Volvo Penta Engine Coupler too small for alignment bar?

[mbwtrpolo]

Hello All! Long-time lurker, but this is my first question to the boating experts! I've got a 2006 Four Winns Volvo Penta 5.0 GXi (SX-M1 outdrive). I pulled the outdrive off for the first time because I felt a vibration at the end of last summer. My nephew came over and helped me because he's got a VP 4.3GL with the same SX-M outdrive so he had the alignment bar (he had changed his gimbal bearing out last year).

When we tried to check the alignment of my gimbal bearing and coupler, we tried running the entire range of the engine adjustment bolts, but we could never really get the alignment bar to go into the engine coupler like it does on his boat. We were able to tap the alignment bar before engaging it into the coupler and think we have it aligned, but the bar will only go into the coupler 5/8". We put a light coat of grease on there and could see how far it would go in.

After we pulled the bar out, we used a piece of thin wall metal conduit to just feel the splines, because it feels like the coupler is just too small for the standard alignment bar to fit. We found that there was a small ridge in the splines, like the alignment bar would hit that ridge and not go in any deeper.

Has anyone seen this before? What could cause the coupler splines to be too small and stop the alignment bar from going full-depth?

Thanks in advance!!

 

[jimmbo]

Wrong alignment bar perhaps?

 

[Thalasso]

Merc Volvo and OMC are the same

 

[Thalasso]

Hello All! Long-time lurker, but this is my first question to the boating experts! I've got a 2006 Four Winns Volvo Penta 5.0 GXi (SX-M1 outdrive). I pulled the outdrive off for the first time because I felt a vibration at the end of last summer. My nephew came over and helped me because he's got a VP 4.3GL with the same SX-M outdrive so he had the alignment bar (he had changed his gimbal bearing out last year).

When we tried to check the alignment of my gimbal bearing and coupler, we tried running the entire range of the engine adjustment bolts, but we could never really get the alignment bar to go into the engine coupler like it does on his boat. We were able to tap the alignment bar before engaging it into the coupler and think we have it aligned, but the bar will only go into the coupler 5/8". We put a light coat of grease on there and could see how far it would go in.

After we pulled the bar out, we used a piece of thin wall metal conduit to just feel the splines, because it feels like the coupler is just too small for the standard alignment bar to fit. We found that there was a small ridge in the splines, like the alignment bar would hit that ridge and not go in any deeper.

Has anyone seen this before? What could cause the coupler splines to be too small and stop the alignment bar from going full-depth?

Thanks in advance!!

Maybe this will help you

http://forums.iboats.com/mercruiser-...os-443992.html
https://youtu.be/MYwnK8mjHdw

https://youtu.be/86gUZXZYtWY

 

[BRICH1260]

Can you reach behind the engine and stick a finger inside the coupler to feel for irregularities?

 

[mbwtrpolo]

Maybe this will help you

http://forums.iboats.com/mercruiser-...os-443992.html
https://youtu.be/MYwnK8mjHdw

https://youtu.be/86gUZXZYtWY

Thanks! I watched those again and there's no doubt I am able to get the gimbal bearing to move a little bit in its seat, because when I partially insert the alignment bar and give it a soft whack with the rubber mallet in the opposite direction I want the alignment bar to go so it slides into the coupler, I can definitely tell I've changed the direction of the alignment bar and can get it to go the 5/8" into the coupler. Once its in, I can turn the alignment bar in the coupler (lots of resistance, obviously), but by doing that, I can easily see the depth I've been able to get the bar to go in. We made sure we turned the engine 90 degrees twice, just to see if the coupler was perhaps an issue. No luck, its really the same thing. We tried the plan of orienting the bar with a mark at 12 o'clock and then carefully inserting it and pulling it out to see how the grease marks looked from the splines, but no matter where we adjusted the height of the front of the engine, we could never get the bar to go in more than that 5/8".

Like I mentioned, then I took that piece of EMT (pipe) and could feel a slight shoulder in the coupler itself and could see a small ridge where the alignment bar could make it to, but then go no further. I just can't understand how that engine coupler could be a smaller inside diameter like that! :mad2:

 

[mbwtrpolo]

Can you reach behind the engine and stick a finger inside the coupler to feel for irregularities?

Great question! Really, all I could do was use that piece of EMT to carefully run it along the splines to see if there was something along the splines, but other than that shoulder (ridge), the coupler is clear.

 

[jimmbo]

You didn't by chance put any grease on the end(tip) of the alignment tool? If so, that could be preventing the tool from going in.

