Stopping shaft from turning after loss of an engine

Hi,

There are a number of pre engineered ways to overcome this problem but the OP's original question was how to do it when an un expected failure makes you run on one engine to get home.

Are you saying that the moment the engine kicks off unexpectedly while in gear (and maybe in reverse gear at that) that your gear box is then in a free wheel neutral setting? And I am talking about the larger gear boxes you find on 40 50 M vessels, I don't know about the smaller ones on smaller sail boats and such.
Also maybe the engine can still be started but has a cooling issue or something keeping it from long term use.

Hi,

The next time you start one of your main engines have a look at the gearoil pressure gauge. If you cannot see it from where you start the engine get the 2nd Engineer or someone else to help you. You will see that the clutch oil pressure comes up to somewhere around 21-15 Bar (300-350 psi) it can sometimes take a couple of seconds and should be fairly steady, stop the engine and you will see it drop down.

It will also drop a bit just as the clutch pack becomes pressurized ( engaged)

Precisely, you need the psi to go in/out of gear. But now you are saying that the moment you loose the PSI (because the engine quit) you will no longer be in gear and you will free wheel?

When you say "cooling the shaft" are you referring to the shaft packing gland or the transmission?

Yes, on the yachts I have run when the engine shuts off and the flywheel stops turning on the engine, the gear will lose gear oil PSI and the gear will then lose the amount of PSI needed for the clutches to stay locked into gear. On a ZF transmission, it needs 75 PSI minimum to stay in gear.

The OP's scenario was how to get home in case of emergency... and this thread has blown right past the obvious Clue... I say it's Mr. Schweizer, in the engine room, with the monkey wrench.

He must be referring shaft packing gland, i don't have any clue how he can cool transmission using a line from washdown pump. However my question is can it help in long run?

Hi,

Read the Original Post: http://www.yachtforums.com/forums/133589-post1.html

It is not a stuffing box with Packing Gland he is asking about.

Last week I was headed from Fort Lauderdale to the Port of Palm Beach to load a 55' motoryacht on a freighter to Australia. One engine overheated, no tools on board, no monkey wrenches in the galley, but I had to get the boat to the ship in time. The new owner risked losing his very substantial fee paid to ship all the way to Australia. Most shipping companies will not refund if you do not get there in time, not their fault.
I wrapped a one inch nylon dock line around the shaft at least four times after putting the eye on an engine mount. The line held just like on a winch. The boat did have crossover cooling from one stuffing box to the other, but I was concerned with overheating the reverse gear.
We got to the ship in time....