Water Leak into U-Joint Bellows, Bellows not Torn?

[ken_23434]

I have a project boat I have been working through the issues on. I had it out on the water about 5 times last fall, sorting out issues each time. This is my first boat, so I am still learning what "normal" is.

I took it out last weekend for the first time this year. I thought there was a strange noise coming from the transom area, but I could not pin point it. It seemed like the noise changed with trim position, but I thought that might have just been in my head. I know that means the u-joints are probably the suspect along with the gimbal bearing.

I checked the bellows externally as best I could, but did not see any evidence of tears etc. I pulled the outdrive off this evening, and sure enough there was some water in the bellows and the u-joints and drive shaft have some rust on them and there is a muddy/milky mess in the bellows.

I wiped out all the junk as best I could and looked / felt around inside the bellows trying to find the "obvious" tear. But, I cannot locate one. The bellows appears to be in very good condition. Not even any evidence of starting to dry out or crack.

I already have a transom service kit on order and have plans to do that whole thing along with new u-joints. My concern is, Is there another way water could have gotten in there?

I am guessing the bellows might not have a good seal at one end, and is leaking that way.

What else should I look for?

Thanks in advance.

 

[boatguya1]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

Did you leave the plug in and have the inside ofthe boat fill with water? There is a vent hole to the bellows that will allow water in from inside the boat.

Other poss is leak at the clamp/clamps or notsealed up well when outdrive installed.

What exactly you are working on would help.

James

 

[ken_23434]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

The boat was in my garage since I last had the outdrive off. So, no issues with rain filling up the boat. That's a good point, though.

I installed the motor the end of last summer. At that time, I replaced the gimbal bearing and installed a new impeller in the outdrive. So, as of the end of last summer, there was no rust issues with the u-joints.

I had the boat in the water a total of about 5 times last fall. Total # of hours in the water only about 10 hours at best. I kept having bad fuel issues I was trying to get through.

I did not mention what engine/drive since it is in my signature...

But, it's an 1988 Mercruiser Alpha 1 behind the 3.0 engine.

 

[Don S]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

It could be the rubber gasket in the bellows got knocked out of place if it wasn't glued in.
a in the drawing below.

 

[ken_23434]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

It could be the rubber gasket in the bellows got knocked out of place if it wasn't glued in.
a in the drawing below.

Does that gasket get glued in place with the PermaSeal stuff, or does it get put in place with the bellows cement?

I do not remember replacing that gasket when I had the outdrive off last summer for the impeller and the gimbal bearing. When I just took it apart, that gasket was there, but it came out easily. It did not take much effort to remove it and I did not pay attention to what position it was in when I took it apart.

Thanks for the advice, Don.

I still plan on replacing all the bellows. I don't know the history of my boat, so I might as well establish some with these parts. Better safe than sorry (or stuck in the middle of the bay).

 

[JustJason]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

You can just use some grease to hold it in place. I always perfectseal the thing into place.

 

[willieboy]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

I had the same issue as you. If it is leaking around the ends, you can usually see evidence on the bellows. Mine was very clear.

 

[87 caravelle]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

i dont believe merc recomended sealing "a" in place. but they did recommend sealing "b" in place.

 

[Don S]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

i dont believe merc recomended sealing "a" in place. but they did recommend sealing "b" in place.

"Merc" doesn't recommend glueing anything in place. However, good common sense does, since either can be knocked out of place easily. a is impossible to see, but by backing the drive out about 1/2" you can see if the water passage oring is in place
All Merc says is (and this is a copy and paste from the manual"

IMPORTANT: Rubber gasket must be properly
positioned in bell housing bore before installing
drive unit, or water may leak into boat.

2. Ensure that rubber gasket and water passage Oring
are properly positioned in bell housing.

 

[JustJason]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

Key word there being "Ensure"

 

[boatguya1]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

I use bellows adhesive on "A", don't care if it is not suggested, it works.

James

 

[stonyloam]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

Had the same muddy milky mess this spring and I know the bellows was good. Turned out to be bad seals (upper and lower) in the outdrive, water was mixing with the outdrive oil and leaking past a bad upper seal into the bellows. Take a look at the outdrive oil, if it is milky you need new seals (maybe more). Good luck.

 

[87 caravelle]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

when would the large o-ring get knock out of position? and has it happend to anyone? im concerned now because i did mine a few weeks ago and basically went step by step with my "merc" manual right there with me. the smaller o-ring i used bellow adhesive but the large one to the ballow i did not. yep....a little worried now.

 

[Fishermark]

Re: Water Leak into U-Joint Bellows, Bellows not Torn?

when would the large o-ring get knock out of position?

It would only happen when installing the outdrive. Personally, I always glue it in place.


To the original poster: How does the area look on the transom side where the bellow attaches? If it has corroded away, it can leak even with a good bellow.