Alpha 1 - Replaced bellows, gaskets, still water in drive bellows and shift compartment

Rick Stephens

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Alpha 1 - Replaced bellows, gaskets, still water in drive bellows and shift compartment

I am kind of losing my mind on this.

Short version: found water in bellows during last winterization, replaced the bellows, gimbal bearing, ujoint crosses, seals, and while there, the water pump and sundry other maintenance items - come spring still finding water in the bellows and shift linkage compartment.

Long version. Bought 1990 Mercruiser 3 liter boat last year. Been going through rebuilding and replacing whatever to make it as 100% as I can. Expected stuff like poor bellows. No fuss. I read everything and pull up Chris’s videos when I need a hint. I have owned several different shops and worked on everything from tugboats to cranes to pickups and computers. Mercruisers are fairly straightforward if a bit ’special tool’ needy.

First thing of note, the bell housing and transom are original and have never been in salt water - very pristine. The leg looks like it was bought as a rebuilt replacement and had been in some salt water before rebuild, has some pitting on the cavitation plate and the mating surface to the bell housing is a bit rough. It is smooth operating, quiet, and the pressure tests are all perfection. So I was good with that.

I replaced all the bellows with original Merc parts. Water pump, crosses, new sealed gimbal completed the job along with oil and a mag tip plug for the bottom gearcase. Winterized and parked it. Took it out in the spring for one day, when back in, pulled the leg and it looked dry. All was good.

Next time using it the boat started dying when shifted. Know what that is, pulled the leg to check the shift cable - bad news - water and grease mix in the bellows and shift linkage area again. So cleaned everything and resealed it, replaced the gasket and paid special attention to everything. Took it out, same thing, water. Did that a number of times, every time after a cleanup of the shift cable and a new gasket kit for the leg, after a day or two it starts having shift problems, pull the leg and there’s water.

So last week stuck another new OEM bellows in it. Went through everything I could - inspected all the components at each end where the bellows attaches - the transom gimbal mount and bell housing and leg. Nothing. I would swear on my mothers grave, if she were dead and had one, that the bellows install is perfect. It went on sweet. All new clamps, water passage oring, gasket and square rubber seal. Didn’t replace the exhaust bellows since it plays no part. Take it to the lake, runs absolutely perfect for one day, next day shift death. Pull it part in the campground - water.

This time I silicon the water passage o-ring in, since the face of the leg is rough there, maybe I'm pumping water in. New gasket, run for a day, starts shifting bad - water.

Next, silicon the entire o-ring and gasket faces between leg and bell housing. No difference. Runs perfect till it won’t shift without dying.


I gotta ask for help. Is it possible there is a crack in the upper gear case letting water in? What am I missing? It is just not that complicated putting a bellows on.

Thanks for thoughts.

Rick
 
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Bt Doctur

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are you using contact cement/bellows adhesive on the large rubber ring that is glued in the housing?
 

Rick Stephens

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No cement on the square ring. Just sliding it into the seat before installing leg.

Rick
 

thumpar

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You should be using bellows adhesive. Follow the directions and let it set up before install.
 

Rick Stephens

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I am using bellows adhesive on the bellows, not the internal square o-ring. I have never ever seen an instruction that recommended putting bellows adhesive on an internal part. Besides, that square o-ring does not keep water out of the drive bellows or the lower shift linkage.


Screen Shot 2014-07-25 at 11.56.17 PM.png
 
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How about your shift shaft bushings in the bellhousing? The upper one is also a seal. If it's worn it could let water into the shift cable area. I don't think it would let water into the bellows though. That black round seal would also have to leak by. I also use some bellows adhesive on that large black seal and let it set up before installing the drive. Use to use some grease to hold it place, but sometimes would still move on me.

Here read this thread on the very subject... post #12 shows the instruction from the manual:
http://forums.iboats.com/forum/engi...es/565125-outdrive-glue-in-gasket-and-o-rings

Here is a picture from Fishermark's with the new revised bushings with better seal: shift shaft bushings.jpg
 
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Bt Doctur

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if the ring is loose/ not seating/dis-lodged it will allow water into the bellows. The mercruiser manual states to use bellows adhesive on it.
 

