Leak into bilge, bellows?

gsbarry

Petty Officer 2nd Class
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Dec 23, 2024
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116
a couple of things that have hung me up when almost all the way in - the orings on the driveshaft- are these greased up, and when I have been doing alignment work one can build up a lot of grease in the coupler and take some effort to squeeze out.

Did you check the alignment i ok? While it doesn't have to be 100% textbook perfect, just that the witness marks of grease are reasonably even around it. My current boat was never able to get full grease on the bottom of it, further adjusting just took it farther away... Still on the original gimbal and coupler at 20 years /450 hrs...

If so I have had to give it a good foot shove or lightly ( by hand with very little force) use a rachet and the nuts to get it on. Shouldn't take any real force, just snugging it down with a calibrated elbow
I think your saying to check if there is too much grease (causing kind of a suction lock), I'll double check that, but it doesn't seem excessive to me. The alignment still doesn't seem perfect to me, and not as good as it was before replacing the bearing. I had to tap the alignment tool into the coupler the last inch or two with a hammer to get it to fully seat (this is mainly why I think that's my problem). I did give the alignment tool a few moderate whacks with a hammer in each direction as well (sides, top/bottom, but more so the bottom as that appears to be the angle that's binding). Once it was fully seated though it spun freely. When I was installing the outdrive, and got stuck the last 3/4", I tried the Mer-Kick method of a few good kicks on the back of the outdrive. This did not get in any further though, and it basically stuck where it was. I actually couldn't get it back off by hand and had use the method of reinstalling the trim rams and a block of wood on top, then raising the trim to pop the drive back off. So, that too seems to indicate to me sort of a friction bind in the coupler/splines (meaning the splines are partially engaged and aligned rotationally, but misaligned longitudinally) due to slight misalignment. Meaning, if it was just stuck on a lip or something it should have come right back out easily, but sticking in place i can picture the driveshaft may be getting jammed that last 3/4". I'm pretty leery of using the nuts/bolts to suck it in, in my experience with transmissions that's usually a good way to ruin things.
 

Stinnett21

Chief Petty Officer
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Jun 24, 2012
Messages
542
Your picture is puzzling. It appears the upper shift shaft is elevated above the lower. Are you sure you got the two halves mated back together correctly?
 

Lou C

Supreme Mariner
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Nov 10, 2002
Messages
12,965
As far as the issue of the O-rings on the driveshaft, grease can get under the o-rings in that groove and keep them from seating, so when I install those, I clean out the grooves and just lube the orings with bit of motor oil, not grease. Grease goes only on the splines....
For lining up the splines, the Cobra I guess is similar but a bit different than the Alpha, what I do is slide a thin long screwdriver in the ujoint cross area and just slightly turn the driveshaft (these are R+R'd in neutral) and that has gotten it to slip on every time.
 

gsbarry

Petty Officer 2nd Class
Joined
Dec 23, 2024
Messages
116
Your picture is puzzling. It appears the upper shift shaft is elevated above the lower. Are you sure you got the two halves mated back together correctly?
I think that's just the camera angle, can't quite get the phone level with it to take the picture. The shift shaft looks aligned to me.
 

gsbarry

Petty Officer 2nd Class
Joined
Dec 23, 2024
Messages
116
As far as the issue of the O-rings on the driveshaft, grease can get under the o-rings in that groove and keep them from seating, so when I install those, I clean out the grooves and just lube the orings with bit of motor oil, not grease. Grease goes only on the splines....
For lining up the splines, the Cobra I guess is similar but a bit different than the Alpha, what I do is slide a thin long screwdriver in the ujoint cross area and just slightly turn the driveshaft (these are R+R'd in neutral) and that has gotten it to slip on every time.
Thanks, I'll clean up the o-rings and o-ring grooves and apply gear oil only. When the driveshaft is fully seated in the coupler, does the gimbal bearing sit between the 2 smaller o-rings on the driveshaft? or do the o-rings remain astern of the gimbal bearing?
 