 

[Senior B]

I'm very curious how difficult it was to remove your outdrive in the first place. If the drive slid right off then your Alignment was good to begin with. If you had to pry it off then that's another story. Stop messing with the front mounts and get the Gimbal Bearing Aligned with the coupler first, then make the fine adjustments to the front mounts. There are many posts on here that explain how to do this.

 

[bruceb58]

You didn't by chance put any grease on the end(tip) of the alignment tool? If so, that could be preventing the tool from going in.

You are supposed to put grease on the tip of the alignment bar. Grease can not prevent the bar from sliding in since the the bar doesn't have splines. You are also supposed to grease the input shaft when you install the drive.

 

[mbwtrpolo]

I'm very curious how difficult it was to remove your outdrive in the first place. If the drive slid right off then your Alignment was good to begin with. If you had to pry it off then that's another story. Stop messing with the front mounts and get the Gimbal Bearing Aligned with the coupler first, then make the fine adjustments to the front mounts. There are many posts on here that explain how to do this.

It really wasn't too bad. Just unbolted it and had to pull hard while wiggling. Then I borrowed the alignment bar my nephew used on his VP and that's when the trouble started. We tried moving the front up and down but got no change on how far into the coupler the bar would go.

Yesterday we took a fresh look at it, started the front engine mounts at about the bottom of the adjustment travel, and then carefully went up about two turns (sometimes one) at a time to check the alignment. Once the bar felt like it was about right (hitting the lip of the coupler nicely), I followed the directions of whacking the alignment bar while it was partially inserted into the gimbal bearing to line up the gimbal bearing. That worked really well, but then it just won't slide into the coupling more than that 5/8" (I know I've already said that, but I'm just kinda talking out loud as I'm trying to figure it out myself! On my nephews VP boat, which he did change the gimbal bearing on, the alignment bar slides right in and out, with the two fingers being all it takes to do it.

To ensure it wasn't an issue with the grease binding it (it shouldn't, but just in case), we used a little light oil on the end of the bar, but to no avail. When you look inside (I'll try to get pictures later), the splines on the coupler look fine (not pointed or worn out) (the boat has 308 hours on it).

 

[mbwtrpolo]

Here's an idea too that I wanted to get everyone's thoughts on:

If we pulled the gimbal bearing, we would have unimpeded access to the engine coupler to put the alignment bar into the coupler. Let's just suppose we did pull the gimbal bearing and the engine coupler still wouldn't fit the alignment bar, has anyone ever had that happen? If the engine coupler is really too small to fit the bar (though it does fit the driveshaft, we tried putting the outdrive back on mostly to put our minds at ease that at least the shaft would still fit into the coupler).

Is changing the engine coupler a pull-the-engine affair?

 

[jmb23802]

Your issue sounds like what happened with mine. I don't think anyone had greased the coupler splines in years when I pulled my outdrive. Like you, it came out without too much fuss, but I could not get the alignment bar to go in more than about a 1/2 inch. On mine, the coupler grease had dried and hardened on the splines. There wasn't a lot of grease in there but what was there was just enough to impede the alignment bar.

What I did was remove the gimbal bearing and then use a broom handle or other pipe with a smaller diameter than the alignment tool. I would wiggle the pipe around in the coupler and adjust the engine alignment until I had about equal play towards the sides of the gimbal housing when I cocked the pipe up and down and left to right - just so I could get the alignment "roughed-in".

Once I had the alignment roughed-in, I sprayed a bunch of degreaser spray up into the coupler splines and would then work the alignment bar up in there by hand twisting it around, in and out numerous times, then reapply the degreaser spray and repeat with the bar. After a while, I started to get the bar in far enough I felt that I could get a sense of the direction of the splines relative to the gimbal housing. Once I felt like I had a good sense of the spline direction, I lightly thrust the alignment tool into the coupler a few times to help push through the hardened grease. You have to be very careful when you do this as you can mar the top of the splines a little. I got a the bar in a little further when I did this. Then I started putting grease on the alignment bar and thrusting it in there lightly and got the coupler to loosen up where I could get the alignment bar about halfway in or a little better. Once I had the alignment bar halfway in I would hold the bar at about the center of the slop in the bar and lightly tap it with a hammer once or twice then pull it out and put some more grease on the tool and work it around a while. I probably inserted the alignment bar and twisted it around 500 times during this process.

