470 engine alignment

[natemoore]

It looks like the Mercruiser engineers wanted us to do micro-adjustments to the engine alignment by shoving, shaking, and kicking the engine.

I finally got the alignment tool to go all the way in and rotate.

Since there is no specification for maximum pounds of force it should take to fully insert the tool, nor any for maximum inch-pounds of torque is should take to rotate it, one can only guess when the alignment is correct.

So, I can fully insert the tool using only one hand and moderate force, and I can rotate the tool using only my fingertips. I know "moderate" is a completely subjective term, but does this sound about right? I can't imagine getting it any better with the crudeness of the adjusting mechanisms.

Thanks.

 

[ErieRon]

Re: 470 engine alignment

I just read a thread that said the tool should slide in easily and bottom out on the shoulder. It sounded to me like there should not be much resistance when done properly...if any. He even went so far as to stress how critical the procedure is.

Here's the thread; http://forums.iboats.com/showthread.php?t=358106

There is a specific procedure for it, but I can't put my fingers on it right now. If I find it, I'll post it.

 

[natemoore]

Re: 470 engine alignment

I just read a thread that said the tool should slide in easily and bottom out on the shoulder. It sounded to me like there should not be much resistance when done properly...if any. He even went so far as to stress how critical the procedure is.

Here's the thread; http://forums.iboats.com/showthread.php?t=358106

There is a specific procedure for it, but I can't put my fingers on it right now. If I find it, I'll post it.

Thanks for the thread.

I spent the entire day with an inspection mirror and flashlight and my head stuck down behind the engine trying to see which way the engine should go thread the needle, so to speak. It's pretty obvious when you are way off because when you insert the tool you hit a brick wall..or a steel coupler. When you are close enough to insert the tool all the way, but not so absolutely perfect as to make it resistance-free is when the process gets subjective.

I understand in principle what needs to be accomplished. A line is defined by two points, in this case the gimbal bearing and the grease seal. The point is to align the coupler spline co-axially with segment "gimbal bearing-grease seal." But, since you can in fact wiggle the tool around due to the slop in the gimbal bearing and grease seal, you can only hope to get the coupler spline axis inside a cone defined by the aforementioned wobbliture.

Time for another bourbon.

Liked the bit about putting grease on the tool, thrusting it in, then checking out the distribution of the grease. At least that is psuedo-scientific.

 

[Glastron_V210]

Re: 470 engine alignment

I had the same problem after doing a gimbal bearing. Just wouldn't line up when really nothing had changed...or had it...

I realized that it was the gimbal which needed to align to the engine a bit. gimbals can tilt, that's their job. It seems that this is to make our jobs easier, so that the alignment is not a 'get out your micrometer' deal.

I inserted the alignment tool as far as it would go (Took some force), then tapped lightly around it with a hammer. This lines up the gimbal. Then, the insertion was smooth as silk. I fine tuned the alignment with the grease method thereafter.

You want it to insert smooth because when you tilt the outdrive the shaft will slip fore and aft. If it binds your universals pivot and scour you soft aluminum expensive parts.


Try it....little taps.


Chay

 

[bruceb58]

Re: 470 engine alignment

Inspect the splines on the shaft for visible wear, generally if the splines
are worn then the coupler is also worn. If wear is evident replace the parts
as needed.


NEVER Force the alignment tool in, you can damage the tool and the coupler.

NOTE: If you find the tool will not slide into the gimbal simply remove the
black coating on the largest step with fine sand paper.


1) Once you have the engine height close enough to
fully insert the tool without force, then you can start
working on setting the proper alignment.

Take your time, getting it close enough to insert the
tool the first time can sometimes be the hardest (most
frustrating) part.

2) Coat the end section of the tool (the smallest diameter
area) with a light coat of grease and then insert it fully
into the coupler.

3) Without turning the tool, pull it straight out and look at
the depth of the teeth marks in the grease.

If the teeth marks in the grease are deep on the
top side and shallow on the bottom side of the tool then
your motor is too high.

