@skyman2112 Good point on the distributor/rotor. It's been several years since they were replaced. Ordered new ones, and will put on the muffs and test pulling the #2 plug wire after I get them installed.
I'm not sure what exactly is happening, but here are the plugs on the cylinder in question, and the cylinder on either side of it. Not sure what this pattern might indicate to an experienced tech... But it starts well and runs pretty smooth on the muffs...
@Bondo, good thought on the fuel filter. I always keep a new one on hand but only change every other season. I put about 20-25 hours a season on the boat. Just changed it, and everything looked great.
I have a 2002 Mercruiser 5.0 MPI in a Crownline 225BR that just started to have a misfire under load. 409 hours. I've owned the boat since 2009 and have personally serviced it regularly. First time out this year it had a slight vibration, and was extremely down on power while trying to take...
That is exactly what it looks like was happening.
This is a buddies boat, and it is stored in high & dry indoor racks, so he just pays the marina to do all the maintenance. They boast that all of their mechanics have 20-30 years experience, so you'd think they could handle a simple oil change...
@dubs283 - Your WAG was apparently spot on. I was surprised when my 5 quart container did not hold all the drain oil, but you coulda bought me for nickel when I sucked another 2 quarts and 4 ounces out of the motor.
Just wanted to give you all an update on this. I believe I have this issue resolved. I put a mechanical oil pressure gauge on and took the boat out for a full throttle run 3-4 miles up the lake. Watched oil pressure steadily fall into the low 30's. Pulled it back to an idle and had the valve...
Interesting. I've only ever used Volvo 10w40 (in both dino & synthetic) in this engine as that is what they recommend. I wonder why Merc recommends a heavier weight than Volvo in essentially the same engine.
