Trailing gearbox while sailing

[Alan Wheeler]

I can remember we talked about this issue sometime back, but I couldn't find it anywhere. So I thought I would start a new thread. I do remember we were unsure if a type of gear box could be left in gear or not when engine was not running and the boat was undersail. Well, this may still not actually give an answer for what ever the particular box in question, but it may help others. I found this info in the back of my Perkins manual.

Gearbox type: Max time trailed: Conditions:
Selfchanging Gears Ltd. 12hrs None
Thames Marine Propulsion 8hrs None
Parsons Mechanical Gearbox Indefinitely If Oil kept at top mark
Twin Disc Marine gears 8hrs None
Paragon Mechanical Gearbox Indefinitely If oil kept at top mark
Borg Warner 8hrs Providing rotational
speed in 'forward'
and 'Reverse' part of
gearbox does not
exceed 1500RPM.
That is max propelled
shaft speed of:
Direct Drive: 1500RPM
1.5:1 1000RPM
1.9:1 790RPM
2.1:1 715RPM
2.5:1 600RPM
2.9:1 520RPM

Hope this is of some interest to someone.

[Alan Wheeler]

Awwe, shoot. I had that all laid out nicely, but the software has rearranged it all. Oh well, I nhope you can all understand it.

Re: the Borg Warner, I had concerns about this issue when a shop was trying to sell me one. The older manual states a max of 8 hours trailing in nuetral. I called Borg Warner, and they state that that guideline no longer applies. I am still skeptical, but that is their stance on the issue.

[Alan Wheeler]

So did they have a recomendation of what to do at all??

THey said let it freewheel. No damage will occur. They did acknowledge that the recommendation had changed. I personally do not trust this recommendation, and lock my shaft. I installed an eye bolt on the coupler so I can run a cable to the stringer when under sail. Have not forgotten it yet, but....
I could not find the recommendation in the Brog Warner manual from 1986, but it did say to refer to the OEM manual. THe Manual for my challenger from 1974 states "run the engine for 15 minutes for every 8 hours of freewheeling the prop"