D4-300 Drain Water from Exhaust System

[Bosn Mate]

Good Afternoon:

Completing my final maintenance check for this season and found the following in the Volvo Penta D4, D6 Operator's Manual (page 66):

"Boats with reverse gear - Drain the water from the exhaust system to prevent water entering the engine while the boat is being transported by trailer."

I looked this up in the Volvo Penta Service and Maintenance Manual and could not find a reference to draining water from the exhaust system.

Appreciate clarification on this issue.

Thanks!

Mike

 

[BB marine]

I'm not completely sure what the manual is referring to but I'll give it a stab. If there are low spots in the exhaust system that water can lay in between the mixing elbow to the exhaust thru hull. There is a possibility of water sloshing around and making its way back up into the exhaust elbow and manifold. If you are worried about this remove the drain plug at the bottom of the muffler this will insure this will not happen. I was told that the additional pocket tube installed on the lower portion of the muffler is to help prevent this from happening.


If you look under the blue trident exhaust hose you will see the pocket tube facing fwd. That is installed to help eliminate the water from backing up.