Rick Stephens

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Thanks for the tips and ideas. #6 Manual says diddly about glue. It can't hurt, that's for sure. I will swap out that bushing/seal. I have sat and looked and stuck my fingers and a flashlight in this thing over and over. I dump a couple of gallons of gooey water out of the bilge, coming from the gimbal, each day out. Lot of water for someone who spends most of the day chugging around on the kicker.

Weird thing on the big input shaft ring is it always is in perfect location when I pull the leg. Never seen it out of position. And yet I still get water up top in the bellows. Figured it was pretty much good for nuthin.

Is there a thicker better bellhousing gasket made? I've used entirely OEM. The gearbox side mating surface is pretty rough. I siliconed both sides this last time, and that didn't change anything. The silicon would be good for at least a day.....

Rick
 

Bt Doctur

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UntitledA3_zps90efd0a0.jpg
 

Rick Stephens

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Thanks. I'll do it that way. Never looked in the #14 since I don't have a Gen II. Method is easy enough to apply.

Rick
 

Rick Stephens

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Well, bad news. Looks like I get to spend some hard earned jack at SEI.

I have repaired and replaced everything I could get to. The issues were:

1) Water in the shift pocket

2) Every day on the water, after an hour or so, when shifting in and out of forward the engine dies.


The water leak was reasonably easy, except I never completely got it even when I siliconed the gasket in. I am certain it isn't leaking from gasket, water passage o-ring or shift shaft seal.. I replaced everything including shift shaft seals. Was able to keep the water out of the drive bellows anyway. *I think there's either a crack or corrosion in the water cooling passages to the shift linkage pocket.*

The hardest one was the dying when shifting after an hour on the water. Pop the engine cover and pull the bolts on the lower shift cable and it was like pushing it through rubber. Stiff as hell. I replaced the shift cable a couple months ago with an OEM one. It is cherry. But run for an hour and it is nasty. I never really noticed this when all we did was fish - spent most of the day on the kicker. But now we try to wakeboard up comes this problem and kills the day. I can always get it into gear to get back to the dock by having my kid put the lever in gear while I hold the cutout cam in place and push the lower cable in. Then we can motor back and I use the kicker to get to the dock.

Again today, that cable is stiff as all get out after an hour of the kids wakeboarding. Dying and grinding like crazy when going into gear now. And with the 4 x 15 inch play prop on the boat, you can hear a thrumming I never heard before when at low cruise - 2800-3200 RPM. (gear noise drives me nuts! - short drive, I know)

Pull it out and an hour later I am in my shop with it. Linkage is again smooth as silk in and out of gear. With the motor off, couldn't move it at all while we were in the water without the cutout cam going all the way over. Now it doesn't even wriggle the cam. Slick and perfect - like it always is when cold.

In the shop, pulled the drive and pulled the upper end of the shift cable loose and it is like butter in your mouth. Perfect. Even the intermediate shift shaft is smooth and easy into and out of gears.

No water in the oil. But bad news is lots of filings on the magnetic tip bottom drain.

I think the upper has a water leak or crack, and the lower has a gear problem that won't stand getting warm. And while the transom and bell housing look like brand new install, the outdrive is an obvious rebuild from a boat that spent a lot of time in salt water.

I don't want to repeat the rebuilt stern drive mistake of the previous owner - who fixed his problem by selling some knothead his boat. So I'm thinking it is time for SEI to step in. I did want to ask if the cost for the tooling makes it wildly silly to do it yourself. The list of special tools is mostly seal drivers and alignment tools, but it is a long list - 47 items. That just for the lower gear case. Seems no way to do my own case and gear job and make it pay off when a actual brand new one is <$1500 with a 3 year warranty.

Thanks for the thoughts. I am kinda bummed tonight.
 

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