New Exhaust Shutters

tpenfield

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Well, i found the backing plates for the exhaust shutters in the exhaust ducts of one of the outdrives when I took them off last fall. So, I am assuming that the shutters are vaporized and should be replaced . . . probably both engines.

It seems that the Mercruiser part is 807166A1 (replaced by 807166A3 ??? Correct ???)

They have the 'A3' on iBoats for a decent price (Mallory brand). Other sources are upwards of $50 each, so it would be $200 for the 'twins'.

I am wondering what the life expectancy is for exhaust shutters, assuming no cooling incidents, or things of that sort ???

There are various brands (Sierra, Mallory, Mercruiser, GLM). . . I am also wondering if there is better/worse experience with certain brands that folks here have tried???

TIA for any advisement on longevity and brand preference. Engines' info in signature below.
 

achris

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Re: New Exhaust Shutters

The last time I had the exhaust elbow off my engine (and it's not a V8, but that shouldn't make too much difference) was a few months ago. The shutters (and the whole engine) are 6 years old, and look in perfect shape. I would expect them to last at least that long again.

As for brand... I would only bother fitting OEM (Quicksilver). I have used a few non-genuine parts in the past, and always come back to genuine... But that's just me. I like my gear to run as perfectly as possible.... :D

You have the correct part number for your shutters (807166A1), the -A3 number is for the older exhaust pipes that had the earlier shutter (single plate with an 'axle shaft') and include an adapter for the top of the pipe. You have the new style pipe.

Chris...........
 

tpenfield

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Re: New Exhaust Shutters

So, the A3 version would not fit in place of the A1 ??? Looks like the A3 versions are more economical . . .
 

tpenfield

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Re: New Exhaust Shutters

I am finding the A3 version for under $30 and the A1 version for about $50 and up.

how come I always end up needing the more expensive version of things ??? :(
 

Don S

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tpenfield

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Re: New Exhaust Shutters

NO, the A3 is not a replacement for the A1, where did you read that it was?
Use the proper OEM part 807166A1 for best results.

Here is the best place to look up OEM part numbers.
https://webapps.brunswick.com/literature/literatureSearch.do

Yes, I got that . . . looks like the "A3" is a modern replacement for the older style shutter, not the "A1".

I probably should open up the exhaust tubes on both engines to see what both sets of shutters look like. I know one of the engine's is completely gone, 'cuz the backing plates ended up in the outdrive. Not sure how the other engine looks though. So, I'll take a look at both engines and order accordingly.
 

Don S

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Re: New Exhaust Shutters

Yes, I got that . . . looks like the "A3" is a modern replacement for the older style shutter, not the "A1".

The 807166A3 shutters were only used on the 3.0 to 4.2L diesels. Not on gas engines at all.


Untitled1.jpg
 

Bondo

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Re: New Exhaust Shutters

Yes, I got that . . . looks like the "A3" is a modern replacement for the older style shutter, not the "A1".

I probably should open up the exhaust tubes on both engines to see what both sets of shutters look like. I know one of the engine's is completely gone, 'cuz the backing plates ended up in the outdrive. Not sure how the other engine looks though. So, I'll take a look at both engines and order accordingly.

Ayuh,... Good plan,.... Ya Gotta put back in exactly what was there....
 

achris

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Re: New Exhaust Shutters

The 807166A3 shutters were only used on the 3.0 to 4.2L diesels. Not on gas engines at all.

Sorry Don, I'm going to call you on that one. The shutter for all V engines from about 1985 to 1995 is -14348A1. Those are the old 'single plate on a shaft' shutters. The new -807166A1 shutters started in 1996, complete with a slightly different Y-pipe. The -14348A1 shutters had a 'falling off' problem, they now superseded to -80766A3, which includes an adapter for the older pipe.

Chris......

attachment.php
 

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achris

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Re: New Exhaust Shutters

I am finding the A3 version for under $30 and the A1 version for about $50 and up.

how come I always end up needing the more expensive version of things ??? :(

I think you'll find the price is for a pair, not each.
 

Don S

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Re: New Exhaust Shutters

Sorry Don, I'm going to call you on that one. The shutter for all V engines from about 1985 to 1995 is -14348A1. Those are the old 'single plate on a shaft' shutters. The new -807166A1 shutters started in 1996, complete with a slightly different Y-pipe. The -14348A1 shutters had a 'falling off' problem, they now superseded to -80766A3, which includes an adapter for the older pipe.

Chris......

Must be my 2009 dealer program. Have noticed a lot of other problems with it too. The other thing, using the OEM site I linked to earlier that has all the latest part numbers does not show the A1 shutters changing to the A3 on the 7.4L that Ted has.

