Yanmar overhaul after 1400hrs

[teejayevans]

After a period of couple of months in the marina, I started the engine to head out for a short trip. Engine started fine, I motor out and as I passed through a span of bridges I smelled what I though was burning rubber, I checked below and saw nothing or smelled nothing and a quick glance of exhaust show nothing so I assumed it was from vehicles on the bridges, I kept going, after another mile and clear of the bridges I still smelled it, rechecked the exhaust show it was a little black and the water was black as well, I pulled over and as so as I put the engine into idle it died.
I eventually tried to restart and there was a horrible noise coming from my electric fuel pump (Walbro 6803?), so I end up replacing and check the engine fuel filter, it was blackened and had small rubber bits. I emptied the fuel tank, the fuel was black and found more rubber bits in the tank. I pulled the injectors and the needle valves were frozen. So after having them serviced and cleaning fuel tank and replaced filters, restarts fail, compression check were low (300-320).
It was diagnosed as stuck rings, I had to have the engine pulled, hone and new pistons, injection pump serviced, etc.
My thinking is I got some bad fuel (with alcohol?) and the rubber disintegrated getting pass the engine filter, resulting in burning rubber, which caused the rings to stick along with the injectors.
I've now added a second filter after the electric fuel pump (Walbro FRB13, is ethanol safe) as a preventive measure.
I thought I post this as food for thought...