what is too long a time to run a gimble bearing ---

[ab59]

I have been chasing down a few leaks prior to splash time and although i have found most of the problem i still have a dribble that drips down from under the Y pipe but I am thinking it is the driveline bellows. I checked the Y pipe while the engine and outdrive were out of the boat and it looked fine but i did not remove it and replace the gasket and yes i know that was jackass thing to do but it just got by me. Let me say that i have a 350/Cobra sterndrive in my 1988 starcraft that had a 2005 sticker on it as the last time it was used . engine was blown and froze up.
Unless I find a way to examine the bellows without taking the outdrive back out then I plan on changing the bellows and now I am thinking about the bearing as well. I have no way of knowing when the last time these items have been serviced but would a bearing that sat for 13 years need to be replaced of since it had not been used would i even need to worry about it unless it starts making noise ?? I thinks that i already know the answer but wanted some input from those who actually know.
thanks,.

 

[Grub54891]

Replace it. Also the bellows, as 13 years, and leaking will take out the u joints and rust the carrier shaft where it seals the oil in.

 

[Lou C]

Replace the bellows, its not a hard job on the Cobra, I removed the pivot housing and just disconnected the shift cable up on the engine to allow room to pull it back. Make sure to get the rib in the sealing surface lined up on the gimble flange. The gimble bearing if greased and dry will last many years.

 

[Scott Danforth]

with any new to you boat or with waking a boat that has been sleeping.....you do all the maintenance.

that means pulling the drive
servicing the raw water pump
inspecting the gimbal
inspecting the u-joints
changing gear lube
replacing bellows
aligning the drive


going forward, pulling the drive is annual maintenance.

to expand on what Lou stated, with proper mainentance the gimbal bearing would last longer than the boat. lack of maintenance kills boats.

 

[ab59]

i have replaced the raw water pump when i installed the outdrive a few months ago so at least that is done. It looks like the majority popular consensus is replace the bellows and run the bearing so I will order a bellows kit . i had a look at the u-joints at time of installation and they looked fine but i will check them out again since they will be accessible . I did align the drive but with the new wood it sure won't hurt to check again as i did have some settling before.
I have not as of yet changed any of the oils ie gear lubes and had in fact forgotten about them so this would be a great time to take care of that as well. The oil did look clean however and not contaminated .
i keep looking for a good article about changing out a driveline bellows but have not found one yet so if you guys know of a good one for a Cobra i would appreciate it if you would steer me to it.
thanks for all the input guys it sure helps.

 

[Lou C]

With the gimble bearing, turn it by hand with the drive off. It should feel 100% smooth when you turn it. If you feel any roughness then it should be replaced. I have not seen a step by step with pix for the Cobra but there may be one for a Volvo SX; they are nearly the same as far as the bellows replacement. The main difference is disconnecting the shift linkage so you can pull the pivot housing off. On the Volvo you disconnect it on the rear of the upper gear housing; on the Cobra if you don’t want to disturb the shift linkage adjustment you can just disconnect the transom shift cable up on the engine shift bracket (just remove the cotter pin and slide the cable off the mounting pin). This will give you enough slack in the cable to pull back the pivot housing enough to do the job...

 

[Lou C]

Here are some pix of the Cobra bellows, I used OMC gasket sealer on the flange, you orient the bellows clamp between the 1:00 and 2:00 o'clock position on the gimble housing flange, and coat the outer edge of the end that pops into the pivot housing with OMC triple guard grease...

 

[ab59]

i've got the drive out and i can't see a thing wrong with the bellows. i will replace it because of the fact that it is at least 13 years old and could be much older. I see some white crap that does not belong in there as far as i know , would that be an indication of water entering the drive at the mating surface ? i will put up some photos . i have not checked the bearing yet but will after dinner . I can see more white stuff up in back of the bellows , would anything besides water cause grease to turn white ?
Not sure if i need to start another thread as this is turning towards looking for a leak but it will include at least a bellows change and maybe the bearing change as i continue to look for my leak.
If i put a water hose up the exhaust bellows and flood the Y tube would this show if the Y tube is what is leaking ? Any reason NOT to do this ?
At the ramp earlier today i never started the engine and at first i did not see the leak. However after a few minutes the fast dribble started up , probably around a quart or two in 10 minutes.
One last note when i unbolted the drive i just reach over and shook it a little and it came apart easily , does that sound normal ?

 

[ab59]

will try to show the white contamination on the gimble--- left side just under the 2nd bolt . i do think that the spline grease looks like it may have some contamination as well but not as prominent .

 

[kenny nunez]

Just something that will help. The dipstick thread is 1/2” 13 and with a bolt through some chain makes it easier to hold and re-install the drive if you have something to hang it from. As said before if the bearing is smooth it will last. The bearing is the same as the Mercruiser style and the bellows is easier to change than the earlier Mercruiser types. One trick to make the bellows easier to install is to use a 5/16” 1/4” drive universal socket. It is also possible to replace the bellows without removing the pivot housing by removing the wire coil from inside the bellows then feed the coil back in after the bellows is pulled back into the receiver lip and clamped in place. I had the tools to remove the bolts but sometimes the helicoils are somehow damaged and galled to the socket head bolt. I was an OMC dealer for 30+ years so I had a few tricks not found in the service manuals.

