nveater
Veteran Member
- Joined
- Nov 4, 2021
- Messages
- 77
- Vessel Name
- Pathfinder
- Vessel Make
- Mainship Pilot 30
I have 210hp Cummins 6BT-5.9M engine driving a 1999 Mainship Pilot 30. At the beginning of the season I was getting an average speed of about 12.7 kts at cruise (2400 rpm) and about 15.6 WOT (just shy of 2600). More recently the average speed has dropped to about 10.2 and 12.5 respectively. I have dived on the boat and there is nothing around the prop and the bottom is "normal" for this time of year . The engine sounds fine and all the other indicators (oil, temp etc) are where they always are. I have taken tides and currents etc into consideration . It shouldn't be the prop as the existing prop worked fine in the beginning of the year. I do have vacuum gauges on my fuel filters and the readings have not changed. I do not have a boost instrument, but I was wondering if it could be the turbo air filter ? I have never serviced or changed the filter in the 3 years of owning the boat ? Would welcome any ideas as I ponder this conundrum. Thanks