Reinstaling lower unit

[TampaTom]

I'm new to owning a 97 200 Merc which I took out yesteday and had the overheat warning go off. Just finished replacing the impeller and can not get the lower unit back on the engine (my back is killing me.) I shined a flash light up into the motor and can see a disk that seems to fit over the drive shaft. I can't seem to aling it or get it out. Not seeing this item in the Clymers.<br /><br />Please advise.

 

[BF]

Re: Reinstaling lower unit

Hi,<br /><br />I don't know about that specific motor (I have an older V6), and I don't know how close you are getting it to go together. When I've put my LU back on, its helped to have someone else around who can slowly turn the flywheel (by hand) as I'm trying to fit the driveshaft splines into the matching splines on the powerhead. Some say take the plugs out to make it easier, but I've never bothered, thumbs on flywheel has worked. Slowly move the flywheel a few degrees and then "magically" it slips into place when the spline align (hopefully). It's good to lightly grease the splines on the driveshaft before reassembly, but don't put any grease on the end of the driveshaft, or it'll take up space and you won't get it together (grease doesn't compress well).<br /><br />good luck.<br /><br />Brent

 

[IBrokeMyFreakinNeck]

Re: Reinstaling lower unit

That is what worked for me. I was killing my back trying to get it back on. I called my brother to help and I turned the flywheel while he eased the lower unit back in, and presto!<br /><br />Edit: This was on my 1972 115 Inline 6, but I'm sure it will work with yours.

 

[outboardguy]

Re: Reinstaling lower unit

That's funny I always pull the lower while it is shifted into reverse,that way when I get close to the splines matching up all I got to do is spin the prop the proper direction and poof it's on.

 

[TampaTom]

Re: Reinstaling lower unit

It not just lining up the splines.<br />The shaft is being blocked by this "disk" or tube that is floating between the powerhead and upper midsection fram. The tube,which looks similiar to a drive shaft seal, moves around and blocks the shaft. <br /><br />My manual shows a rubber seal and nylon tube is used on the shaft top of the 275 HP. I wonder if someone put that on (and it came off). Or is it an endcap drive seal from the bottom of the engine.

 

[Hooty]

Re: Reinstaling lower unit

It sounds like you might be trying to fit the drive shaft into the water tube.<br /><br />c/6<br />Hooty

 

[TampaTom]

Re: Reinstaling lower unit

No. Thank you anyway.

 

[outboardguy]

Re: Reinstaling lower unit

Maybe when pulling the lower unit you inadvertantly pulled the main seal out of the bottom of the powerhead.

 

[TampaTom]

Re: Reinstaling lower unit

Outboard, I think you are right. Does that ever happen? It looks like the only way I'll get at this object is pulling the powerhead off.

 

[outboardguy]

Re: Reinstaling lower unit

Personally Iv'e never seen it happen I was just taking a wild guess judging by your description.I know it is a dark plac but could youn possibly try and post some pictures.I would think that if the seal came out that the only way to fix this problem would be to pull the powerhead as you stated.Hopefully someone else with more experience in this area will respond with more info.

 

[TampaTom]

Re: Reinstaling lower unit

Tried to take pictures but not able to get a good shot. The "ring" is actually two rings pressed together about 1/2" tall oil stained metal. I think its shaft seals. The previous owner had the engine rebuilt. I wonder could it be missing the end cap? The engine mounting nuts are too rusted for me to try. I'm taking it to a real mechanic. Plenty of surprizes in this one. I changed the gear oil. I didn't know that Merc specified sea water. I went back to a petrolum based product.