Yanma GM20 Jammed anodes

It's not just the 24mm metric ring spanner, its the 16 oz imperial hammer you tap it with to shock it into moving. And I still have not managed to crack the block.
 
Last edited by VicS; Today at 08:46

Was 'full' the edited version?

No, I dont think so, but exactly what I was editing at 8.45 this morning I don't remember

Surely though," Read the full manual," is what RTFM stands for. At least the Deputy Head of the school where I worked always advised exam candidates to RTFQ, which he explained meant "read the full question"

'fraid I have spent practically the whole day in Maidstone hospital so now almost totally brain dead.
 
Not Yanmar though, no anodes in the 'F' models.

Although there is an anode shown at the end of this link Vyv - http://psyberspace.com.au/yanmar/anatomy.htm

Although perhaps you are counting that as a saildrive anode rather than a 3YM30F anode?

Incidentally, why does it say on it "Don't remove while boat in water"? Presumably the anode sticks into the sea water stream which comes up through the saildrive leg and is presumably before the seacock otherwise you could just close the seacock to change it. I wonder why they didn't put the anode after the seacock?

I haven't changed mine myself yet although I will do it next time.

Richard
 
It's not just the 24mm metric ring spanner, its the 16 oz imperial hammer you tap it with to shock it into moving. And I still have not managed to crack the block.

I use a 24mm socket - and 2 extension breaker bars. Still needs a good heave to loosen, but it does work. My 3gm30 is raw water, so I do this with the seacock shut. There is still a fair dribble out the aperture, but it's easily mopped up. Even if converted to fresh water - I would see little harm in leaving them working?
 
Surely though," Read the full manual," is what RTFM stands for.

Wow, seriously?

Sorry to disillusion you, but it actually stands for "Read The Fucking Manual". Crusty old engineer's response to being asked a basic question that is already answered in the docs. Various bowdlerised versions exist, but I always assumed the people using them were aware of the original and were just being polite.

Pete
 
Although there is an anode shown at the end of this link Vyv - http://psyberspace.com.au/yanmar/anatomy.htm

Although perhaps you are counting that as a saildrive anode rather than a 3YM30F anode?

Incidentally, why does it say on it "Don't remove while boat in water"? Presumably the anode sticks into the sea water stream which comes up through the saildrive leg and is presumably before the seacock otherwise you could just close the seacock to change it. I wonder why they didn't put the anode after the seacock?

I haven't changed mine myself yet although I will do it next time.

Richard

My reply to VicS' post was referring to the heat exchanger. All the anodes shown in the link (quite a good one, incidentally) are on the saildrive, not the engine. I cannot answer your question, I have a shaft drive and have not really studied saildrives other than about their corrosion.
 
Although there is an anode shown at the end of this link Vyv - http://psyberspace.com.au/yanmar/anatomy.htm

Although perhaps you are counting that as a saildrive anode rather than a 3YM30F anode?

Incidentally, why does it say on it "Don't remove while boat in water"? Presumably the anode sticks into the sea water stream which comes up through the saildrive leg and is presumably before the seacock otherwise you could just close the seacock to change it. I wonder why they didn't put the anode after the seacock?

I haven't changed mine myself yet although I will do it next time.

Richard

My reply to VicS' post was referring to the heat exchanger. All the anodes shown in the link (quite a good one, incidentally) are on the saildrive, not the engine. I cannot answer your question, I have a shaft drive and have not really studied saildrives other than about their corrosion.

I guess the warning is because if that anode is removed while the boat is afloat water will come flooding in.

It is presumably in the top pat of the sail drive leg to protect that . All there is after the seacock is the rubber hose leading to the seawater pump. Rubber hoses do not require protection by anodes.
 
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Have the same issues with my Yanmar, the one of the side it not too bad but removing the anode at the rear is always a struggle. A well fitting long spanner and a moderate wack with a hammer normally gets it freed off. I grease it every year but it's always a sod to undo.

Good luck
 
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