Looking for some expert help,
I bought this 2008 Mercury optimax 115 used and ran it roughly 30 hours Before it died on me crushing at about 4000 rpm. It quickly restarted and I got it back to the dock. It acted as if someone turned the key. Very familiar with 2 strokes So I did a Compression test due to a slight misfire. It turned out that the number 2 cylinder was sitting at around 75 psi. With the other two (cylinder 1 and 3) being at 120 psi. I took it to a local Mercury guy and he said that the poppet valve and thermostat caused the piston to burn up due to sand and debris. Fast forward I had the center cylinder honed and installed a new piston with everything in spec; New thermostat and poppet valve also. Got the engine back together and started right back up. I did the optimax break-in procedure with the oil pump also. I Put it on the water and it lasted about 20 minutes. Would start back up after letting it sit for a bit. Got it started and sounded horrible so I shut it off and got it back to the dock. Compression test again and barely read anything. Pulled it all apart and the piston is scored all the way around. This time block will have to be bored. Really seems like there is no oil to lubricate the piston but the crank was covered in oil. One thing to note that the wrist pin and bearing were dry as a bone but the lower part of the connecting rod was sufficiently lubed. Would an injector cause this ? I’ve been through the oil lines and nothing is blocked. Any advice at this point would be greatly appreciated. Definitely don’t want to put it back together and have it burn up again. Thanks in advance.
Reply With Quote