Eventually, I was able to get the alignment bar in all the way with this method. It took me the majority of the day to get it in there but I did and the coupler has worked fine since. Just be very careful about driving the alignment bar in sideways and creating a ridge on the surface of the splines where the bar will not go in any further.

 

[BRICH1260]

Look at the alignment bar and the diameter of the drive shaft. If they are the same the alignment bar should go in. Your gimble may be out of alignment or not perfectly seated. You might as well go ahead and pull the gimble and plan on replacing it while you are in there. Then while out you can attempt to clean out the coupler a little better. Clean and reinstall new gimble, re-set you alignment, good to go for several more years.

 

[bruceb58]

Look at the alignment bar and the diameter of the drive shaft. If they are the same the alignment bar should go in.

Problem is, the drive shaft is splined so it will always be a bigger diameter than the alignment bar. Pretty doubtful the alignment bar is too big.

 

[mbwtrpolo]

Your issue sounds like what happened with mine. I don't think anyone had greased the coupler splines in years when I pulled my outdrive. Like you, it came out without too much fuss, but I could not get the alignment bar to go in more than about a 1/2 inch. On mine, the coupler grease had dried and hardened on the splines. There wasn't a lot of grease in there but what was there was just enough to impede the alignment bar.

What I did was remove the gimbal bearing and then use a broom handle or other pipe with a smaller diameter than the alignment tool. I would wiggle the pipe around in the coupler and adjust the engine alignment until I had about equal play towards the sides of the gimbal housing when I cocked the pipe up and down and left to right - just so I could get the alignment "roughed-in".

Once I had the alignment roughed-in, I sprayed a bunch of degreaser spray up into the coupler splines and would then work the alignment bar up in there by hand twisting it around, in and out numerous times, then reapply the degreaser spray and repeat with the bar. After a while, I started to get the bar in far enough I felt that I could get a sense of the direction of the splines relative to the gimbal housing. Once I felt like I had a good sense of the spline direction, I lightly thrust the alignment tool into the coupler a few times to help push through the hardened grease. You have to be very careful when you do this as you can mar the top of the splines a little. I got a the bar in a little further when I did this. Then I started putting grease on the alignment bar and thrusting it in there lightly and got the coupler to loosen up where I could get the alignment bar about halfway in or a little better. Once I had the alignment bar halfway in I would hold the bar at about the center of the slop in the bar and lightly tap it with a hammer once or twice then pull it out and put some more grease on the tool and work it around a while. I probably inserted the alignment bar and twisted it around 500 times during this process.

Eventually, I was able to get the alignment bar in all the way with this method. It took me the majority of the day to get it in there but I did and the coupler has worked fine since. Just be very careful about driving the alignment bar in sideways and creating a ridge on the surface of the splines where the bar will not go in any further.

We got it! Well, almost totally have it

So after concerted effort, very similar to what jmb23802 went through, we were able to get the coupler cleaned up enough to get the alignment bar to fit! After reading your experience, jmb23802, I laid awake that night thinking that I wanted to take that piece of EMT and see if that shoulder/ridge inside the coupler was actually just 11 year old grease that had hardened and was stopping the bar from going in.

We first slide-hammered the gimbal bearing loose (couldn't get it all the way removed, but pulled out enough that we had a lot more freedom in moving the alignment bar around), and then scrubbed the coupler with a nylon brush and WD-40. Doing that was enough to get the coupler cleaned up enough to get the alignment bar in.

Now our plan is to remove the gimbal bearing entirely (using a gimbal removal tool we have ordered) (and then replace it), and clean the coupler even more using brake cleaner to really clean out the engine coupler.

We were verrrrry happy to finally get the bar all the way in, and it makes total sense what jmb2302 said in that because we were able to get the bar in 5/8", meaning it did fit, it was just so very strange how the bar would not go in farther, and it felt like it was hitting steel (not like it was running into hardened grease, where there would be additional resistance).

I will keep the thread updated as we go! You are all awesome for what you've contributed, because this just seemed so unlikely that the coupler would be too small for the alignment bar to fit in!

 

[jmb23802]

Glad to hear about your success!

Be sure to put spline grease (search spline grease, which is not the same as bearing grease) on the driveshaft splines and the coupler splines when you put the drive back together. Since your coupler is caked up with old grease I wouldn't be afraid of putting too much fresh grease in there.

Going forward, it would be a good idea to pull your drive on a regular basis and refresh the spline grease to keep it from getting that way again - a regimen of fresh grease will also extend the life of the coupler.

Good luck with the new gimbal bearing and engine alignment!