Who's eaten the prop blades?

[Daydream believer]

To be honest i cannot see how the saildrive can be isolated from the enginie
The housing on my MD 20 20 is bolted irect to the engine & the drive shaft connects directly to the engine
The whole assembly inside the drive is bathed in oil
There are no plastic or rubber parts between saildrive & engine
I do accept that you have said SOME saildrives are isolated but i might feel disinclined to believe that
On a slightly different note
When i changed from an aluminium fixed prop to a brunton prop my anode useage went from never needing changing to just about survives a season
So that is not isolated - i would assume!!

 

[VicS]

To be honest i cannot see how the saildrive can be isolated from the enginie
The housing on my MD 20 20 is bolted irect to the engine & the drive shaft connects directly to the engine
The whole assembly inside the drive is bathed in oil
There are no plastic or rubber parts between saildrive & engine
I do accept that you have said SOME saildrives are isolated but i might feel disinclined to believe that
On a slightly different note
When i changed from an aluminium fixed prop to a brunton prop my anode useage went from never needing changing to just about survives a season
So that is not isolated - i would assume!!

Yours must be an "A" version of the MD2020.

the insulation is found on the MD2020B and later versions.

There is an insulating plate between the two halves of the flywheel housing. The bolts between the two halves are fitted with insulating bushes and washers.

The drive drain is insulated by an insulating flexible coupling.

The owners manuals refer to the insulation of the saildrive from the engine.

Cannot comment on your Brutons Prop. Yanmar do I believe stipulate insulated props when fitting folders or other bronze props in place of the aluminium prop. I must have read something in the manual that Vyv provided a link to.
Take care never to allow your saildrive anode to become completely depleted . If it does the saildrive leg itself will follow

 

[Daydream believer]

Yours must be an "A" version of the MD2020.

the insulation is found on the MD2020B and later versions.

There is an insulating plate between the two halves of the flywheel housing. The bolts between the two halves are fitted with insulating bushes and washers.

The drive drain is insulated by an insulating flexible coupling.

The owners manuals refer to the insulation of the saildrive from the engine.

Cannot comment on your Brutons Prop. Yanmar do I believe stipulate insulated props when fitting folders or other bronze props in place of the aluminium prop. I must have read something in the manual that Vyv provided a link to.
Take care never to allow your saildrive anode to become completely depleted . If it does the saildrive leg itself will follow

Mine is a D

 

[vyv_cox]

To be honest i cannot see how the saildrive can be isolated from the enginie
The housing on my MD 20 20 is bolted irect to the engine & the drive shaft connects directly to the engine
The whole assembly inside the drive is bathed in oil
There are no plastic or rubber parts between saildrive & engine
I do accept that you have said SOME saildrives are isolated but i might feel disinclined to believe that
On a slightly different note
When i changed from an aluminium fixed prop to a brunton prop my anode useage went from never needing changing to just about survives a season
So that is not isolated - i would assume!!

I suggest you read this thread. Lots of info, photos and links explaining which saildrives are isolated, how they vary, which engines, etc.

http://www.ybw.com/forums/showthread.php?343853-Volvo-Penta-Saildrive-isolation-how

 

[VicS]

Mine is a D

In which case in the diag below #28 is the insulating plate and #30 and #31 are the insulating bushes and washers on the bolts

and #33 is the flexible coupling: