I have a 1993, 60 degree 175 that was recently mounted as a twin. The compression is consistant and initially the motor seemed to run well both at idle and high speed. I went through a period of fuel problems as I bought some mid-grade with water in it. This has been solved and the other motor runs perfect.
Prior to taking the boat for an in the water test, I cranked both motor while on the water hose. Both seemed to run fine. Then the starboard (the one i'm complaining about) began running very rough and wouldn't stay running.
I put the boat in the water and the motor ran the same. At time it would plane and it seemed that the motor would clear itself out. If you gave it more gas it would run rough until and then clear out.
I have replaced the plugs, put a new water sep. on, pulled all carbs and cleaned (found no trash. I did not replace gaskets.), put vinyl tubing for fuel line, swaped fuel lines w/good running motor, bypassed water sep., filter on front of motor is clean.
With the motor in a tank, it runs better but still chugs. It will rev. up great but when held a higher rpm than idle, it still chugs. Keeping the primer bulb pumped doesn't seem to help.
The spark plugs I replaced were not old but were black. The new plugs do not get black but are wet when pulled after running. A timing light shows all are firing.
When the engine dies, it will usually start right back up. Sometimes it will take a bump on the choke.
unless I am missing something, the carbs are only metered by the needle valve on float and the high speed orifice.
My next attempted fix is to put new gaskets on the carbs as they may be sucking air. Any help would be greatly appreciated
Prior to taking the boat for an in the water test, I cranked both motor while on the water hose. Both seemed to run fine. Then the starboard (the one i'm complaining about) began running very rough and wouldn't stay running.
I put the boat in the water and the motor ran the same. At time it would plane and it seemed that the motor would clear itself out. If you gave it more gas it would run rough until and then clear out.
I have replaced the plugs, put a new water sep. on, pulled all carbs and cleaned (found no trash. I did not replace gaskets.), put vinyl tubing for fuel line, swaped fuel lines w/good running motor, bypassed water sep., filter on front of motor is clean.
With the motor in a tank, it runs better but still chugs. It will rev. up great but when held a higher rpm than idle, it still chugs. Keeping the primer bulb pumped doesn't seem to help.
The spark plugs I replaced were not old but were black. The new plugs do not get black but are wet when pulled after running. A timing light shows all are firing.
When the engine dies, it will usually start right back up. Sometimes it will take a bump on the choke.
unless I am missing something, the carbs are only metered by the needle valve on float and the high speed orifice.
My next attempted fix is to put new gaskets on the carbs as they may be sucking air. Any help would be greatly appreciated
