Yngmar
Well-known member
This is what my exhaust connector looked like after I believe 14 years (new to me boat, but everything points to this never having been removed before). That's the bit on the MD22L-B exhaust elbow where the spent raw water goes in the elbow before joining the exhaust gas.
It was clogged except for a ~6mm diameter hole, not to mention the metal had actually crumbled away below the hose and hose clip (which lead to it leaking). The connected hose, apart from having turned porous had significant buildup too, but tapering off towards the heat exchanger, where there was no residue at all. I found this interesting, as the black crud must be exhaust gas residue, and to find it there must mean it gets blown quite a bit into the raw water system back from the elbow. The yellow stuff in the most recent layer must be from the antifreeze used to winterize the raw water system.
Engine is running fine by the way, although I'll be taking off the elbow in the near future to take a peek in there as well (and probably the heat exchanger insert too).
Thought this picture was worth sharing
It was clogged except for a ~6mm diameter hole, not to mention the metal had actually crumbled away below the hose and hose clip (which lead to it leaking). The connected hose, apart from having turned porous had significant buildup too, but tapering off towards the heat exchanger, where there was no residue at all. I found this interesting, as the black crud must be exhaust gas residue, and to find it there must mean it gets blown quite a bit into the raw water system back from the elbow. The yellow stuff in the most recent layer must be from the antifreeze used to winterize the raw water system.
Engine is running fine by the way, although I'll be taking off the elbow in the near future to take a peek in there as well (and probably the heat exchanger insert too).
Thought this picture was worth sharing
