Wanted to say thank you to everyone on this thread for excellent advice and coaching on helping me tune my engine. I'm on an island and would have faced 2-3 weeks with no boat had i taken to certified mechanic (major backlog on the lake).
For others who may be experiencing some issues, here is what i did and the outcome. My wife proclaimed yesterday that the engine was much quieter and smoother - success!
- 200 hours, 8 year old 130HP ETEC Gently used. Last service at 5 year mark
- Issues: constant over heats despite water pump replacement, and large intake grills, not as smooth sounding as it was at new
- After fixing PRV started getting weird issues with not being able to hit WOT RPMs
1) Replaced PRV spring with lighter spring. This was a PITA repair but wow what a difference - no more overheats!!! However issue with not being able to hit WOT RPMs and strange improved fuel economy readings
2) Added Fuel Liner cleaner in heavy dose and did Engine Tuner service
3) Suspected Exhaust hose and fitting going from EMM to Engine - sure enough it was crumbling and in bad shape (from all the overheats?). Removed damaged hose, clean restrictor and replaced with new nipple
4) Replaced VST filter as well - it was pretty gummed up
5) Checked exhaust valve and it was working smooth - sprayed some engine tuner in there and re-greased actuator arm and seal as per manual
6) Replace Fuel filter
7) New Spark Plugs properly indexed to Hex key
Results = much smoother running engine especially at top end (quieter). It was after i fixed the exhaust hose that things seemed smoother. The biggest improvement is not overheating the engine when tubing with kids - was always such a downer having to stop a tube ride
What's next? looking for a prop that will have me at 5800-5900 at WOT.