Carey'd Away
New Member
Hell0 All,
I am new to the forum and looking for help/input:
We recently rebuilt one of the Man 1050HP diesels (Port Motor) in our 2003 Sunseeker. Shortly after the rebuild, we started to experience a surge at higher RPM on that motor only.(1600 RPM and up). Basically we would be running along and and it would feel like we pulled the throttle back momentarily and then right back to where we started. The drop is appx 200 RPM's and ever so quickly it recovers. The only visual we have is the tach is bouncing just prior to the surge.
We were out a few weeks back and now the engine is not throttling past 1600 to 1650rpms: As if it were in Limp mode. So no turbo's coming in. I have checked all codes and nothing, no overspeed warnings etc. Now the tach bounces all the time.
A little history: We went through and swapped speed sensors engine to engine, ran the engine from a fuel bucket rather than the tank to be sure there was not a fuel issue, checked fuel pressure at lift pumps and fuel pump, all normal readings, both at idle and under power. Swapped black boxes, (now back to where they are supposed to be). Replace the throttle cable to the sendor on that motor. Swapped Tach heads, removed and checked shuot off solenoid. We pulled and had the injectors checked. Found that the injectors are opening at pressures higher than the spec. Supposed to open at 280 bar, they are opening between 300 and 350 bar. The shop shimed the nozzles and retest. Boat ran perfect for about 30 minutes and started doing it again.
I am sure I am missing some inforation here, but hope someone might have heard of this before to give us another place to look??
Thanks in advanced. Carey
I am new to the forum and looking for help/input:
We recently rebuilt one of the Man 1050HP diesels (Port Motor) in our 2003 Sunseeker. Shortly after the rebuild, we started to experience a surge at higher RPM on that motor only.(1600 RPM and up). Basically we would be running along and and it would feel like we pulled the throttle back momentarily and then right back to where we started. The drop is appx 200 RPM's and ever so quickly it recovers. The only visual we have is the tach is bouncing just prior to the surge.
We were out a few weeks back and now the engine is not throttling past 1600 to 1650rpms: As if it were in Limp mode. So no turbo's coming in. I have checked all codes and nothing, no overspeed warnings etc. Now the tach bounces all the time.
A little history: We went through and swapped speed sensors engine to engine, ran the engine from a fuel bucket rather than the tank to be sure there was not a fuel issue, checked fuel pressure at lift pumps and fuel pump, all normal readings, both at idle and under power. Swapped black boxes, (now back to where they are supposed to be). Replace the throttle cable to the sendor on that motor. Swapped Tach heads, removed and checked shuot off solenoid. We pulled and had the injectors checked. Found that the injectors are opening at pressures higher than the spec. Supposed to open at 280 bar, they are opening between 300 and 350 bar. The shop shimed the nozzles and retest. Boat ran perfect for about 30 minutes and started doing it again.
I am sure I am missing some inforation here, but hope someone might have heard of this before to give us another place to look??
Thanks in advanced. Carey