Identifying older model Mercruiser 140 Sterndrive Part

[richyiboats]

Engine year: 1982
Engine Serial #: 6209582
Make: Mercruiser
Type: Sterndrive
Sterndrive Model Number: 1/R Drive
Sterndrive Markings: 6135423 1.98R
Sterndrive Serial #: 6184027

My engine was overheating on my last boating trip (first outing this year). I suspected that the impeller was damaged, so I drained and removed the sterndrive lower unit, and confirmed the impeller was in fact damaged. I am in the process of replacing the impeller, and the upper pump housing. I am also replacing the water pocket cover, as it showed signs of overheating as well. While I was cleaning out the area around the water pocket cover (I was looking up into the upper unit), I felt a loose metal object sitting on the shelf of the upper unit casing, toward the front of the drive shaft. The object was just sitting flat and loose on the shelf. I could not feel any place in the area where it could have fit, nor where it might have been connected to another part. I pulled the object off the shelf. It looks like some kind of shim perhaps, or maybe a part that was dropped into the housing by mistake and left there by a previous owner/repair person (eeek!). It measures 1 3/4 inches across the base at it's widest, and 1 inch at it's tallest. It's about 1/16th of an inch thick, with 5 holes drilled through it. I'll attach a picture of the part, and one of the area of the upper shelf.

The piece was sitting on top of the squared area toward the bottom of the picture.

I need to know what this part is, so I can determine whether I need to remove the upper unit and reinstall the part.
Thanks so much for any help you can give me!

 

[alldodge]

Howdy

That's half of the water shutter also called exhaust flappers. See item 7 in link below
http://www.mercruiserparts.com/bam/subassembly/30891/1058/19

 

[richyiboats]

Thank you! I will take a look.

 

[richyiboats]

Thank you again, AllDodge! I removed the exhaust bellow, and found that most (maybe all) of the exhaust flapper is missing. I will order a new one. I am a bit confused about what I found though, and could use more help. From other pictures and web descriptions of the exhaust flapper, it looked like I would be able to just lift the exhaust flapper from the lower exhaust tube by removing a couple of rubber inserts (one on each side). On mine however, that frame and crossbar are actually riveted to the sides of the lower exhaust tube. I've attached a couple of pictures of the area. Is the crossbar a part of the non-removable frame, on which the exhaust flapper sits? There is just a little side to side play in the crossbar, but it does not really look like it will come out of those riveted brackets. Or, is that crossbar included in the new part, and it's supposed to come out of there?

 

[alldodge]

Your part number is 45586 and the bar is removed. Don't remember if you drill the rivets out (on one side) then reinstall. Well achris or Fun Times knows this better then I maybe he can come in and help.

http://www.mercstuff.com/watershutters.htm

 

[richyiboats]

Thank you! I'll order the part, and hope that achris or Fun Times can confirm whether the rivets have to be drilled out on one side, and the bar pulled in order to install the new exhaust flapper.

 

[Fun Times]

Yes the proper way to replace these design shutters is you'll want to either drill out or you could try chiseling off the rivet heads like mentioned in the OEM service manual and re-rivet. To make it quicker and get more room to work you could carefully try cutting off or bending the old crossbar but first shove a rag down the pipe to stop parts from falling all the way down.

While the second link is of a different design exhaust pipe than yours as the flappers sit lower in the pipe, it helps shows the rivets/brackets to maybe help get some ideas of how to go about this project.

http://forums.iboats.com/forum/engi...305-mercruiser-water-shutter-part-information
http://forums.iboats.com/forum/engi.../466177-how-i-replaced-exhaust-shutter-on-470

 

[richyiboats]

Thank you, Fun Times! This has been very good information, and I believe I can proceed now with confidence. I appreciate both you and AllDodge responding in such a timely manner! Many thanks!

 

[bbook83]

On my 140, I used a Dremel to easily remove the rivets on one side, as there was not room to use a drill. I then replaced the rivets with short stainless screws. A fairly easy fix.

 

[richyiboats]

Great idea, bbook83! Thank you!