Prop Windmilling ???

[Bob Luby]

Took out my CD25d today - and noticed my prop has started windmilling.
i.e. Saiing with the engine off,& transmission in neutral results in a noise. The noise is reduced when I put the trans in forward gear, and eliminated when I put the trans in reverse.

Does this indicate other problems to come? (Before last season I had
a PYI Shaft seal and new cutlass bearing installed.) or is this this just normal behavior?

The engine is a Yanmar 1GM10.



Rluby@aol.com

[Richard Feffer]

Bob,
You might try putting the transmission control lever in reverse when under way. The noise is coming from the prop turning when boat is making forward progress. I believe Yanmar recommends stoping the shaft because the transmission is not getting proper lubrication if the engine is not running. Should solve the problem.
Good luck.

Took out my CD25d today - and noticed my prop has started windmilling.
i.e. Saiing with the engine off,& transmission in neutral results in a noise. The noise is reduced when I put the trans in forward gear, and eliminated when I put the trans in reverse.

Does this indicate other problems to come? (Before last season I had
a PYI Shaft seal and new cutlass bearing installed.) or is this this just normal behavior?

The engine is a Yanmar 1GM10.

RichFef@Prodigy.net

[Bill]

>The noise is reduced when I put the trans in forward gear, and eliminated when I put the trans in reverse.

Hi Bob

My owners manual says to sail with the tranmission in reverse!

Bill



cd25d@rhapsodysails.com

[Chris Reinke (CD330 Innis]

Bob - It does not sound as though you have a major problem at this time. The sound created from the freewheeling shaft may be a bit of an annoyance but it does not sound as though you have a mechanical problem. I would suggest you try and spin the shaft by hand (motor off) and note any resistance.

When I received my new Hurth transmission earlier this year (another story in itself) the new one had a very large tag on it which stated that the transmission should be in either neutral or reverse while sailing - NEVER IN FORWARD. I have complied with this notice as I have no knowledge of the mechanical arguments for or against it. Several folks have indicated in past postings that sailing with the transmission in neutral reduces drag. Other have indicated that bearing wear is occurring while the shaft is free spinning. I guess the choice is up to the individual owner. I have personally never considered speed a major priority other wise I would own a CD 28 powerboat.

Took out my CD25d today - and noticed my prop has started windmilling.
i.e. Saiing with the engine off,& transmission in neutral results in a noise. The noise is reduced when I put the trans in forward gear, and eliminated when I put the trans in reverse.

Does this indicate other problems to come? (Before last season I had
a PYI Shaft seal and new cutlass bearing installed.) or is this this just normal behavior?

The engine is a Yanmar 1GM10.

chris.reinke@transamerica.com

[Bob Luby]

My owners manual says to sail with the tranmission in reverse!

OK! I guess from now on I sail with the gearshift in reverse!

Thanks - folks!



Rluby@aol.com