caltexflanc
Guru
His emphasis on SOG, among other things, indicates any semblance of intelligent thought has had little to do with his opinion.
run just one of the two motors?
- Thread starter robs523
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His emphasis on SOG, among other things, indicates any semblance of intelligent thought has had little to do with his opinion.
Tomas
Senior Member
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- Dec 3, 2010
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- 207
I have Velvet Drive transmissions. The owners manual says the transmissions will not be damaged by operating a twin engine boat at sailing or trolling speeds (under 7kts thru water?). There is no question running a twin engine boat on one engine will halve the routine maintenance expense. The question of fuel savings is another matter. If you run single engine at the same RPM as you would normally run both engines and accept the reduced SOG, you will use probably use slightly more than half as much fuel. If you run single engine and wish to equal twin engine speed, you will have little if any fuel savings. I ran close to 2000 miles of the loop single engine. As far as handling in ICW waters and calm open water, the boat doesn't know, props 2 feet off centerline on a 14.5 foot beam. In rough water and high winds, the ride is much more comfortable with both engines running.
Edelweiss
Guru
Same here 
There is very little handling difference when the boat is at cruise speed.. Slow speed, close in maneuvering is a different story, both engines running.
40 years ago now, I got in the habit of running on one engine when we cruised with several of my buddies who had single engine Taiwan boats. With both engines running, I was at not much more than a fast idle to avoid running away from them and engine temps were too cold at 140f.
Swapping engines every hour or so kept the engines at operating temp and hour meters equal, plus the boat was much quieter. If we're slow cruising or fishing, we still often run on one engine. I have the original BW Velvet Drives, which have never been out of the boat.
No idea if there is any fuel savings and still do the maintenance the same regardless of hours.
There is very little handling difference when the boat is at cruise speed.. Slow speed, close in maneuvering is a different story, both engines running.
40 years ago now, I got in the habit of running on one engine when we cruised with several of my buddies who had single engine Taiwan boats. With both engines running, I was at not much more than a fast idle to avoid running away from them and engine temps were too cold at 140f.
Swapping engines every hour or so kept the engines at operating temp and hour meters equal, plus the boat was much quieter. If we're slow cruising or fishing, we still often run on one engine. I have the original BW Velvet Drives, which have never been out of the boat.
No idea if there is any fuel savings and still do the maintenance the same regardless of hours.
sunchaser
Guru
- Joined
- Apr 9, 2008
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- sunchaser V
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- DeFever 48 (sold)
There is an active thread on boat diesel about a fellow who was operating on one engine due to a locked transmission. When transmission repaired the engine would not turn over, water locked and destroyed.
go to that site for details if you are interested.
Also, operating on one engine may present battery issues with the down engine's alternator off line.
So many reason to be careful here, seems hardly worth it to intentionally operate on only one unless you've got the right setup and knowledge.
go to that site for details if you are interested.
Also, operating on one engine may present battery issues with the down engine's alternator off line.
So many reason to be careful here, seems hardly worth it to intentionally operate on only one unless you've got the right setup and knowledge.
C lectric
Guru
I'm sure the run has or has not been made since this thread started months ago. Hopefully successfully.
The manual that was posted was a generic T.D. manual, not specific to a model. My 506 manual says secure the shaft, do not freewheel.
You need the specific manual to really know.
The O.P. did due diligence by calling and talking to T.D., good for him.
For those that have to secure the shaft a pipe wrench will work but it may have to be mounted upside down. Use several Tyraps to secure the wrench. I would do that regardless even if the wrench sat on top.
I also use a small plywood pad under the handle to protect the hull. Don't really think it's needed but better safe than sorry.
And Sunchaser has a good point that you need to KNOW more than just the gear recommendations. This poor guy backfilled the shutdown engine. Won't know exactly why for a while but it could have been the exhaust system, or the cross connected dripless shaft seals, or, or.
Be CAREFULL.
The manual that was posted was a generic T.D. manual, not specific to a model. My 506 manual says secure the shaft, do not freewheel.
You need the specific manual to really know.
The O.P. did due diligence by calling and talking to T.D., good for him.
For those that have to secure the shaft a pipe wrench will work but it may have to be mounted upside down. Use several Tyraps to secure the wrench. I would do that regardless even if the wrench sat on top.
I also use a small plywood pad under the handle to protect the hull. Don't really think it's needed but better safe than sorry.
And Sunchaser has a good point that you need to KNOW more than just the gear recommendations. This poor guy backfilled the shutdown engine. Won't know exactly why for a while but it could have been the exhaust system, or the cross connected dripless shaft seals, or, or.
Be CAREFULL.
