H20 coming in '86 4.3l OMC cobra

[SteveDavis]

So, first time on the water this year and BAM! Water is coming into my boat. It's not the plug. When I looked under my engine and towards the transom, it appears to have been coming in around there. When I got home, I put on the muffs and gave it a go. With engine off and muffs pumping, everything seemed ok. After I started the engine, I noticed a lot of water being let out, by the bottom of where the outdrive comes through the transom. Seems to be the same place some exhaust is exiting, prior I thought it all came through the prop hub. Anyhow I don't know if they are both related or not, but no water built up in the boat while I had the muffs on. What could be my problem? I need to fix soon, as I have a trip to Rainy Lake planned.

Thanks in advance!
Steve

 

[Anchor Management 1]

Re: H20 coming in '86 4.3l OMC cobra

U-joint bellows or shift cable bellows,The water will come out through the transom ***. and the prop hub it is normal

 

[danond]

Re: H20 coming in '86 4.3l OMC cobra

Water is supposed to exit there. There are "exhaust relief ports" located behind the anode. No biggie.

You haven't found your leak. When was your last bellows replacement? Check the shift cable (the red one) up where it exits the tiny bellows sleeve that seals it inside the engine compartment. All those things are regular service items and need to be checked regularly.

Is your transom rotten?

 

[SteveDavis]

Re: H20 coming in '86 4.3l OMC cobra

I honestly don't know the last time my bellows were replaced. I have owned the boat for 3 years and they have not been replaced by me. My brother in law had it before me, maybe he did it? Don't know, I can check. I don't believe my transom is rotten, but I will check. I am assuming that is easy to figure out.

 

[danond]

Re: H20 coming in '86 4.3l OMC cobra

If you haven't removed your outdrive in 3 years to inspect the bellows, u-joints, and gimbal bearing, now is a good time to do it. There are u-joints in there that need to be greased.

You can also check lower shift cable drag while you're in there. Pull on it with a fish scale while it's disconnected from the carb end - shouldn't require more than 2.5lbs of force. If it's outside the spec, it needs to be replaced (it's easy).

 

[SteveDavis]

Re: H20 coming in '86 4.3l OMC cobra

Should there be a bunch of water coming out by that lower anoide, as shown in my picture?

 

[danond]

Re: H20 coming in '86 4.3l OMC cobra

Yes.

 

[SteveDavis]

Re: H20 coming in '86 4.3l OMC cobra

Thanks, I know it seemed like a dumb question, but even dumber not to ask. I read up on the cooling system, in my OEM manual and it hints around that very point. Well, I was inspecting what I could see on and around my outdrive. And I noticed that one of my bellows looks pretty worn. Could anyone help me figure out what I should have when I pull the outdrive (bellows, sealent, seals, etc.) I am trying to figure it out by looking in my manual, but help from someone(s) who have done it would make me feel more confident that I am doint it correctly.

 

[danond]

Re: H20 coming in '86 4.3l OMC cobra

Trim all the way down/in.

Remove the pin that goes through the outdrive from the end of the trim cylinders (1 nut, pull the pin, trim cylinders will swing down and point at the ground).

Remove the 6 nuts (3 on each side) from the outdrive.

Pull on the outdrive. It will slide out. It's kinda heavy and very clumsy. Have someone help.

Set the outdrive down, and walla - you will be looking at your gimbal bearing, driveshaft bellows, exhaust bellows, driveshaft and u-joints.

Welcome to annual maintenance and inspection

The exhaust bellows will be slotted in the bottom to allow water to drain. Normal.

The driveshaft bellows should be solid. No cracks, holes or dry rot. Replace it if it has those things.

The gimbal bearing should not be rusty, and should turn without any drama by hand. No grinding, no uneven pressure required.

There should be no water or rust in the driveshaft bellows. Replace if there is.

U-joints should not be rusty or loose. Grease them (there is a fitting on each).

The driveshaft splines should be square on top of each, not sharp. Replace the driveshaft if they're worn. Grease the end of the shaft, install 2 new o-rings.

 

[SteveDavis]

Re: H20 coming in '86 4.3l OMC cobra

Well, the help from the great people on this site, my OEM manual, and even the Seloc manual, I should be able to get this done. Tomorrow after work, I plan on finding the parts I need and getting them ordered. One thing I am having trouble locating, is OMC's grease and lubes (mainly the triple guard grease). Anything anyone wants to add, I would appreciate it! Danond, thank you for your patients and help to this point. I really appreciate it. In this day and age, where people seem to think only of themselves, good help is very nice to find. THANKS AGAIN.

 

[danond]

Re: H20 coming in '86 4.3l OMC cobra

You're welcome

You don't need OMC's grease or sealer. I don't think you could find it anyway.

Use Permatex Aviation gasket maker for anything where OMC requests gasket maker/gasket sealer. Use Mercruiser marine grease (get it from a local boat dealer) for their "triple guard grease".

 

[SteveDavis]

Re: H20 coming in '86 4.3l OMC cobra

Ok, ok. I was abl to get my outdrive off by myself, not much to it. I also have both bellows off. Though, I am a bit confused. How can I be seeing water come into my engine compartment, if it is a bellow issue? Yes they are both a little worn, but not to the point of having cracks or holes. Also, my exhaust baffle has no weep ports, for water drain off. Is that a problem? Yet another question. My driveshaft bellow had, what appeaed to be outdrive lube/oil in it. It was acutally pooled up at the bottom of the bellow. Is this normal? If not I must have a seal problem. Lastly, I tested my shift cable for drag. It is out of spec, but it almost seems as if it is due to the metal rod it slides on and some corrosion by the pivot point. I cleaned up the corrosion and it helped a little. I also lubed the metal shaft a little, which also seemed to help. Could I not need a new shift cable?

 

[cr2k]

Re: H20 coming in '86 4.3l OMC cobra

Any lube you use on the shift cable should be very light and thin. Grease or heavy oil will cause drag.

 

[sea wolf]

Re: H20 coming in '86 4.3l OMC cobra

Ok, ok. I was abl to get my outdrive off by myself, not much to it. I also have both bellows off. Though, I am a bit confused. How can I be seeing water come into my engine compartment, if it is a bellow issue? Yes they are both a little worn, but not to the point of having cracks or holes. Also, my exhaust baffle has no weep ports, for water drain off. Is that a problem? Yet another question. My driveshaft bellow had, what appeaed to be outdrive lube/oil in it. It was acutally pooled up at the bottom of the bellow. Is this normal? If not I must have a seal problem. Lastly, I tested my shift cable for drag. It is out of spec, but it almost seems as if it is due to the metal rod it slides on and some corrosion by the pivot point. I cleaned up the corrosion and it helped a little. I also lubed the metal shaft a little, which also seemed to help. Could I not need a new shift cable?

The exhaust bellows should be slotted to relieve back pressure. Are you sure that's not water mixed with oil in the u-joint bellows? I think you should replace both bellows while you have the drive off. It may have a crack in it that you can't see.