1981 Sea Ray Sundancer won't shift/running hot. Lower removed

Bill Nelson

Member
Oct 21, 2019
58
New River, AZ
Boat Info
1981 Sea Ray Sundancer
Engines
5.7 L Mercruiser
Got the lower removed on my outdrive. Oh...my...

Good news is that the spline shaft moves freely, and I can shift the lower into gear by hand! So I guess that means it's in the transom shift cable? Removing the upper now.
Last pic is the "naughty bits" (as my British friend would say) that fell out of the lower. Not sure what to think about them.

lower1.jpg
lower2.jpg
lower4.jpg
lower3.jpg
 
Two of the pieces are damaged parts of one shutters that belong at the top of the y pipe,
The other next largest piece looks to be a shaft seal or the centre part of an impeller. It is likely when the impeller parts went through your exhaust system they knocked out the shutter .
 
Two of the pieces are damaged parts of one shutters that belong at the top of the y pipe,
The other next largest piece looks to be a shaft seal or the centre part of an impeller. It is likely when the impeller parts went through your exhaust system they knocked out the shutter .

Ahh, yep that's what it is! I was looking on the wrong parts diagram. It's on the exhaust system drawing!

Somehow, I think I escaped any long lasting damage to the outdrive. Seems unthinkable but it appears to work fine!

Many Thanks, sir! Now I need to pull the Shifter Cable, which is still frozen. ;)
 
Two of the pieces are damaged parts of one shutters that belong at the top of the y pipe,
The other next largest piece looks to be a shaft seal or the centre part of an impeller. It is likely when the impeller parts went through your exhaust system they knocked out the shutter .

I can't figure out how that would mount at the top of the Y-Pipe? Sierra Calls it a Water Shutter, and from the looks of the shape of it, the only place I can see it would mount is where the exhaust pipe meets the gimbal:

baffle.jpg
 
I can't figure out how that would mount at the top of the Y-Pipe? Sierra Calls it a Water Shutter, and from the looks of the shape of it, the only place I can see it would mount is where the exhaust pipe meets the gimbal:

View attachment 76297

You have to go much higher than that.
Up on the motor, there is an elbow on the exhaust that attaches to the top of the Y pipe.

Remove that elbow and you will see the shutter sitting at the top of the Y pipe.
 
You have to go much higher than that.
Up on the motor, there is an elbow on the exhaust that attaches to the top of the Y pipe.

Remove that elbow and you will see the shutter sitting at the top of the Y pipe.

Yep, that's what I thought, but I pulled the elbow and that pipe is 4" in diameter and round not ovular like the baffles. Seems an odd place and would think there would be a gap.?
ypipe1.jpg

Unless it goes below the exhaust elbow, but above the exhaust bellows?

ypipe2.jpg
 

Attachments

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Hmmm.

The newer style y pipe is oval at the top with 2 notches 180° apart for the shaft of the flapper to sit in.

Maybe another look at the parts diagram will help point you in the right direction.
 
What engine do you have? It looks like you have lost both shutters by the junk I see. And what is that growing in the exhaust? Looks like it has been awhile for any maintaince has been done.
 
Last edited:
What engine do you have? It looks like you have lost both shutters by the junk I see. And what is that growing in the exhaust? Looks like it has been awhile for any maintaince has been done.
It's a 5.7 L Merc. I think what is growing in the exhaust is called "neglect"!
 
When I removed the prealpha assembly in our boat, it had a 3 piece Y pipe. Pretty sure the exhaust shutters were located at the bottom in both sides of the center manifold.
 
When I removed the prealpha assembly in our boat, it had a 3 piece Y pipe. Pretty sure the exhaust shutters were located at the bottom in both sides of the center manifold.

Wow, awesome, thanks!! I hate to ask...How do you get them in there? It seems like they are for backing, and when in following seas, yeah? I am wondering if I just take it easy backing, and with not much current in Arizona lakes, if I "need" them?
 
You will need them or theres a chance you can get water up your exhaust when your stopping the water will follow up your rear and hydrolock your engine. Better to fix it now and not kill your motor. Another thing is you have your outdrive apart replace all the bellows, check your gimbel bearing for roughness, replace all the seals in the upper and lower outdrive (both uppers, carrier seals at the prop, shift shaft seal, impeller assembly with inner and outer housing and waterpump hose) not sure if I missed anything but overall rebuild the outdrive. This is not a hard thing to do just buy or make a few tools to to do the job. Then when your done pressure test it to make sure it will hold pressure and no water can get in. I did this on the two outdrives on my Searay 240. Oh also it is easier to mount the halves together while it is off the the boat just make jig out of plywood and a couple of sawhorses to slide the outdrive onto.
 
You will need them or theres a chance you can get water up your exhaust when your stopping the water will follow up your rear and hydrolock your engine. Better to fix it now and not kill your motor. Another thing is you have your outdrive apart replace all the bellows, check your gimbel bearing for roughness, replace all the seals in the upper and lower outdrive (both uppers, carrier seals at the prop, shift shaft seal, impeller assembly with inner and outer housing and waterpump hose) not sure if I missed anything but overall rebuild the outdrive. This is not a hard thing to do just buy or make a few tools to to do the job. Then when your done pressure test it to make sure it will hold pressure and no water can get in. I did this on the two outdrives on my Searay 240. Oh also it is easier to mount the halves together while it is off the the boat just make jig out of plywood and a couple of sawhorses to slide the outdrive onto.

Good advice Lloyd. Just want to nail down exactly where the Water Shutters go on a drawing. I'm an Engineer, so I over-analyze EVERYTHING! ;)
 
You will need them or theres a chance you can get water up your exhaust when your stopping the water will follow up your rear and hydrolock your engine. Better to fix it now and not kill your motor. Another thing is you have your outdrive apart replace all the bellows, check your gimbel bearing for roughness, replace all the seals in the upper and lower outdrive (both uppers, carrier seals at the prop, shift shaft seal, impeller assembly with inner and outer housing and waterpump hose) not sure if I missed anything but overall rebuild the outdrive. This is not a hard thing to do just buy or make a few tools to to do the job. Then when your done pressure test it to make sure it will hold pressure and no water can get in. I did this on the two outdrives on my Searay 240. Oh also it is easier to mount the halves together while it is off the the boat just make jig out of plywood and a couple of sawhorses to slide the outdrive onto.

I think I found it. Crud. I am not at home, but from memory this is going to be a drag to access

exhaust.gif
 
That was not the style mine had. It was 3 pieces. That looks like a 2 piece and maybe for a 4 cyl? I believe the engine has to come out. It is also a good idea to check the mating surface of the Y pipe to transom assembly as well. It is known to be a bad spot for corrosion and can become a boat sinker. Do you have the Mercruiser s/n?
 
I only know all this because of having to rebuild both of my outdrives and removing one of them twice. The only thing I regret not doing is replacing both shift bellows I think one may be leaking.
 
That was not the style mine had. It was 3 pieces. That looks like a 2 piece and maybe for a 4 cyl? I believe the engine has to come out. It is also a good idea to check the mating surface of the Y pipe to transom assembly as well. It is known to be a bad spot for corrosion and can become a boat sinker. Do you have the Mercruiser s/n?

Yeah I may have the wrong drawing. I latched onto the top section looking similar. Bummer.

Merc SN: Is this it?
merc.jpg
 

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