The whole discussion is on the other thread.
To give you a quick rundown/summary:
Yanmar 4JH4 TE
127 hours total time from new (2013). Was running to full revs according to PO.
New Flexofold prop.
won't rev past 2000 both in gear
AND in neutral, ie; no load condition.
New complete exhaust system. New Turbo. New elbow
, New Vetus waterlock/muffler
New Vetus exhaust hose, New outlet, continuous fall from top of loop to outlet. Just tested exhaust back pressure at 10kpa (half the Yanmar spec limit)
Removed the hot water service
and put in a small bypass hose. (not relevant really, but possibly disabled the cold start/pump time retard system, if there is an airlock in the bypass hose)
New complete fuel
system. Clean/spotless fuel tank
, New Racor
, New fuel lines (return line too), New secondary cartridge. Tested with a fuel tank
connected direct to the pump
inlet, no difference.
I havent checked the valve/tappet clearance
The fuel pump
is looking like the next check (I think)
The fuel tank was dirty with algae/crud in the bottom, I guess its possible some crud has entered the fuel pump
, although there has always been 2 filters between tank and pump
. Low hours and little use, algae growth in the pump??
Engine sounds as sweet as, certainly running on all 4 up to 2000
Notably it wont go above 74 degrees
I ran it at full throttle under load for 2 hours recently, no excess smoke and no change at the end of the run to the max rpm (still 2000)
All thoughts gratefully received.