Greetings! I've been lurking for a while reading up on all I can to try to get a new to me 2003 Honda BF90a going for the season. Have learned a lot here and using the information found, have been narrowing things down, testing, cleaning and replacing some stuff until I hit upon the possible issue(s) and wanted to see if I'm on the right track. Boat (engine) is heading into a local shop with Honda technicians but I wanna do all I can before then! The engine initially had a CLEAN dipstick with what looked like brand new oil and fired up prior to purchase but had a misfire in cylinder 4, showed 509 hours and well, the Honda name sold me. It now starts n runs awesome after replacing plugs n coils but... Did an oil change and it was chocolate milk!? and very dark but no silvery metal bits at all. Changed oil n filter... Solid pee stream from the engine and inspected/replaced the thermostat that was stuck wide open. A bit of build up in that housing can be seen but not bad. Compression tested (warmed up and with throttle as far open as I can in neutral cuz it won't turn over in gear/wide open, tested at a 195-200 psi across all 4) and running it on muffs, idles and the allowed bit of throttle up (not in gear) sounds great. Went to local lake for about a half hour to take her for a spin and in neutral with engine cover off, I can manually bring up RPM's to the amount allowed, the engine sounds great... In gear as I throttle up it hits a spot, lower rpm than when I tried in neutral, that makes it sputter and run rough almost dying. Max speed according to fish finder (Tach not working/fixing tomorrow) it was 7mph. Temp light was off and oil light on and green. Oil light turns off when engine alarm sounds then turns back on but did not die or shut down. Limp mode? Limped back and headed home for more work. Oil still looks great on the stick but I took a 1oz sample from the drain plug. Still transparent as in no water but very black from possible exhaust leak? Bought a 'tub' to put the entire lower section into and while in neutral or lowest RPMs in drive, exhaust isn't consistently coming from the prop area but rather from another seam in the case a couple inches up, not far from water inlet. Exhaust DOES come from prop when in gear, higher rpm's on the lake...
Do I have an exhaust leak into the oil somehow which in turn throws it into limp mode and maybe some moisture as well? I've read that the exhaust goes through the oil pan and there are lower seals that need to likely be replaced. Oh and oil pump/sensor may need replacing?
Thanks in advance.
Do I have an exhaust leak into the oil somehow which in turn throws it into limp mode and maybe some moisture as well? I've read that the exhaust goes through the oil pan and there are lower seals that need to likely be replaced. Oh and oil pump/sensor may need replacing?
Thanks in advance.