Painting Yanmar saildrive

[janis]

My saildrive paint is in bad condition and I plan to repaint it with epoxy paint. What should I do in terms of painting with surface close to saildrive anode? See area marked with green in picture. Should I paint it or keep bare metal? Anode screws should provide some electrical connection between anode and saildrive or extra unpainted surface is needed?

[fstbttms]

Do not paint it

[GordMay]

Originally Posted by fstbttms

Do not paint it

The Operation Manual* has 'basic' painting instructions, on page 17:
* UNDERWATER DRIVE COATING ➥ https://www.yanmar.com/media/global/...OM_27MAR09.pdf

[fstbttms]

Originally Posted by GordMay

The Operation Manual* has 'basic' painting instructions, on page 17:
* UNDERWATER DRIVE COATING ➥ https://www.yanmar.com/media/global/...OM_27MAR09.pdf

Page 17 has prop installation instructions. And I find nothing anywhere regarding painting the the leg under where the anode is fitted.

[Tin Tin]

Originally Posted by fstbttms

Page 17 has prop installation instructions. And I find nothing anywhere regarding painting the the leg under where the anode is fitted.

That would be found under the "other" category as specified by the Anode manufacturer on p 13

[FlyingScot]

I definitely would NOT paint that. You want the contact betweent the anode and the drive leg.

[more]

Originally Posted by janis

My saildrive paint is in bad condition and I plan to repaint it with epoxy paint. What should I do in terms of painting with surface close to saildrive anode? See area marked with green in picture. Should I paint it or keep bare metal? Anode screws should provide some electrical connection between anode and saildrive or extra unpainted surface is needed?

yes paint this,dont paint zinc anode.
i use after remove paint to bare metal Hempel Prop Primer Grey Spray
this is etching primer. after dry use 800-1000 Waterproof Sandpaper
paint.
only dont paint zinc anode.
after this international epoxy primer. 800-1000 sandpaper 2-3 coat is ok
after this 2-3 coat Trilux 33 and sand paper 1000-2000

after this put good layer white greas on all

any part of saildriv must be good cover, in any part exposed to see water with bare aluminium saildrive be fast destroyed

[fstbttms]

Originally Posted by Tin Tin

That would be found under the "other" category as specified by the Anode manufacturer on p 13

Page 13 says nothing about painting the leg under the anode

[Tin Tin]

Originally Posted by fstbttms

Page 13 says nothing about painting the leg under the anode

No it doesn't.
It says refer to the anode manufacturer. Martyr for example includes instructions on the back of the pack, I don't have one to hand and don't recall what they say.



Most of us know and so do you I am sure, where the anode actually touches the leg (around the bolt holes) should be sanded bare aluminum for best contact with the anode, where the anode does not touch the leg, the leg should be painted. Split ring and full ring anodes fit slightly differently. I am guessing that a brand new SD leg would be a guide, but I don't have one of those to hand either.

[Jon Hacking]

Don't paint that area.

For the anode to work correctly, it has to be in intimate electrical contact with the leg. It gets some of that from the bolts, but it really wants to touch the aluminum leg as much as possible.

Also, why would you want to paint that area?

It's not painted when you get a new SD. And it's not going to grow anything anyway, with the anode bolted to it.

[more]

Originally Posted by Jon Hacking

Don't paint that area.

For the anode to work correctly, it has to be in intimate electrical contact with the leg. It gets some of that from the bolts, but it really wants to touch the aluminum leg as much as possible.

Also, why would you want to paint that area?

It's not painted when you get a new SD. And it's not going to grow anything anyway, with the anode bolted to it.

wrong is painted when is new,also only bolt have conection with zinc anode.
for outboard is best you make no any conection with sea water. for example if sit in garage 100 km from sea is best protection,but sometime we go to sea on this case best paint make barrier between sea and aluminium lower leg.differences between makers, in that Yanmar ones are electrically connected to the rest of the boat, whereas Volvo ones are totally isolated from everything else in most cases.

It is important to preserve the isolation of the Volvo ones, ensuring that no metals can bridge between the leg and the gearbox, and that the gasket is kept clean and dry.

In each case it is important to replace the anode annually, ensuring a good electrical connection on installation.

The paint applied to saildrives is of great importance in reducing the area of the cathode and should also be checked annually.

https://www.yachtingmonthly.com/gear...m-anodes-70157


american boat designer learning from 200 year book,now navy must scrap new aluminium frigate,corvete,patrol boat some transport all new and ready for scrap metal.

we have around 200 aluminium fast taxi boat,best galvanic and paind protection after season drydock. who dont do this boat dont last long. also jet ski almost all after use go in dry dock or pay 2-3000€ aluminium jet part.
aluminium have bad property any scratch from bare metal spread like cancer

[fstbttms]

Originally Posted by more

wrong is painted when is new,also only bolt have conection with zinc anode.

100% wrong. The entire aluminum bolt mounting surface is in contact with the leg.

[GordMay]

Originally Posted by fstbttms

Page 17 has prop installation instructions. And I find nothing anywhere regarding painting the the leg under where the anode is fitted.

Oops, Sorry! As Tin Tin noted, , Page 13.

[janis]

The referenced manual (Page 13) doesn't say much. Just "Never paint over drain holes, sacrificial anodes, or other items specified by the sacrificial anode Manufacturer.". So no mentions about contact areas with anode.

Why I would like to paint maximum amount of surface would be to protect aluminium saildrive surface from corrosion.

This is by the way how old anode looks. So it looks like some areas of anode have disintegrated differently (near screw holes).

[Tin Tin]

Originally Posted by janis

The referenced manual (Page 13) doesn't say much. Just "Never paint over drain holes, sacrificial anodes, or other items specified by the sacrificial anode Manufacturer.". So no mentions about contact areas with anode.

Why I would like to paint maximum amount of surface would be to protect aluminium saildrive surface from corrosion.

This is by the way how old anode looks. So it looks like some areas of anode have disintegrated differently (near screw holes).

Have you got your replacement anode yet?