Serial # 1E003251 bought new in 08 @ 600 hrs. Always run a fuel cocktail in every tank.
Started up and ran fine as normal, fished for several hours without issue, but on one start-up after fishing a spot for 20 mins the engine started but idled very rough and stalled, 2 more attempts with the same results, with a lot more smoke the normal. 4th try I was able to get it in gear and throttle up and get it on plane without any alarms or performance problems, It ran fine up on plane at 4k rpm. So I stopped and turned off the motor waited 10 seconds and re-fired no problem. So I continued to fish a few more hours but every time I let the motor set for any length of time, the same problem would occur. One attempt to re-start the engine went to a fast idle and I got the high rpm in neutral alarm but stopped when idle slow to a rough idle. I did notice if I trimmed the motor up while fishing a while it seemed to help restart, not as rough an idle it seemed. Got it home and the next day put it on the hose and fired it up no issues, several restarts and still no issues until I let it sit for a while after the engine had warmed up. Any ideas ?
So far I have performed the following tests-
Inspected spark plugs they have less then 50hrs and look good, light to medium tan gapped at .042
Checked the tracker diaphram for holes - all good.
Air pressure at rail -95 psi / maintained pressure for 10 sec (mercury racing spec)
Fuel pressure at rail- 112 psi / maintained pressure for 10 sec
Compression- 120-125 on all 6
Reed valve inspection, no visible chips, cracks or broken reeds will measure gaps tomorrow.
Visual inspection of fuel injectors, very clean no corrosion or build up on tips, o-rings good.
Visual inspection of Air injectors , very small amount of carbon on tips wiped of easily, o-rings good.
Inspected thermostats and tested open at 130 degrees-no debris found.
I will do a spark test after I reassemble. I think I will install a new set of reeds while I have it down as well as get the injectors cleaned, but they look so good almost seems a waste..lol. But I want the piece of mind since its never been done. Reeds were done once 300 hrs so might as well, may give the TDR's a try.
Need some help as to what to try next ?