370Dancer
Well-Known Member
- Oct 2, 2006
- 2,489
- Boat Info
- 1998 370 Sundancer
- Engines
- 380hp MAG MPI Gen VI with V drives
I am also posting on marineengine.com's forum. Someone was confused about the excel sheet data readings. I posted this clarification. Now I'll post it here if anyone missed what I was doing....
The results are attached as an Excel file. If you need it in another format, just ask.
While you are looking at this, I am going to recheck fuel pressure compared with Starboard, and put another fresh set of plugs in it. There's a txt file of next stuff to try. The only mechanical thing I found so far was a valve rocker that had been punched thru by the lifter push rod, which was preventing the valve from opening much. I thought that was really going to be it, but I still can't top out in RPMs.
Ask away, I'm all ears.
I took the boat out for a ride.
I have Fox Marine real time engine monitoring gateways for each 1999 MEFI engine that display over NMEA 2000, and a Bluetooth app on my iphone. During the ride, I took 5 samples (screenshots of the app displaying all these parameters)
the notes below each set of readings on the excel page describe what I was doing.
In the first sample engine run time of 11.5 minutes, I set the throttles so each engine's TPS was reading the same, 10.16%, looking for variations in other readings
In the second sample engine run time of 12.5 minutes, I set the throttles to synch (or near it) of 1671 RPMs, looking for variations in other readings
In the third sample engine run time of 15.5 minutes, I set the throttles to around 2000 rpm, where the Port engine starts to really need more throttle than the Starboard to keep that RPM.
in the fourth sample engine run time of 18.5 minutes, I tried to plane out the boat. The Port engine got to 2430 RPM at full throttle, while the Starboard easily got to 3006 RPM, with only 45% throttle being applied. I saw no point in running the Starboard up to full throttle as I know that already is doing fine at 4600+. Fearing potential damage to the Port engine, I backed off to my normal slow cruise where both engines are "kind of" acting the same.
In the 5th sample engine run time of 58.5 minutes, I took one more reading at around 1800 synched RPM to see if anything had drastically changed over time.
The charts were just me looking at various parameters over the samples comparing the Port to the Starboard engine, looking for patterns.
The list of observations under the sample data are my notes of what I see looking at the comparisons.