I have a 2007 Mercury 90ELPT 4S
Serial # 1B522264
It's very hard to start, takes 8 to 10 tries. Sometimes runs ok afterwards and starts normally after warmup. I checked to following:
Battery load test: very good
Checked all fuel lines and filters: all good.
Replaced anti-siphon valve just in case.
Replaced both fuel filters-no debris in filters.
Opened and checked the FSM. Both pumps work, bowl switch works properly. Screens clean and fuel pressure regulator hose as new.
Key on lift pump fills housing and high pressure pump runs fuel pressure is between 40-50 PSI.
Once started, fuel pressure stays 40 to 50 and creeps upward to about 70 at idle and high idle. I get a critical alarm shortly afterwards.
The fuel pressure seems high (even giving the accuracy of the gauge kit some leeway) and I am stumped as to why.
I don't have the diagnostic software and am trying to work through this myself, as I have decent mechanical skills. Anyone have any ideas to further narrow this down? Mercury parts are expensive and I am trying to avoid buying parts that aren't the trouble.
Suggestions very much appreciated.
Tim
Serial # 1B522264
It's very hard to start, takes 8 to 10 tries. Sometimes runs ok afterwards and starts normally after warmup. I checked to following:
Battery load test: very good
Checked all fuel lines and filters: all good.
Replaced anti-siphon valve just in case.
Replaced both fuel filters-no debris in filters.
Opened and checked the FSM. Both pumps work, bowl switch works properly. Screens clean and fuel pressure regulator hose as new.
Key on lift pump fills housing and high pressure pump runs fuel pressure is between 40-50 PSI.
Once started, fuel pressure stays 40 to 50 and creeps upward to about 70 at idle and high idle. I get a critical alarm shortly afterwards.
The fuel pressure seems high (even giving the accuracy of the gauge kit some leeway) and I am stumped as to why.
I don't have the diagnostic software and am trying to work through this myself, as I have decent mechanical skills. Anyone have any ideas to further narrow this down? Mercury parts are expensive and I am trying to avoid buying parts that aren't the trouble.
Suggestions very much appreciated.
Tim
