Is This a Coupling Failure... Or My Error?
3.0L 4 cyl with Alpha 1 G2 drives, abut 250 hours total, over 9 (short) seasons. Twins.
I took off the port outdrive to do an over-due transom reseal.
The gimbal bearing was smooth, well greased, and no water in bellows, so decided it did not need replacing. I did the rest of the reseal job.
I put the alignment tool through gimbal bearing into the motor, and it slipped in OK. As I was withdrawing it I fumbled and knocked the gimbal bearing out of alignment...banged it with my thigh not hard enough to leave a bruise, but hard enough to knock the gimbal bearing around a bit. No biggie, but the alignment tool would not go back in. The engine crank hadn't been turned so everything was as it had been when the tool had slipped in except the gimbal bearing tilt.
I figured that goof-up out and got the alignment tool to go back in, but tighter than ideal. Grease swiped off the bottom indicating that the front of the engine was high. Strange, because everything in the front engine mount mount is in great shape: no corrosion to speak of, no rotted stringers, no swelling, not even particularly dirty.... And things rarely sag or settle upward.
Next I rotated the crank 180 degrees. Being a four-banger it is takes a bit of fussing to rotate the crank only 90 degrees because the compression of the pistons makes it prefer 0 or 180 deg's naturally. For this step I figured 180 deg was a good place to start. With the crank at 180 the alignment tool was a little stiff to go into the coupler splines, but it went. I then greased the end of the alignment tool to read the grease and tried again. This time the tool barely entered the splines, maybe only ? inch with no banging or serious persuading on my part. However withdrawing it DID take persuasion.
So I set the alignment tool to the point where the nose was away from the splines but still in the coupler's non-splined part and gave the outer end a little smack with my open palm in all four directions to free the gimbal bearing. Then I tried to insert the alignment tool but got even poorer results. The tool only barely entered the splines and then got stuck there even though I did not insert it with any appreciable force. I tried this a couple of times, always with the same results.
Next I put the crank back to the 0 deg position. The tool went back in, but a touch stiff. Not two fingers, but not requiring a gorilla-grip either. The grease swiped off the bottom leaving spline marks on top as before.
Next I lowered the front of the engine a bit (1/4 turn on top engine mount adjusting nut.) Then the alignment tool slipped right in for 0 deg, but was sticking as as before at 180 deg. I lowered front of engine a little more: ? turn total on front mount top nut. Same situation, though it was getting a little stiffer to insert tool at 0 deg.
BTW:
I have serviced the outdrives myself before, though it wasn't until last year that I actually had an alignment tool of my own. I did a water pump in this drive last year and I did use the alignment tool before putting the drive back on the boat, but it is quite possible that the engine was at rest at the 0 degree crank angle and the tool indicated all was well. As I mentioned the engine prefers to come to rest at either 0 deg or 180 deg unless you do some fussy bumping with the starter or take the spark plugs out, so there is a 50-50 chance it was at the 0 deg when I tested it, and that is the position where the tool goes in fairly well, so I may not have taken any particular notice of an alignment issue. I definitely did not test the alignment at other crank angles at that time.
Now for my question:
OK: I figure the coupler must be eccentric. I am thinking that this would indicate either a defective coupler, defective installation of the coupler(not sure if that is even possible,) or a failing coupler.
So the question I have for the experts is this:
Is this the way that these couplers fail? Do they go eccentric before they quit entirely?
Or did I bungle and knock something out of line by my attempts?
Or is it possible the condition is a defective coupler and it has existed that way since the engines were yard-installed about 9 years ago and the yard just split the difference on the alignment? Recall I said the grease indicates that the front of the engine wants to go DOWN now, which suggests it sagged UPward over time... an unusual condition.
Or am I missing something else here?
This is all just for my own edification. I am not looking for any sort of warranty claim or anything. I am just trying to learn.
Thanks to all.
Peter
3.0L 4 cyl with Alpha 1 G2 drives, abut 250 hours total, over 9 (short) seasons. Twins.
I took off the port outdrive to do an over-due transom reseal.
The gimbal bearing was smooth, well greased, and no water in bellows, so decided it did not need replacing. I did the rest of the reseal job.
I put the alignment tool through gimbal bearing into the motor, and it slipped in OK. As I was withdrawing it I fumbled and knocked the gimbal bearing out of alignment...banged it with my thigh not hard enough to leave a bruise, but hard enough to knock the gimbal bearing around a bit. No biggie, but the alignment tool would not go back in. The engine crank hadn't been turned so everything was as it had been when the tool had slipped in except the gimbal bearing tilt.
I figured that goof-up out and got the alignment tool to go back in, but tighter than ideal. Grease swiped off the bottom indicating that the front of the engine was high. Strange, because everything in the front engine mount mount is in great shape: no corrosion to speak of, no rotted stringers, no swelling, not even particularly dirty.... And things rarely sag or settle upward.
Next I rotated the crank 180 degrees. Being a four-banger it is takes a bit of fussing to rotate the crank only 90 degrees because the compression of the pistons makes it prefer 0 or 180 deg's naturally. For this step I figured 180 deg was a good place to start. With the crank at 180 the alignment tool was a little stiff to go into the coupler splines, but it went. I then greased the end of the alignment tool to read the grease and tried again. This time the tool barely entered the splines, maybe only ? inch with no banging or serious persuading on my part. However withdrawing it DID take persuasion.
So I set the alignment tool to the point where the nose was away from the splines but still in the coupler's non-splined part and gave the outer end a little smack with my open palm in all four directions to free the gimbal bearing. Then I tried to insert the alignment tool but got even poorer results. The tool only barely entered the splines and then got stuck there even though I did not insert it with any appreciable force. I tried this a couple of times, always with the same results.
Next I put the crank back to the 0 deg position. The tool went back in, but a touch stiff. Not two fingers, but not requiring a gorilla-grip either. The grease swiped off the bottom leaving spline marks on top as before.
Next I lowered the front of the engine a bit (1/4 turn on top engine mount adjusting nut.) Then the alignment tool slipped right in for 0 deg, but was sticking as as before at 180 deg. I lowered front of engine a little more: ? turn total on front mount top nut. Same situation, though it was getting a little stiffer to insert tool at 0 deg.
BTW:
I have serviced the outdrives myself before, though it wasn't until last year that I actually had an alignment tool of my own. I did a water pump in this drive last year and I did use the alignment tool before putting the drive back on the boat, but it is quite possible that the engine was at rest at the 0 degree crank angle and the tool indicated all was well. As I mentioned the engine prefers to come to rest at either 0 deg or 180 deg unless you do some fussy bumping with the starter or take the spark plugs out, so there is a 50-50 chance it was at the 0 deg when I tested it, and that is the position where the tool goes in fairly well, so I may not have taken any particular notice of an alignment issue. I definitely did not test the alignment at other crank angles at that time.
Now for my question:
OK: I figure the coupler must be eccentric. I am thinking that this would indicate either a defective coupler, defective installation of the coupler(not sure if that is even possible,) or a failing coupler.
So the question I have for the experts is this:
Is this the way that these couplers fail? Do they go eccentric before they quit entirely?
Or did I bungle and knock something out of line by my attempts?
Or is it possible the condition is a defective coupler and it has existed that way since the engines were yard-installed about 9 years ago and the yard just split the difference on the alignment? Recall I said the grease indicates that the front of the engine wants to go DOWN now, which suggests it sagged UPward over time... an unusual condition.
Or am I missing something else here?
This is all just for my own edification. I am not looking for any sort of warranty claim or anything. I am just trying to learn.
Thanks to all.
Peter
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