Pietro
Active Member
So, last week-end was the first to the islands. Some 40 miles off-shore. The boat, though shiny as new, did not go well… the engines seemed to have lost 40% of their power!
Engines accelerated up to 2300 RPM, then portboard was not able to go past that figure, and starboard only reached 2500. So I set the rpm to 2300, 22kts and an unbelievable 17 gph per engine!!! This is what they normally burn @ 2500 rpm.
I thought there was something in the port engine as it was not able to exceed 2300 rpm. Or was it fuel?
Hull and props perfectly clean, no smoke from the exhausts, new Racors…strange...
This morning I tested the boat on a perfectly flat blue sea with my Caterpillar mechanic. Pressure gauges connected to the turbos.
After warming the engines up, I pegged the throttles and… starboard clutch slipped!!! The engine revved up as the boat was turning to starboard as the only engine engaged to its prop was the starboard one…
After some adjustments, the gear started working again and afterwards my 390 run like crazy. 2900 rpm, 29.5 kts with ¾ fuel and water and 4 big guys aboard. No vibration from the props! Stunning!
Later today the mechanic will check oil pressure in my Twin Disc transmissions and I will install oil pressure gauges.
I’ve learned another lesson… :smt001
Engines accelerated up to 2300 RPM, then portboard was not able to go past that figure, and starboard only reached 2500. So I set the rpm to 2300, 22kts and an unbelievable 17 gph per engine!!! This is what they normally burn @ 2500 rpm.
I thought there was something in the port engine as it was not able to exceed 2300 rpm. Or was it fuel?
Hull and props perfectly clean, no smoke from the exhausts, new Racors…strange...
This morning I tested the boat on a perfectly flat blue sea with my Caterpillar mechanic. Pressure gauges connected to the turbos.
After warming the engines up, I pegged the throttles and… starboard clutch slipped!!! The engine revved up as the boat was turning to starboard as the only engine engaged to its prop was the starboard one…
After some adjustments, the gear started working again and afterwards my 390 run like crazy. 2900 rpm, 29.5 kts with ¾ fuel and water and 4 big guys aboard. No vibration from the props! Stunning!
Later today the mechanic will check oil pressure in my Twin Disc transmissions and I will install oil pressure gauges.
I’ve learned another lesson… :smt001