- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
My 2008 Cummins diesel engines have just under 800 hours. They get used regularly, though not as much this past year as we have been building a house. We have used the boat more often in the last couple of months.
The #2 cylinder on the stbd motor is not firing at idle, but runs great above about 50% load.
1) Can hear the odd idle sound in exhaust - missing
2) Placing finger on fuel line provides very little vibration on #2, all other cylinders kick the fuel lines a little
3) At 1000 RPM, out of gear, cylinders measure about 165 degrees, #2 measures about 150
4) In gear low RPM, port engine load is about 30 and stbd is about 45
5) As you advance the power, it feels like the stbd prop is bent - pulled boat and tuned props
6) After about 50% load, the loads level up (stbd vs port), vibration goes away.
7) Tested wide open 2680 RPM each (same as always). 25 gph each. 33.5mph. 98% load.
8) After wide open test, load at idle in gear was closer to port, about 30/40 instead of 30/45.
Yes, I need to change the fuel filters - I have them, and am definitely behind on this.
So, I assume it is an injector issue. I'll change the filters and over-treat the fuel.
1) What do I treat the fuel with?
2) Will I do damage to treat the fuel and run the boat?
3) If no change, what are my next steps?
Thank you.
The #2 cylinder on the stbd motor is not firing at idle, but runs great above about 50% load.
1) Can hear the odd idle sound in exhaust - missing
2) Placing finger on fuel line provides very little vibration on #2, all other cylinders kick the fuel lines a little
3) At 1000 RPM, out of gear, cylinders measure about 165 degrees, #2 measures about 150
4) In gear low RPM, port engine load is about 30 and stbd is about 45
5) As you advance the power, it feels like the stbd prop is bent - pulled boat and tuned props
6) After about 50% load, the loads level up (stbd vs port), vibration goes away.
7) Tested wide open 2680 RPM each (same as always). 25 gph each. 33.5mph. 98% load.
8) After wide open test, load at idle in gear was closer to port, about 30/40 instead of 30/45.
Yes, I need to change the fuel filters - I have them, and am definitely behind on this.
So, I assume it is an injector issue. I'll change the filters and over-treat the fuel.
1) What do I treat the fuel with?
2) Will I do damage to treat the fuel and run the boat?
3) If no change, what are my next steps?
Thank you.