Scott06

Admiral
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Apr 20, 2014
Messages
6,666
Thanks, I'll clean up the o-rings and o-ring grooves and apply gear oil only. When the driveshaft is fully seated in the coupler, does the gimbal bearing sit between the 2 smaller o-rings on the driveshaft? or do the o-rings remain aft of the gimbal bearing?
those orings hold the inner race of the gimbal on the driveshaft so they spin together

the single one keeps grease in the coupler for those couplers that have a zerk for the splines
 

gsbarry

Petty Officer 2nd Class
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Dec 23, 2024
Messages
116
those orings hold the inner race of the gimbal on the driveshaft so they spin together

the single one keeps grease in the coupler for those couplers that have a zerk for the splines
thanks, sounds like you're saying the bearing sits between the 2 small o-rings when fully engaged, which makes sense.
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
6,666
As far as the issue of the O-rings on the driveshaft, grease can get under the o-rings in that groove and keep them from seating, so when I install those, I clean out the grooves and just lube the orings with bit of motor oil, not grease. Grease goes only on the splines....
For lining up the splines, the Cobra I guess is similar but a bit different than the Alpha, what I do is slide a thin long screwdriver in the ujoint cross area and just slightly turn the driveshaft (these are R+R'd in neutral) and that has gotten it to slip on every time.
funny you mention cleaning the grooves. on machinery at work when having to reuse an old oring that is compressed... years ago an old timer showed me to put vaseline (food application) or grease in the groove to add some thickness....

Thought he was FOS but it worked
 

Lou C

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Nov 10, 2002
Messages
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Yep I'm not sure where I read that, but it does make sense.
The other thing that really helps the older you get is a drive jack to get the height just right, so much easier on your back!
 

gsbarry

Petty Officer 2nd Class
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Dec 23, 2024
Messages
116
I built a rolling drive stand to the exact height needed for my boat. I have a swim platform so this was essential for me! I make minor height adjustments as needed by adjusting the trailer tongue wheel jack. Anyone know why some pictures show up in-line and others as attachments? I'm uploading them all the same with the "insert image" button. Is it the image size?IMG_8017.jpeg
 
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Lou C

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Cobra drive install.jpgR&R the Cobra.jpg
well worth what I paid for it about 12 years ago
 

Stinnett21

Chief Petty Officer
Joined
Jun 24, 2012
Messages
542
I built a rolling drive stand to the exact height needed for my boat. I have a swim platform so this was essential for me! I make minor height adjustments as needed by adjusting the trailer tongue wheel jack. Anyone know why some pictures show up in-line and others as attachments? I'm uploading them all the same with the "insert image" button. Is it the image size?View attachment 405865
I made one very similar to yours. Helps tremendously, especially at now 65.
 

Stinnett21

Chief Petty Officer
Joined
Jun 24, 2012
Messages
542
I can also vouch for the last 3/4 inch being difficult. What has worked for me is shaking the drive in some way, small quick movements just trying to create some vibration, while pushing inward.
 

cyclops222

Lieutenant Commander
Joined
Mar 21, 2024
Messages
1,839
You have to be VERY STINGY with the grease on the shaft splines. Otherwise the end of the shaft with lots of grease. Can form a BLOCKED OFF trapped air pocket. That will prevent sliding all the way in.
I have seen problems REMOVING splined shafts due to a high VACUUM that built up. I used a hydraulic gear puller then.
 

gsbarry

Petty Officer 2nd Class
Joined
Dec 23, 2024
Messages
116
You have to be VERY STINGY with the grease on the shaft splines. Otherwise the end of the shaft with lots of grease. Can form a BLOCKED OFF trapped air pocket. That will prevent sliding all the way in.
I have seen problems REMOVING splined shafts due to a high VACUUM that built up. I used a hydraulic gear puller then.
If you pump grease into the coupler grease zerk after the outdrive is installed, do you see this causing vacuum as well?
 
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JASinIL2006

Vice Admiral
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Feb 10, 2012
Messages
5,699
If you pump grease into the coupler grease zerk after the outdrive is installed, do you see this causing vacuum as well?
I have not had this problem from using the zerks to grease the coupler or the driveshaft. I have had a dickens of a time getting the driveshaft to seat in the coupler when I got overzealous greasing the driveshaft O-rings. I am very stingy now with that grease and it makes inserting the driveshaft much less troublesome.
 

Lou C

Supreme Mariner
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Nov 10, 2002
Messages
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I have not had this problem from using the zerks to grease the coupler or the driveshaft. I have had a dickens of a time getting the driveshaft to seat in the coupler when I got overzealous greasing the driveshaft O-rings. I am very stingy now with that grease and it makes inserting the driveshaft much less troublesome.
Don’t use grease for those Orings, motor oil only…that’s what it says in my OMC shop manual for the Cobra….
 
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