If the marks in the grease are deeper on the bottom than
on the top then your motor is too low.

4) Adjust the engine height accordingly.

5) Keep checking the depth of the marks in the grease until
they are equal in depth on top and bottom.

Sometimes as little as 1/8th of a turn on the adjusting nut can be the
difference between being properly aligned, and just having it "close"

Lightly Grease the splines on the shaft (and on the coupler if you can) with
Spline grease prior to assembly.

 

[EddiePetty]

Re: 470 engine alignment

If the teeth marks in the grease are deep on the
top side and shallow on the bottom side of the tool then
your motor is too high.

If the marks in the grease are deeper on the bottom than
on the top then your motor is too low.

Didn't ya' kinda say that exactly backwards ???

Ed in 'ol Virginny

 

[ErieRon]

Re: 470 engine alignment

Thanks for posting the procedure Bruce. That's the one I was thinking of.

 

[Bondo]

Re: 470 engine alignment

Didn't ya' kinda say that exactly backwards ???

Ayuh,... You're adjusting the Front mount,... Bruce is Exactly Right....

 

[JustJason]

Re: 470 engine alignment

as far as force goes its a by feel thing. If properly aligned, using the gimbal bearing to support the tool, you should be able to slide the tool in and out of the coupler with 2 fingers and a thumb.

 

[natemoore]

Re: 470 engine alignment

as far as force goes its a by feel thing. If properly aligned, using the gimbal bearing to support the tool, you should be able to slide the tool in and out of the coupler with 2 fingers and a thumb.

Need to calibrate. How much can you curl?

Seriously, do you mean holding it with the fingertips or a full 2-finger-1-thumb grasp? Big difference there to me.

 

[natemoore]

Re: 470 engine alignment

Inspect the splines on the shaft for visible wear, generally if the splines
are worn then the coupler is also worn. If wear is evident replace the parts
as needed.


NEVER Force the alignment tool in, you can damage the tool and the coupler.

NOTE: If you find the tool will not slide into the gimbal simply remove the
black coating on the largest step with fine sand paper.


1) Once you have the engine height close enough to
fully insert the tool without force, then you can start
working on setting the proper alignment.

Take your time, getting it close enough to insert the
tool the first time can sometimes be the hardest (most
frustrating) part.

2) Coat the end section of the tool (the smallest diameter
area) with a light coat of grease and then insert it fully
into the coupler.

3) Without turning the tool, pull it straight out and look at
the depth of the teeth marks in the grease.

If the teeth marks in the grease are deep on the
top side and shallow on the bottom side of the tool then
your motor is too high.

If the marks in the grease are deeper on the bottom than
on the top then your motor is too low.

4) Adjust the engine height accordingly.

5) Keep checking the depth of the marks in the grease until
they are equal in depth on top and bottom.

Sometimes as little as 1/8th of a turn on the adjusting nut can be the
difference between being properly aligned, and just having it "close"

Lightly Grease the splines on the shaft (and on the coupler if you can) with
Spline grease prior to assembly.

This is what I've been trying all morning, except when I remove the tool, the spline marks are deeper on the right side, indicating to me that I need to move the engine over to the right (I've been trying to nudge it over all morning) or tap the gimbal bearing to the left as explained by Chay, however I was under the impression that the gimbal bearing could pivot, but not move laterally, or maybe he meant just to adjust the pivot.

I've got my work cut out for me. Not only did I replace the gimbal bearing, but I also had to replace the rotten wood under the front engine mount. Didn't think to make a template for the holes before I cut out the fiberglass and rot. However, I didn't mark and drill the front holes until after I could insert the tool with light/moderate one-handed force.

My adjustment options are, correct me if I'm wrong...

moving the aft end of the engine left or right (due to play in the rear mount),
moving the front mount left or right
moving the front mount up and down

It seems to me that raising or lowering the front mount only pivots the engine about the rear mounts. How do you raise or lower the rear of the engine?

Of course, the manual makes it sound so easy: torque down the rear bolts then move the front of the engine up or down...

Let's see, I'm up to about 700 trips up and down the ladder....

