert does move as you would expect being in a rubber insert.

 

[Alpheus]

Re: engine alignment how to's

It will move but bounce right back. It wont stay there...

 

[finer things]

Re: engine alignment how to's

alpheus I trust what you say youhave helped me already the marina guy charged me 1 hour to align, I believe he did very little I started again yesterday to align up and down I went I really thought I figured it out the tool was sliding all the way in like butter but when I rotated the motor 90 degrees it was off again I put a piece of tape on harmonic balancer so I have a reference I am going to try again this morning I am going to turn motor over in small increments and try to fine tune otherwise what are my options do I have to remove motor and change coupler

 

[Bluestream]

Re: engine alignment how to's

It will move but bounce right back. It wont stay there...

I believe the theory is that since the center spline on the coupler floats in the rubber insert, if it is out a few thousands of an inch from center that if the engine is aligned and then run for a bit it should center itself up. Other posters have said they will do this, and have done it. I have no first hand experience with this problem, but the theory seems sound.

Obviously if the center spline is "way" out of center on the coupler then this isn't going to work is it.

 

[Don S]

Re: engine alignment how to's

if it is out a few thousands of an inch from center that if the engine is aligned and then run for a bit it should center itself up.

It will NEVER "center itself", the rubber is too hard for that. It will just always be a few thousands off. If the alignment bar goes in and there is a slight drag on removing it, and turn the engine 1/2 turn and it's ok, put the drive on and go boating.