Exhaust Bellows internal flappers

[Addis]

When changing both exhaust bellows on Aquamatic 280 drives I noticed one of the bellows being replaced looked like it did had have a set of flappers on one end ( which were gone) and the other bellows looked like it never had any and it was never designed for any. My question is - Are these interior flappers necessary on these exhaust bellows?

 

[Watermann]

Exhaust flappers jn any IO set up are needed if you want to limit the chances of the motor ingesting raw water.

 

[Scott Danforth]

volvo AQ280 doesnt have flappers unless you count the one at the vary end of the drive.

 

[bruceb58]

Exhaust flappers jn any IO set up are needed if you want to limit the chances of the motor ingesting raw water.

Those year Volvos didn't have them and Volvos starting in around 2000 don't have them anymore either.

 

[Watermann]

Those year Volvos didn't have them and Volvos starting in around 2000 don't have them anymore either.

Ok great, any IO equipped with flappers should have them if you want to avoid water being ingested into the motor. Is that better?

 

[Addis]

When searching for the original part number another number was given probably because of the age of this model( 1978). After purchasing these replacements the new bellows do have flappers. Can not find any info showing if the original parts had flappers or not. I guess it won't cause any problems using the ones with internal flappers.

 

[QBhoy]

Sorry to hi jack. Someone on here recently enlightened me about VP not having exhaust flappers (the same way merc have them in cow horn)...but one of the posts above maybe suggests that that only refers to certain years or period ?
So, question for me is...do some have and some not, or just they don’t right across the board ?
thanks.

 

[Maclin]

The older white models (270/80/90,DPA) do not have thru-hub exhaust. The exhaust routed thru the anti-cav plate. Some models had a flapper at the end of that, some had it in the exhaust bellows that runs from the transom to the outdrive.

My 1991 570/DP had a flat wide and hollow anti-cav plate, and the flapper was riveted on at the end of it. At rest it was "closed" unless the engine was running. Here is a pic of the drive tilted up, straight on, flapper marked in crayon...

 

[bruceb58]

Ok great, any IO equipped with flappers should have them if you want to avoid water being ingested into the motor. Is that better?

Except for the few years of Volvos that did have them and then there was a bulletin to remove them!!

 

[QBhoy]

Haha. Hence my confusion.
Thsnks maclin and Jimbo.
So not that it matters now, I don’t have the boat anymore, but my 1989 sealine has a AQ205 (4.3) coupled to a 290DP exact same as picture maclin posted and with flap on exhaust on drive...but the paint was a light grey, not white. Would that have flappers in cow horn or not ? I suppose it might matter, my friend now owns an identical set up.
Thanks and sorry to hi jack again.

 

[Maclin]

Would that have flappers in cow horn or not ?

Not.

I should not have limited the scope in my post to one color of those drive models.

 

[Addis]

Information manual for the installation of the exhaust bellows. http://boatinfo.no/lib/volvo/manuals/aq280-dpc_drive.html#/0