anodes

[isha]

Have replaced external anodes on my Yamaha 75 HP 2 stroke engine of 2006 vintage but cannot see how to replace those in the block. Can anyone advise please.
Dave

 

[rbcoomer]

Have replaced external anodes on my Yamaha 75 HP 2 stroke engine of 2006 vintage but cannot see how to replace those in the block. Can anyone advise please.
Dave

Hi Dave,

No replies yet, so thought I'd have a look!

If I have the right motor, it would appear it's part number 9 and is under the crankcase cover (part 18). Is it something that requires routine replacement however or just when significantly erroded? I'd guess that it's only affected when engine is actually running and thus would survive a considerable number of hours between replacements?

http://www.boats.net/parts/search/Y... Later/F75TLR/CYLINDER CRANKCASE 2/parts.html

Do you have a service manual? I wonder if it's possible to find out the recommended replacement interval....

Best regards,

Robin

 

[isha]

Hi Robin
Having since sought advice from a Yamaha service and sales business it appears that the cylinder head has to be removed to get to the internal anodes. The service manual which they showed to me made no reference to renewing these anodes, yet it shows them in a diagram.
The users manual mentions that they should be replaced after 5 years and to see a service agent. I think I shall just use the engine and continue to give it a really extensive flushing out when winterising. I only run the engine for approx 40 hours each season.
Thanks for your reply.
Dave

 

[Spi D]

Yamaha are generous with manuals but when looking at their library there is no such thing as a 2-stroke 75 hp in 2006 - only from 1994 to 2000.
Your engine number would show.

http://yamahaoutboards.com/owner-resources/owners-manuals


Might be this one
http://www.yamaha-motor.com/assets/service/manuals/1998/lit-18626-02-99_647.pdf

 

[rbcoomer]

Hi Robin
Having since sought advice from a Yamaha service and sales business it appears that the cylinder head has to be removed to get to the internal anodes. The service manual which they showed to me made no reference to renewing these anodes, yet it shows them in a diagram.
The users manual mentions that they should be replaced after 5 years and to see a service agent. I think I shall just use the engine and continue to give it a really extensive flushing out when winterising. I only run the engine for approx 40 hours each season.
Thanks for your reply.
Dave

Hi Dave,

Wow that's an interesting revelation! I could envisage a bolt into the block or head as it would need to connect to the water channel to have any effect, but to have to remove the head to change an anode seems a bit drastic. I think I'd probably do the same as you but it would be interesting to know what condition they'd typically be in after 5 years. The only concern is if it were to become brittle and bits break away - where would they go and what could they block? I'd certainly be more cautious with an engine that lived in the water, but if you're running limited hours and flushing then it does seem unlikely that it would be badly dissolved.

Perhaps someone who routinely services these engines will spot the thread and comment. Good luck with it anyway!

Best regards,

Robin

 

[isha]

Hi Spi D
It is a 75 CETO long shaft 2 stroke with 3 cylinders. The same block as the 90 hp version and in all probability was an ex RNLI engine A Yamaha agent looked up the serial number and it does exist but the strange thing is that whilst the service manual shows an exploded engine block diagram with the anodes there is no mention of them or of changing them in the same manual. Yet in the users manual it mentions that they should be changed every 5 years by an authorised service agent.
I have decided to ignore them as I only use the engine for about 40 hrs each summer and give it a really good flush when winterising.