 

[Bondo]

Re: 470 engine alignment

however I was under the impression that the gimbal bearing could pivot, but not move laterally,

Ayuh,... It's a Gimbeled bearing,... It moves just like an Eyeball in it's socket....

moving the aft end of the engine left or right (due to play in the rear mount),
moving the front mount left or right
moving the front mount up and down

Nope,.... #1 is Not an option,... There shouldn't Be any Play.... Only #2,+ #3....

 

[ErieRon]

Re: 470 engine alignment

Nate,

Have you checked your stringers where the mounts are secured? My front one rotted and sagged over the years and caused me to spin my coupler. Might be a good time to check.

Also, I'm pretty sure the manual says to check the alignment at 90 degree intervals of shaft rotation. I assume that means manually rotate the engine via the front nut and check it at 12, 3, 6 & 9:00.

 

[natemoore]

Re: 470 engine alignment

Ayuh,... It's a Gimbeled bearing,... It moves just like an Eyeball in it's socket....


Nope,.... #1 is Not an option,... There shouldn't Be any Play.... Only #2,+ #3....

Good. That explains why I've been kicking/shoving/cussing the aft end with no change in results.

I've torqued it down and am working on the up/down at the front end. I finally got a two-fingertip/thumbtip insertion once, but I pulled it out and tried to immediately reinsert it and had to use a five-fingered full wrap grip to insert.

I seem to be getting spline marks in the grease from about three o'clock to about 7 o'clock if viewing the tool from the rear, which I think calls for lowering the engine, and maybe nudging the front mount to the right.

My brain hurts, but nothing like my leg and butt muscles.....up to 817 trips up/down the ladder.

 

[natemoore]

Re: 470 engine alignment

Nate,

Have you checked your stringers where the mounts are secured? My front one rotted and sagged over the years and caused me to spin my coupler. Might be a good time to check.

Also, I'm pretty sure the manual says to check the alignment at 90 degree intervals of shaft rotation. I assume that means manually rotate the engine via the front nut and check it at 12, 3, 6 & 9:00.

I recently rebuilt the motor and did inspect the coupler. It looks good. I did find rot under the front mount and replaced the factory plywood with PT plywood and re-glassed it. I'm sure having to drill new holes for the front mount is contributing to the challenge.

 

[natemoore]

Re: 470 engine alignment

2) Coat the end section of the tool (the smallest diameter
area) with a light coat of grease and then insert it fully
into the coupler.

3) Without turning the tool, pull it straight out and look at
the depth of the teeth marks in the grease.

If the teeth marks in the grease are deep on the
top side and shallow on the bottom side of the tool then
your motor is too high.

If the marks in the grease are deeper on the bottom than
on the top then your motor is too low.

4) Adjust the engine height accordingly.

5) Keep checking the depth of the marks in the grease until
they are equal in depth on top and bottom.

This is a great technique, but I have a variation.

I applied a very light film of grease on the tool, inserted/withdrew it, and noticed that there were spline marks on bottom & right and none on top & left, which meant to me that the tool wasn't even touching the coupler up top and on the left, which meant I needed to lower the engine and nudge the front to the right.

As I lowered the engine in 1/8 turn increments, I saw that spine marks were working their way toward the top of the tool, then they started getting longer, initially being at the front of the tool, then lengthening toward the rear shoulder.

I got it to where I could insert the tool with two fingers versus the ham fisted thrust I began with. When I rotated the engine 90 degrees, I had to lower it a bit more, but now I've got basically two-fingered insertion through 360 degrees of rotation. I'm calling it done and requesting my engine alignment badge.

Thanks for the help.

 

[ErieRon]

Re: 470 engine alignment

Ah, another job well done !

Congrats.

 

[natemoore]

Re: 470 engine alignment

Ah, another job well done !

Congrats.

Yeah! That was so much fun that I went straight for the bellows replacement/bell housing installation.

Seemed to have misplaced my bullets....let's see, I've got this section of rope....no I think a ball peen hammer is the way I'll end it tonight.