4.3 exhaust shutters, what to do/look for when replacing exhaust manifolds and risers

[denhajm]

Hello iboats Members,

I've ordered new Mercruiser exhaust manifolds and risers for my '90 SeaRay 200BR with 4.3L Mercrusier, 2bbl engine. In the mean time, I'm realizing I know very little about the exhaust shutters.

How do I inspect them? What should I be looking for and how do I determine if they should be replaced?

If now is the time to replace the shutters, I'd rather do it when everything is apart.

s/n: 0C861086. Drive s/n: 0D305493.

Thanks!

 

[Rick Stephens]

Really simple. Pull the riser off, then pull the elbow off at the Y-Pipe. The shutters are held in place by a pin under the rubber exhaust hose in the top of the Y-pipe. Be careful here because the parts, and there are several, will drop into your Y-pipe and fall down to the bottom where it is hard to get them out.

The shutter is just a rubber covered flap. It has a stainless pin going through it into holes in the Y-pipe. In those holes are small rubber bushings. So two bushings, one pin and one rubber covered shutter flap. Easy to inspect. I'm missing one of the bushings and mine rattles a bit at certain rpms. I'm going to leave it rattle though :^)

 

[alldodge]

If your Y pipe has never been replaced your new part number is 807166A3, note the A3 ending. Achris explained the change in this thread which is found in the adults only

http://forums.iboats.com/forum/engin...ters-explained

Your parts list
http://www.mercruiserparts.com/bam/subassembly/31478/951/260

 

[denhajm]

Thanks, both of you, for the helpful info! I will grab a flash light and take a look at them.

 

[denhajm]

No Title

Okay, I took a look at what my shutters look like--to me they look just fine. What do you think? I'm planning on leaving them in unless I hear an argument for changing them.

 

[Rick Stephens]

You're golden. Run em for another ten years.

Rick