 

[ab59]

Kenny Nunez please follow me to -- my new old 1988 starcraft 201v-- I need some OMC Cobra leak advise .please.

 

[kenny nunez]

Plug the bilge drain hole, raise the tongue as high as you can and flood the bilge just below the starter. If nothing shows try shooting the area around the transom shield with a strong stream. That is how I found a leak on my Donzi. Are you sure that the bellows is not split anywhere? It is pretty rare for the “Y” pipe to leak but worth trying.

 

[ab59]

tried the " fill it with water " trick and there is no way to put that much water in there to get it to the waterline and would flood 3/4 of my boat to do so. I am looking for information on removing the gimble pivot now so that i can see behind there and look for any obvious leaks. The drive bellows shows no signs of contamination from water intrusion. There was a puddle in the folds of the bellows but it was oil not water and is why i showed the oil on my fingers in one of the pictures. no water in the oil .
what would be the chances of this being a bad seal between the gimble and transom ? i'm hoping it is a bad fresh water intake hose. Wherever it is coming from it takes a couple of minutes of being in the water to begin to leak and then it is a steady trickle of water.

 

[kenny nunez]

If you get the pivot housing off also look at where the water hose comes through. I have seen on Mercruiser transom plates galvanic action burn holes in the upper areas. Try hitting and stabbing the inner transom to look for soft spots. The transom mounting hardware torques to 12-15 lbs. Try to put a wrench wherever you can and see if any are loose. Sometimes the transom is still good enough to re tighten the bolts after pulling the engine. A transom replacement job around here is around 25-3 k so lets hope you do not need that job.

 

[Lou C]

I took a good look at your bellows pix and I think I see water in there...not a lot but a little, and round the gimble bearing I see some evidence of possible corrosion. The other corrosion you pointed out by the water inlet, is aluminum corrosion, make sure the ground strap is hooked up where it should be.

I had heard that you could do the d/s bellows by removing the exhaust bellows first, I did that and thought that as long as I could get the hinge bolts out of the pivot housing, it was better to remove it because for one, if those never get removed they can seize in place (I was lucky mine came out easily, surprised because this boat has been moored in salt water 6 months out of every season for the past 15 years). Also with the pivot off you can feel better if the rib on the bellows sealing surface is engaged in the groove in the gimble housing flange. I made sure to coat those pivot hinge pins threads with OMC gasket sealer and replaced those fiber washers that go in between the pivot and the transom mount. Not a hard job but fiddly.

I think there was bit of water in your bellows but the u joints and drive shaft look good. Check the gimble carefully. Use an OE bellows they fit and last a long time.

Kenny I wanted to take this opportunity to thank you for your OMC advice and knowledge. It is hard to find! I have a couple of good mechanics who will still work on them but if they retire I'm on my own! I have to say I like the Cobra for a number of reasons and once you learn how to set up the shift cable, they shift well and are not hard to maintain (bellows, impeller easier than on the Merc Alpha).

 

[ab59]

hello Lou C , the stuff you have pointed to in the picture is the oil on my fingers in one of my pictures , i had thought the same thing when i first saw it . i've got both the bellows out now and the pivot loose and am still trying to access the leak and what all parts i will need . i have not been able to find information on the gasket or boot or seal or whatever seals the water between the gimble and the back of the transom . i did find a youtube clip where a guy took a volvo out of a fiberglass boat but did not show any seals. you are sure right about the bearing , it feels rough when turned and i can see both rust and some kind of white corrosion just past the bearing towards the transmission .
Kenny , i got this all apart and am taking a water break ( should be a beer break ) and will go back out and poke around a little more but there is no visible evidence of water coming through anywhere in the gimble. not through the outside anyway.
i took a quick look at the water hose flange behind the gimble at the transom but don't see anything unusual .
i got to say that this restore has been a puzzle all the way and not a lot has come easy. Mostly from my own ignorance .

 

[kpg7121]

tried the " fill it with water " trick and there is no way to put that much water in there to get it to the waterline and would flood 3/4 of my boat to do so. I am looking for information on removing the gimble pivot now so that i can see behind there and look for any obvious leaks. The drive bellows shows no signs of contamination from water intrusion. There was a puddle in the folds of the bellows but it was oil not water and is why i showed the oil on my fingers in one of the pictures. no water in the oil .
what would be the chances of this being a bad seal between the gimble and transom ? i'm hoping it is a bad fresh water intake hose. Wherever it is coming from it takes a couple of minutes of being in the water to begin to leak and then it is a steady trickle of water.

tried the " fill it with water " trick and there is no way to put that much water in there to get it to the waterline and would flood 3/4 of my boat to do so. I am looking for information on removing the gimble pivot now so that i can see behind there and look for any obvious leaks. The drive bellows shows no signs of contamination from water intrusion. There was a puddle in the folds of the bellows but it was oil not water and is why i showed the oil on my fingers in one of the pictures. no water in the oil .
what would be the chances of this being a bad seal between the gimble and transom ? i'm hoping it is a bad fresh water intake hose. Wherever it is coming from it takes a couple of minutes of being in the water to begin to leak and then it is a steady trickle of water.

