Upper Swivel Shaft

[Slice of Life]

For the past two seasons my 92 Bayliner with Alpha one gen II has had a very minor water leak where the control arm comes out connecting to the upper swivel shaft. I?ve read up on the upper swivel shaft corrosion/seal with sloppy steering issue. I considered taking on the JR Marine drill procedure to replace the shaft and repair/replace the gimbal ring, but have put it off. I replaced the bellows myself two seasons ago and feel confident in this job, preparing for the headache ahead of time. I don't feel safe taking it out this season until it gets fixed/replaced due to the loss of steering possibility I'm reading about.

I'm reading that if one has a water leak in the area, that it's a guarantee that the shaft and seal need replaced, and also that the gimbal ring needs replaced or rebuilt at the least. One of the things I'm unsure on are the modified wrenches required. Watching JR Marine's YouTube video you see him using wrenches that are modified. Their vendor that they sell their cover plate kit from also sells the wrenches for $100, seems a bit steep. Possible without them? The swivel shaft itself varies from $75 to $300. I don't plan on having this boat for another 20 years so if an aftermarket part erodes in half that time so be it.

Is it a safe assumption that the gimbal ring needs reconditioned or replaced because of this, or do some get by with just changing the shaft and seal? I haven?t actually tested to see how far the outdrive will move before the steering wheel moves. It will move fairly easily from side to side by pushing it, but it will not move up and down any at all. Boat is exclusively in fresh water only.
Suggestions? Thanks.

 

[stonyloam]

OK, Step by step: Since you are worried about the condition of the ring, you will want to check that first. Turn the helm so the outdrive is straight and grab the back of outdrive an try to move it side to side. If there is SIDE TO SIDE movement ( don't worry about up down) either your ring or steering arm is loose. If there is play, retorque the two gimbal ring clamping screws to 55 ft lb. if that removes all of the play your ring is OK. If not try to determine if the play is in the steering arm or the ring. Once you do that, you can address your leak. You will want to make sure the seals are where the water is leaking, could be the bellows or large rubber ring that seals the end of the outdrive. When you pull the outdrive take a close look at the bellows and rubber gasket. Replacing the swivel shaft seals is a HUGE PITA. One thing you might want to check is if the seals are below the waterline when the boat is sitting in the water. Both seals are above the top of the gimbal ring.

 

[stonyloam]

If it turns out the ring is OK, and the leak is minor, you MIGHT be able to instal a grease fitting, and pump some 2-4-C and stop or slow the leak. BT Doctur has how to thread. http://forums.iboats.com/forum/engin...ng-bravo-alpha

 

[Slice of Life]

The leak only comes in when the boat is moving forward, when the aft is much lower than forward, or if someone is sitting on the back seat that is almost directly above the outdrive. If the boat is level and not really moving, then there is no water that comes in. When this happens the water line goes above the top of the gimbal ring, but when level the water line is below it. Once the boat has stopped and I anchor, the leak stops. I had leaky bellows before and replaced them two seasons ago, pretty sure it's not that.

The sterndrive link actually says not to try to re-torque the bolts as this might snap the gimbal ring. I'm reading some actually have had this happen when trying to re-torque them

 

[stonyloam]

Yeah I read that uhh"............. Stuff too. The Mercruiser manual states that retorquing the clamping screws on a Alpha I and Gen II should be part of the annual maintanance. I retorqued my loose ring about 9 years ago, it removed all of the play, and I retorque every spring. If it never gets loose it will never wear out. Yeah, sounds like the seals. Personally, if the ring is OK, I would try the grease fitting. You are going to want to add one anyway, you got nothing to lose.

 

[Fun Times]

The leak only comes in when the boat is moving forward, when the aft is much lower than forward, or if someone is sitting on the back seat that is almost directly above the outdrive. If the boat is level and not really moving, then there is no water that comes in. When this happens the water line goes above the top of the gimbal ring, but when level the water line is below it. Once the boat has stopped and I anchor, the leak stops.

While it could be the shaft seal, you may also want to be sure it's not any part of the speedometer hose assembly either since you mention the boat leaks while moving.
Can you visually see where the water firsts enters the boat?

The sterndrive link actually says not to try to re-torque the bolts as this might snap the gimbal ring. I'm reading some actually have had this happen when trying to re-torque them http://www.sterndrives.com/steering_play.html

Interesting. They may just be over paranoid as they've either experienced a bad event or they don't want non technical minded owners over torqueing down bolts to much. From what I've personally seen in the past, the bravo U-bolt had snapped in half from being over tightened vs. cracking the ring.

While in some theory the nut's and bolts wouldn't necessarily come loose/back-off as they are nylock nuts, mechanical movement and/or side to side force wear and tear does start to happen over time between the U-bolt and steel shaft which eventually becomes loose due to worn material and/or stretching.

The idea is more of loosen the bolts/nuts, try to re-center the shaft to the U-bolt the best you can and re-tighten the U-bolt to specifications giving you a better chance at visually inspecting everything while you're in there.

Both service manuals for the Bravo and Alpha stern drives mention that this procedure should now be done every 100 hours or once a year whichever occurs first. That info can be found in the 1B - Maintenance section of both designed stern drive Mercruiser service manuals.

Is that short time frame in the service manual overkill to re-torque? Kind of as it's more depended on how much and how hard you use the boat. Alpha drives tend to not wear out as fast or often vs. a bigger, heavier hard running boat that uses a Bravo drive because Alphas are through bolted while the Bravo uses a U-bolt with nylock nuts. Heavy side to side ocean type swells would be considered heavy wear on the components too.
http://www.mercruiserparts.com/bam/subassembly/5625/2686/90
http://www.mercruiserparts.com/bam/subassembly/5701/11210/70

Also the steering lever assembly inside the boat is known to wear out becoming loose causing side to side movement. You may have to tighten the bolt and nut up some to see if it would help any with the steering too.

 

[Slice of Life]

While it could be the shaft seal, you may also want to be sure it's not any part of the speedometer hose assembly either since you mention the boat leaks while moving.
Can you visually see where the water firsts enters the boat?

The water is coming from where the control arm is, where you can see it's a bit dirty where it has been wet. The speedo tube is in a different spot from there so it would be a separate leak I would think.

I'm going to have someone hold the steering wheel while I try to move the outdrive by hand to see the actual amount of play. I do know that the steering wheel will move by a noticeable amount before you get resistance by the outdrive, though that may be a steering cable issue.