Re: Another Yanmar Exhaust Mixing-Elbow Question
As a tech, i have seen all kinds of failures of both, the OE exhaust and the aftermarket equivalent. In my experience, you get what you pay for.
The premature carbon blockage is due greatly to the lack of attention paid to the operation of the engine, and if they are removed occasionally and cleaned it becomes a non-issue. The larger concern with the aftermarket, in my experience, is the material failures both internal and external. It happens most frequently at the welded seams but i have also seen them simply crack along the tubing.
Which ever you decide to use, have it removed and inspected every year or two during your major service. Let someone else have the nightmares.