Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 12-09-2007, 10:02   #1
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
Where the Heck Does the Yanmar Internal Zinc for the Saildrive Go?

I've got a pencil zinc and for the life of me I can't figure out where this thing goes. I looked at the SD manual (SD20 and SD31) and it has a pointer going to a part of the diagram that's not visible. Everything else is visible in the diagram, just not the part I've got in my hand. I looked at the saildrive itself and know it's "opposite the sea valve". If someone has this saildrive, could they please please please post a picture of this Zinc placement?

Also, I guess you're not supposed to replace this while in the water?

Its a zinc, it should be the simplest thing in the world to see and replace. And since I can't see this thing, I imagine one isn't in place right now. It looks like it just screws in somewhere. Since my lower unit Zincs are deteriorating quickly (read gone) I imagine it's more important than ever to get this done quickly. Actually, I imagine someone just put a threaded bolt into the place where the zinc is supposed to go.

27210-200550 saildrive internal zinc anode
__________________

__________________
schoonerdog is offline   Reply With Quote
Old 12-09-2007, 12:08   #2
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
I think I'm tracking down the answer to my own question, there's a large metal blank that I screw this zinc into. Once I remove the blank, water start gushing in, so I work a bit quickly. Assuming I actually unscrew the right piece in the first place. And assuming that my sail drive actually needs one (the local service dealor, bayshore marine in Annapolis said it wasn't needed in the SD31 only the SD20).

"yes honey, there is two feet of water in the boat right now, and no, I really didn't need to pull that plug because it wasn't needed for my unit."
__________________

__________________
schoonerdog is offline   Reply With Quote
Old 12-09-2007, 12:23   #3
Senior Cruiser
 
Vasco's Avatar

Cruisers Forum Supporter

Join Date: Apr 2004
Location: Toronto
Boat: CS36Merlin, "La Belle Aurore" Ben393 "Breathless"
Posts: 7,138
schoonerdog,

My 3GM30F has a large blank in it too, at the back of the engine. It's where zincs used to go but when I checked with Yanmar they said that engine no longer requires pencil zincs. I found the blank because Yanmar had omitted a gasket and it was leaking anti-freeze.
__________________
Rick I
Toronto in summer, Bahamas in winter.
http://groups.yahoo.com/group/beneteau393/
Vasco is offline   Reply With Quote
Old 17-09-2007, 13:30   #4
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
Rick,

Been checking all around now. The pencil zinc goes in the back of the sail drive, under the black M22 hexagonal nut, inside the unit itself. It's function is to protect the sail drive. This is according to Mack Boring, the US distributor, and Bayshore Marine in annapolis, the local service shop reversed themselves and said it wasn't in the parts book though for the SD31. They did recommend pulling it out, looking at the blank and seeing if there was a place for the zinc to go as the extra protection would be a good thing. I guess that's what I'm going to do then...
__________________
schoonerdog is offline   Reply With Quote
Old 17-09-2007, 16:32   #5
Senior Cruiser
 
delmarrey's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Now in Blaine, WA
Boat: Modified Choate 40
Posts: 10,702
Images: 122
One could always bond the saildrive to an external zink located in the area, you think???????
__________________
Faithful are the Wounds of a Friend, but the Kisses of the Enemy are Deceitful! ........
A nation of sheep breeds a government of wolves!

Unprepared boaters, end up as floatsum!.......
delmarrey is offline   Reply With Quote
Old 17-09-2007, 18:13   #6
Registered User

Join Date: Jul 2007
Location: Culpepper, Va
Boat: Shopping for it.
Posts: 77
Not to hijack the thread but I have never had a diesel before..what does the zink do?
__________________
vonotto is offline   Reply With Quote
Old 04-01-2008, 10:34   #7
Registered User
 
Sonosailor's Avatar

Join Date: Mar 2003
Location: Fredericton, NB, Canada in the summer and fall; Caribbean in winter and spring aboard Cat Tales.
Boat: FP Tobago 35 (and a H-21 SE)
Posts: 547
Images: 8
Sacrificial Anodes on 2GM20s

Quote:
Originally Posted by vonotto View Post
Not to hijack the thread but I have never had a diesel before..what does the zink do?
Zinc is attached to submerged aluminum to act as a sacrificial anode. As it is less noble than aluminum (check your old high school chemistry text book. It is quite simple.) it will give up electrons more easilythan the aluminum, and release a zinc ion missing the electron. The energy exchange actually inhibits the corrosion of the aluminum, at least until the zinc is used up.

If you guys are still on this, I have a question: I have two 2GM20s on my cat, with the SD20 saildrives. I have the zinc collar on the saildrives at the prop, and the screw-in anodes inboard behind the big bolt-head. Now, the engines themselves have the same big bolt-heads meant for anodes as well. Do the zincs on the saildrives do enough protection, or should the ones on the engines be worried about as well. In my set-up, they are very difficult to get to.
__________________
Sonosailor is offline   Reply With Quote
Old 04-01-2008, 21:09   #8
Registered User

Join Date: Jan 2007
Location: Fremantle Australia
Boat: Schioning 12.3 "Wilderness" Bi-Rig under construction
Posts: 558
Send a message via Skype™ to Whimsical
I would think the zinc on the motor would be in the fresh water circuit and would help to prevent internal corrosion. Zincs in the seawater would not perform this function.

