volvo 2030 anode connection

[Bosun Higgs]

My boat is out of the water and a check on the resistance between the hull anode and the prop showed a high 15 ohms. Investigateion revelaed that the resistance was between the gearbox bolts where the anode connection is and the gearbox output flange ie across the gearbox bearings etc.

OK so far. But this engine has the gearbox insulated from the engine block with dire warnings of what will happen if you bridge this insulation. So there is no alternative connection point for the wire running to the anoide but through the gearbox. And 15 ohms is far too much.

Has anyone else come across this problem? Anyone got a connection at a different point? I cannot use a shaft anode as my shaft is too short to accommodate one.

 

[VicS]

I thought the insulation of the gearbox only applied to saildrives!
However even if the gear box was not insulated you'd probably have the same problem .

An "Electro eliminator" http://www.mgduff.co.uk/mgduff-product-catalog/Electro+Eliminators/ to make direct contact with the shaft may be the solution

 

[SvenglishTommy]

The MD20xx range does insulate the gearbox from the block. I had it pulled up as an issue on a survey because the surveyor didn't know this. You really dont have enough space for a small annode? You can get pretty skinny ones. My new boat which has a 2030 also has an annode that screws on after the prop, any spare thread after the prop on yours?

 

[pvb]

The MD20xx range does insulate the gearbox from the block.

The B and C versions of the engines do; the earlier A versions used an earthing relay.

I don't think the OP should have a hull anode connected to the gearbox at all. I'd consider a prop anode to be sufficient.

 

[Ruffles]

I don't think the OP should have a hull anode connected to the gearbox at all. I'd consider a prop anode to be sufficient.

Our MD2030 hasn't had a shaft anode in the 12 years I've owned it. The gearbox is connected to a hull anode. Prop is as sound as a bell. And is probably original to the boat.

 

[VicS]

Our MD2030 hasn't had a shaft anode in the 12 years I've owned it. The gearbox is connected to a hull anode. Prop is as sound as a bell. And is probably original to the boat.

The Westerly I used to sail has no anodes at all.
The prop is original and as sound as a bell. The boat is now approx 34 years old!

 

[pvb]

Our MD2030 hasn't had a shaft anode in the 12 years I've owned it. The gearbox is connected to a hull anode. Prop is as sound as a bell. And is probably original to the boat.

And is your 2030 an A, B or C version?

 

[Ruffles]

The Westerly I used to sail has no anodes at all.
The prop is original and as sound as a bell. The boat is now approx 34 years old!

I'd miss not having an anode to replace. It's the last job before you put the boat back in the water.