I have an 87 Starcraft 19 ftr. with transom rot. I had the same issue you have, water in bilge. I found mine because the inside skin had delaminated from the plywood core. I then took core samples & found rot. You can also take a screwdriver with a plastic handle & tap on the outer skin all over the transom. If you hear a hollow soind u have a bad transom. You'll know the diference when you hear it. I'm not trying to rain on your parade but i can tell you that boats of our vintage are prone to rot. That's just the way it is. Hope I'm wrong in your case Good luck.

 

[ab59]

kpg--from the inside of the bilge the transom is solid although it could use some more paint . From the outside lower where the transducers are mounted i had close to 20 old abandon screws to repair and as i did , i took a nail and the end of a rivet depending on how big the hole was and probed the transom . It did not feel soft through any of the holes so i figured that the transom was sound. I have a rubber mallet that i also used to thump on the back of the transom and can't discern much difference anywhere so , i dunno . It also takes about 2 minutes each time before the leak starts almost like something is filling to the leak line before i see the leak so i'm still holding out hope that if it is not the bellows ( and i don't believe it is ) it must be a hose or a hole in the Y pipe further up than the bottom. Tonight i plan on sticking a flashlight up into the exhaust and getting in the boat to see if i can see light coming out from a missed crack or hole . Then i am going to stick the light up to the fresh water inlet and do the same . I of course hope that if there is a hole or crack that i will be able to see the light somewhere in the bilge area.
i figure it this way if worse comes to worse , for now anyway , i will install new bellows and reinstall the outdrive .
In addition , if , when i test the bellows and check for leaks , i still have the leak i am going to silicone the gimble at the transom and sealing it up. If it still leaks then i will know it's not the transom .

 

[Lou C]

hello Lou C , the stuff you have pointed to in the picture is the oil on my fingers in one of my pictures , i had thought the same thing when i first saw it . i've got both the bellows out now and the pivot loose and am still trying to access the leak and what all parts i will need . i have not been able to find information on the gasket or boot or seal or whatever seals the water between the gimble and the back of the transom . i did find a youtube clip where a guy took a volvo out of a fiberglass boat but did not show any seals. you are sure right about the bearing , it feels rough when turned and i can see both rust and some kind of white corrosion just past the bearing towards the transmission .
Kenny , i got this all apart and am taking a water break ( should be a beer break ) and will go back out and poke around a little more but there is no visible evidence of water coming through anywhere in the gimble. not through the outside anyway.
i took a quick look at the water hose flange behind the gimble at the transom but don't see anything unusual .
i got to say that this restore has been a puzzle all the way and not a lot has come easy. Mostly from my own ignorance .

OK what seals the transom mount to the transom is a rope style seal, that fits in a groove that is inside, or on the inner face of the outer transom mount. So when the inner and outer transom plates are installed, this seal gets squeezed into the groove by tightening the 6 nuts that hold the 2 transom plates together with the boat's transom in between. The only way to replace that, is to pull the engine and remove the inner and outer transom plates. Then you might as well check the transom itself, the transom plates for corrosion and the Y pipe for the same. Personally if I went that far, I might start saving up to convert all the old Cobra stuff over to either a late model Volvo SX or Merc Alpha, using used parts.

Lastly if I did this job, what I'd do before installing the engine: install the outdrive and then fab up 2 covers to seal up the Y pipe openings. Then back the boat into the water at a ramp, slowly. Now get in the bilge and look, if there is any leak you will see it now and can address it before installing the engine.

this is one of the reasons why, I would not ever get another outdrive boat. There are just too many places where they can leak water in. In salt water then you can add aluminum corrosion. After this one, only outboards for me.

 

[ab59]

Lou C-- i am slowly coming to the realization that the engine will have to come back out to fix this problem. Hard for me to accept the transom being bad when it appears so solid from the bilge side but it is sure looking like this is most likely what has happened . Even though i have to pull everything apart i don't think that i will be converting this over to an Alpha 1 as i restored this to resell it and have no intentions of keeping it . My plan is and has been to buy and restore then sell a few boats until i get a Starcraft Islander 1988--1994 to keep for myself. This is the second boat in the process and from the way it is turning out i will be lucky just to get my money back out of it . Hard to remember that i only paid 600 bucks for the boat and trailer to begin with.
An odd last couple of years with major illness interrupting the restore that got me derailed and i just kinda lost track of what i was doing.
I guess if i can get out of this one just getting my money back i will be lucky and try to not repeat the mistakes on the next one.