Mike
__________________
Whimsical is offline   Reply With Quote
Old 05-01-2008, 08:07   #9
Senior Cruiser
 
schoonerdog's Avatar

Cruisers Forum Supporter

Join Date: May 2004
Location: annapolis
Boat: st francis 44 mk II catamaran
Posts: 1,174
Images: 4
Mike,

I think you are right. on the 3JH series there are no engine zincs, but I believe the GM needs them.

Doug
__________________
schoonerdog is offline   Reply With Quote
Old 05-01-2008, 10:21   #10
Senior Cruiser

Cruisers Forum Supporter

Join Date: Dec 2006
Location: Seattle
Boat: Cal 40
Posts: 2,401
Images: 7
This thread has drifted from the original saildrive question. I've come up against this before as I own a 3GM30F(non saildrive). I've found the Yanmar Marine Engine Help site to have usefull information. It is run by a Yanmar shop in the UK.

Non saildrive answer:

Yanmarhelp.com Message Forum - Yanmar marine diesel engine help & advice -> 3GM30F zinc anodes?

John
__________________
cal40john is online now   Reply With Quote
Old 12-01-2008, 12:33   #11
Registered User
 
Sonosailor's Avatar

Join Date: Mar 2003
Location: Fredericton, NB, Canada in the summer and fall; Caribbean in winter and spring aboard Cat Tales.
Boat: FP Tobago 35 (and a H-21 SE)
Posts: 547
Images: 8
Replacing an SD20 anode bolt with boat in water

Quote:
Originally Posted by schoonerdog View Post
I think I'm tracking down the answer to my own question, there's a large metal blank that I screw this zinc into. Once I remove the blank, water start gushing in, so I work a bit quickly. Assuming I actually unscrew the right piece in the first place. And assuming that my sail drive actually needs one (the local service dealor, bayshore marine in Annapolis said it wasn't needed in the SD31 only the SD20).

"yes honey, there is two feet of water in the boat right now, and no, I really didn't need to pull that plug because it wasn't needed for my unit."
With a wine cork at the ready, the anode can be replaced with the boat in the water. The water pressure is't that high. If you're fast, and use the wine cork while you're replacing the anode on the blank, you can replace the anode with much less than a litre of water into the bilge.
__________________
Sonosailor is offline   Reply With Quote
Old 22-01-2010, 22:48   #12
Registered User

Join Date: Jan 2010
Location: Victoria. BC. Canada
Posts: 1
Saildrive 31

Anyone know what size the zinc for saildrive 31 is or part #....?
__________________
Tony Cain is offline   Reply With Quote
Old 22-01-2010, 22:59   #13
Registered User
 
paradix's Avatar

Join Date: Oct 2009
Location: Australasia
Posts: 284
If you mean the internal pencil zinc, the part number is in post number 1 on this thread: 27210-200550

If you mean the external one for the prop, it's 196420-02652
__________________
paradix is offline   Reply With Quote
Old 08-07-2017, 11:48   #14
Registered User
 
masterov's Avatar

Join Date: Dec 2016
Posts: 38
Re: Where the Heck Does the Yanmar Internal Zinc for the Saildrive Go?

I believe this is where the zinc goes:

Click image for larger version

Name:	zinc.jpg
Views:	66
Size:	171.6 KB
ID:	151465

Does anyone have any tips for replacing it while the boat is in the water? Do you think diving under, and covering the intake with a plastic bag will prevent the water from gushing in?
__________________
masterov is offline   Reply With Quote
Old 11-07-2017, 16:59   #15
Registered User

Join Date: Mar 2009
Location: Southern Chesapeake Bay
Boat: Norseman 430, Jabberwock
Posts: 691
Re: Where the Heck Does the Yanmar Internal Zinc for the Saildrive Go?

I bought an extra threaded plug so if I needed to I could pop out the old one and pop the new one in.

Quote:
Originally Posted by masterov View Post
I believe this is where the zinc goes:

Attachment 151465

Does anyone have any tips for replacing it while the boat is in the water? Do you think diving under, and covering the intake with a plastic bag will prevent the water from gushing in?
__________________

__________________
ggray is offline   Reply With Quote
Reply

Tags
saildrive, yanmar

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Yanmar Saildrive Leak captjohn360 Multihull Sailboats 7 23-10-2017 22:22
What Oil for Yanmar (SD 20) Saildrive ? svstrider Engines and Propulsion Systems 7 23-01-2010 06:39
Yanmar SD 20 Saildrive Seals Bonaire Propellers & Drive Systems 12 11-01-2010 15:46
Best Prop for Yanmar with SD 31 Saildrive? quartersplash Engines and Propulsion Systems 2 07-06-2009 21:06
Yanmar 2qm15 zinc anodes Jack Long Engines and Propulsion Systems 2 01-10-2008 06:52



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 20:05.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.