Also note on the Mercruiserparts site you pictured under it's name:

*please note, we are not part of Mercury Marine, but an independent factory authorized Mercury dealer
 

achris

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Re: New Exhaust Shutters

....The other thing, using the OEM site I linked to earlier that has all the latest part numbers does not show the A1 shutters changing to the A3 on the 7.4L that Ted has.

That's right. Mercruiserparts site also doesn't have it changing.

Don S said:
Also note on the Mercruiserparts site you pictured under it's name:

*please note, we are not part of Mercury Marine, but an independent factory authorized Mercury dealer

Yes, I know they are not Mercury Marine, but I haven't found any thing wrong on the parts look-up yet... (Doesn't mean it's 100%, I know, but..... it's pretty damn good)....

Chris....
 

Don S

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Re: New Exhaust Shutters

It just seems those new style shutters are even more restrictive to the 7.4 exhaust that is already minimal with the old style.
 

achris

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Re: New Exhaust Shutters

It just seems those new style shutters are even more restrictive to the 7.4 exhaust that is already minimal with the old style.

I'd never thought of it that way... Maybe a couple of big 4" pipes straight out the back would reduce the back pressure. :D :D :D
 

Don S

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Re: New Exhaust Shutters

I'd never thought of it that way... Maybe a couple of big 4" pipes straight out the back would reduce the back pressure. :D :D :D

Not going crazy the other way either, just saying there is no use restricting the exhaust by another 1/4" on the diameter due to the insert inside the pipe which is about 1/8" thick on each side.
 

tpenfield

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Re: New Exhaust Shutters

Well, when I looked at all the various shutters and part number variations, I knew that I should post a thread to see which part number was the correct one. I do hope that they are priced for the "pair", else it will get a bit pricey.

I would like to go thru-hull with the exhaust at some point, just because I think the thru-the-outdrive passage is a bit restrictive for a 454, as Don mentioned, particularly at the bottom of the 'Y' pipe as it interfaces to the transom assembly.

I'll be checking the shutters this week and then ordering what I need. I found the shutter remnants in only one of the outdrives. Since I don't know much about the maintenance history of the boat prior to purchasing it, I'm not sure if the shutters on the other engine got replaced recently.
 

Don S

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Re: New Exhaust Shutters

Since I don't know much about the maintenance history of the boat prior to purchasing it, I'm not sure if the shutters on the other engine got replaced recently.

Or if they are even there to start with.
 

Bondo

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Re: New Exhaust Shutters

Well, when I looked at all the various shutters and part number variations, I knew that I should post a thread to see which part number was the correct one. I do hope that they are priced for the "pair", else it will get a bit pricey.

I would like to go thru-hull with the exhaust at some point, just because I think the thru-the-outdrive passage is a bit restrictive for a 454, as Don mentioned, particularly at the bottom of the 'Y' pipe as it interfaces to the transom assembly.

I'll be checking the shutters this week and then ordering what I need. I found the shutter remnants in only one of the outdrives. Since I don't know much about the maintenance history of the boat prior to purchasing it, I'm not sure if the shutters on the other engine got replaced recently.

Ayuh,.... If, 'n when ya do, go with Switchable,....

Otherwise, the noise gets really old, really fast....

if my battery hadn't been dead, I coulda shown ya,... ;) LOUD on plane....
 

tpenfield

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Re: New Exhaust Shutters

UPDATE:

I have not opened up the exhaust yet, since the weather has been so cold, I did not want to start the engines until danger of frosts has past. So, here we are, mid-May, and the overnight temps are now in the 40's (F). :rolleyes:

I went ahead and bought the exhaust shutters. I shopped around a bit and got them for $35 Each (rhymes with ouch), @ 4X so about $150 with shipping for the sets for the 'twins'.

I'm still futzing with getting the exhaust tubes apart. It seems the rubber couplers are quite robust in cold weather. So, my plan is to finally run the engines (aka de-winterize/summerize) and hopefully they will be more workable when they are warm.

Any tricks to get the exhaust tubes to come apart from the elbow and/or y-pipe ??? I don't want to take the exhaust elbows off as I have recently installed a full closed cooling system and don't want to break that 'seal'.

So, the plan is to disassemble the exhaust pipes and inspect the shutters, replacing as needed. I did get the remnants (steel plates) of a set of shutters in the outdrive when I took it off last Fall. So, I am assuming that I will need to replace some, if not all of the shutters.

I just want to make sure I am putting the new ones in the correct way.??? . . see photos

The 'top' face of the shutter (I assume . . .)
IMG_2430.jpg

This, I assume is the 'bottom' side ???
IMG_2431.jpg

They would install so that the exhaust would push them open like this heading down into the y-pipe ???
IMG_2432.jpg

So the 'buttons' on the 'bottom' side would touch as the shutter is fully open?

Just want to make sure. :thumb:
 
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