STB
Guru
Hi all,
I just wanted to post an update. Sorry it is slow in coming. I just got the boat back. It was at the yard for 2 months. It ended up needing props, struts, and a shaft, as well as the previously anticipated bottom prep and paint and usual through-hull and packing gland maintenance. I took it to Gambol Industries in Long Beach. Jeff there was really helpful and patient with a new boat owner. The delays were mostly because I authorized the work one step at a time, which stacked the part delays. The props came via Gary at Wilmington Propeller, who was also great to chat with. (And, usual thanks to S&W Diesel for their help with engines, e.g. new thermostats, tach sender, stop solenoid, etc).
At any rate, recall that I have 2x Perkins 6.354 MGT turbo 185HP "breadbox" engines and was told WOT RPM under load should be about 2450. The props on the boat when I got it were 23x21x1-3/8" (and very corroded). I was seeing about 2050-2100RPM and 14kn/h WOT and it started to let loose some grey smoke at about 2000RPM. The RPM was verified with an optical counter from Amazon, as was suggested here.
I replaced the props with 23x19x1-3/8, losing 2" of pitch, to try to increase the WOT RPM by 400 (200RPM per 1" of pitch).
I got the boat back and gave it a brief test run. It looks like it worked perfectly. I saw 2450RPM WOT and the grey smoke kicked in at about 2400, maybe 2350. The wind wasn't stead and I didn't run back and forth enough to get a good measure, but my GPS was reading 14.5kn/h - 15kn/h, so I don't think the pitch change cost me much, if anything, in speed.
I checked in with Bob at S&W Diesel and he told me that was perfect, because I was just beginning to over-fuel at the very top of the RPM range. He said that I could adjust the prop by a hair to get rid of it totally -- or just do the wiser thing and run the engines nowhere near that hard. He suggested a cruise of 2000-2100RPM. I was mostly going slower, e.g. 1800RPM last weekend, so I'll see how 2000 feels next weekend.
I get some white smoke (not steam) before I leave the slip. I've been told it is to be expected with the Perkins engines of that era, but I'm probably going to have the injectors rebuilt on one of them and see it it cleans it up any. I'll post again in a few weeks or couple of months to update about how that works.
At any rate, I just wanted to let anyone interested know how the prop change affected things.
Cheers!
-Greg
I just wanted to post an update. Sorry it is slow in coming. I just got the boat back. It was at the yard for 2 months. It ended up needing props, struts, and a shaft, as well as the previously anticipated bottom prep and paint and usual through-hull and packing gland maintenance. I took it to Gambol Industries in Long Beach. Jeff there was really helpful and patient with a new boat owner. The delays were mostly because I authorized the work one step at a time, which stacked the part delays. The props came via Gary at Wilmington Propeller, who was also great to chat with. (And, usual thanks to S&W Diesel for their help with engines, e.g. new thermostats, tach sender, stop solenoid, etc).
At any rate, recall that I have 2x Perkins 6.354 MGT turbo 185HP "breadbox" engines and was told WOT RPM under load should be about 2450. The props on the boat when I got it were 23x21x1-3/8" (and very corroded). I was seeing about 2050-2100RPM and 14kn/h WOT and it started to let loose some grey smoke at about 2000RPM. The RPM was verified with an optical counter from Amazon, as was suggested here.
I replaced the props with 23x19x1-3/8, losing 2" of pitch, to try to increase the WOT RPM by 400 (200RPM per 1" of pitch).
I got the boat back and gave it a brief test run. It looks like it worked perfectly. I saw 2450RPM WOT and the grey smoke kicked in at about 2400, maybe 2350. The wind wasn't stead and I didn't run back and forth enough to get a good measure, but my GPS was reading 14.5kn/h - 15kn/h, so I don't think the pitch change cost me much, if anything, in speed.
I checked in with Bob at S&W Diesel and he told me that was perfect, because I was just beginning to over-fuel at the very top of the RPM range. He said that I could adjust the prop by a hair to get rid of it totally -- or just do the wiser thing and run the engines nowhere near that hard. He suggested a cruise of 2000-2100RPM. I was mostly going slower, e.g. 1800RPM last weekend, so I'll see how 2000 feels next weekend.
I get some white smoke (not steam) before I leave the slip. I've been told it is to be expected with the Perkins engines of that era, but I'm probably going to have the injectors rebuilt on one of them and see it it cleans it up any. I'll post again in a few weeks or couple of months to update about how that works.
At any rate, I just wanted to let anyone interested know how the prop change affected things.
Cheers!
-Greg
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