I know this is a very discussed topic, but I am unable to find threads where a definitive solution was reached so here goes.
I have a year 2000 Cobia 244 CC with twin F115's and the port engine is not reaching full RPM. Last year the throttle position sensor stuck, and it was surging so I got that replaced, and now it's back to only doing about 4600 RPM max. Starboard engine reached 5800-5900 easily and that puts the boat into a good left turn lol.
I have done the following:
New filters all around.
Cleaned VST filter
Changed VST tank o-ring.
New spark plugs (hotter for F90)
New matched flow injectors.
New thermostat
Replaced low pressure pump diaphragm.
New grommet and spring.
Compression test shows all cylinders within 14% of each other so I think they are OK
The engine does "make oil" I have kept it changed regularly.
All I have read points me next to the high pressure fuel pump and checking the pressure reading under load. I have no clue how to do this and I have seen a Schrader valve on top of the fuel rail, is this the best point to take that reading? What is the name of the part I need to check the fuel pressure?
Thanks in advance!
I have a year 2000 Cobia 244 CC with twin F115's and the port engine is not reaching full RPM. Last year the throttle position sensor stuck, and it was surging so I got that replaced, and now it's back to only doing about 4600 RPM max. Starboard engine reached 5800-5900 easily and that puts the boat into a good left turn lol.
I have done the following:
New filters all around.
Cleaned VST filter
Changed VST tank o-ring.
New spark plugs (hotter for F90)
New matched flow injectors.
New thermostat
Replaced low pressure pump diaphragm.
New grommet and spring.
Compression test shows all cylinders within 14% of each other so I think they are OK
The engine does "make oil" I have kept it changed regularly.
All I have read points me next to the high pressure fuel pump and checking the pressure reading under load. I have no clue how to do this and I have seen a Schrader valve on top of the fuel rail, is this the best point to take that reading? What is the name of the part I need to check the fuel pressure?
Thanks in advance!
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