Prolonged Operation in Reverse Gear

[StringBimini]

This may be a stupid question, but here goes. My boat has an old diesel, a Volvo MD11C, with a Walter v-drive. The boat is under repair and can't be sailed at present, however, I wanted to get some run time on the diesel under load. My bad, but I hadn't started the diesel in about 6 months.

So...I started her up (first try! I was happy), and after a 10-min warmup at 800-900 rpm, and with the boat tied off to the dock, I shifted it into reverse. I should note that I am located in the gulf coast, so the weather is warm here (like 70 deg-F). I allowed the docklines to become taunt, then slowly increased the speed to 1300-1400 rpm. Then, I let it run for an hour. Water temperature came up, but well within normal. I wanted the temp up, to vaporize any water that may have accumulated in the oil. Oil was fresh, with less than one hour run time on the oil.

So...could I do any damage to the engine, or the drive system, when operating in this way?

Don't worry about the dock...it was well secured

Let me know what you think.

[boatman61]

I doubt it.... else they wouldn't fit a reverse gear...

[sailvayu]

The Volvo transmissions use a cone clutch so it is about the same forward or reverse. The vee drive will take the thrust and should be ok but why not run it in forward?

[StringBimini]

I felt it was safer in reverse, if one of the docklines let go. As unlikely as that was, I chose to go in the safe direction.

[boden36]

You may find that the helical shaft in the gearbox is retained with a circlip that takes reverse thrust, but forward thrust is taken by a more substatntial bearing.
Regards, Richard.

[goboatingnow]

Would agree run in forward direction. This is the way the gearbox was designed to run.

Dave

[Springbok]

With the engine in reverse the fuel will return to the fuel tank so you can run it for hours with no consumption Have a good New Year. If you circumnavigate in reverse gear will never have to refill fuel tank and you will stay under that dreaded $500/mnth limit
Clyde

[James S]

I do the same during the winter...I run a bit in forward, but mostly in reverse.
My thought, ridicules as it may be, is that in reverse I may blow off some of the bottom growth.

[swagman]

We had pals who blew a forward gear near St Malo, France after a race from the UK.

With no winds next day it was 80 miles home in reverse the whole way..............so I do not think one hour at a dock would be an issue.

JOHN