2 exhuast points on my 4.3 Volvo Penta

[jimi]

My I/O is very noisy when on plane. I recently borrowed a noise meter and discovered that the VAST majority of the noise comes from over the stern (by several orders of magnitude!).

The volvo penta stern drive has a standard thru hub exhuast like almost all engines these days (I/O and outboard). BUT it also has a second port (1.5" x 4") located in the stern drive where most of the exhaust comes out of (becuase it is above the water and therefore less work).

Anybody know why there are two exhuast paths?

PS Only serious replies. No "your engine will blow up" posts please.

 

[Don S]

Re: 2 exhuast points on my 4.3 Volvo Penta

Your picture is way to small to see. Have you pulled the drive and checked for obstructions in the exhaust passages? also pull the prop and look from that side also.

 

[jimi]

Re: 2 exhuast points on my 4.3 Volvo Penta

I love google

This is what I'm talking about Don.

http://http://www.volvopentastore.com/Exhaust-Cover-for-Shield/dm/store_id.366--view_id.311247

 

[jimi]

Re: 2 exhuast points on my 4.3 Volvo Penta

The Volvo Penta store says "In order to comply with strict regional noise limitation requirements, Volvo Penta has developed exhaust cover kits for shields and drives. The kits are intended for 3.0 and 4.3 gasoline engines with SX drive."

Has anyone heard of this?

 

[Don S]

Re: 2 exhuast points on my 4.3 Volvo Penta

There is a bulletin out on the 3.0, but it's not approved for the 4.3