Zinc nut size yanmar 2gm 80's model

[steveinusa]

This was posted a while back but i didn't see a real answer niow I' m faced with the same thing and I have the shop manual but it doesn't even specify the outside plug nut size and sae or metric for my 80's model Yanmar 2gm. i don't want to buy the wrong socket at sears coz its $$. Appears to be a 1" or 1 1/16"?. Thanks for help!

 

[Charles Erwin]

Steve

Get an open ended adjustable (crescent) wrench, adjust it until it just fits the nut in question, remove the wrench then measure the gap between the two jaws.

And now that you know this trick your can help someone else sometime.

Charles

 

[Ron20324]

??? I don't see the "real question". Do you mean the nut at the end of the shaft?

 

[steveinusa]

??? I don't see the "real question". Do you mean the nut at the end of the shaft?

The large plug, nut size on outside of engine block. Its big. About an inch or so.
Thanks...

 

[steveinusa]

Good idea Charles... I didn even think of that! I'll give it a shot.

 

[woodster]

isn't that a sq nut ...if so make sure you get an 8 point socket

 

[Charles Erwin]

Woodster

6 or 12 point (I like 6 every time can use it) on this Yanmar zinc plug.

Charles

 

[woodster]

Woodster

6 or 12 point (I like 6 every time can use it) on this Yanmar zinc plug.

Charles

Charles thats fine on a hex nut or bolt...... but on a sq nut or bolt 8 point ..

 

[Charles Erwin]

You are right

I confine my statement exclusively to Yanmar motor zinc holders. Yanmar is always 6 point on these zinc holder fittings.

I express no opinion why this is so.

Charles

 

[woodster]

on the qm series they are sq head is why i stated the 8 point ...same as the winch handles are 4 point going in to a 8 point socket ...i agree with the 6 and 12 on a hex nut

 

[SailingaS2]

I just replaced my zincs on my 1981 2GM this fall and it's a 1 1/16 square so I bought an 8 pt. socket from my Matco tool dealer
I don't think the rear one was touched after it left the factory , had to use a breaker bar with an extension
Tom

 

[steveinusa]

I just replaced my zincs on my 1981 2GM this fall and it's a 1 1/16 square so I bought an 8 pt. socket from my Matco tool dealer
I don't think the rear one was touched after it left the factory , had to use a breaker bar with an extension
Tom

Yea!!
thanks Tom. exactly the info I was looking for! A marina guy told that i'd probably need a big driver and cheater bar too. Awesome info. Thanks again.
Steve

 

[pateco]

I just replaced my zincs on my 1981 2GM this fall and it's a 1 1/16 square so I bought an 8 pt. socket from my Matco tool dealer
I don't think the rear one was touched after it left the factory , had to use a breaker bar with an extension
Tom

Thank you so much SailingS2.

Now, what would you do if there is not enough space inside the engine bay to use a breaker bar.

I have thought about an impact wrench with wobble head extensions to reach these nuts.
or
I am going to have to cut access holes in the cabinet and bulkhead casework in both the galley and quarter berth to line up with these nuts so that I can use extensions to reach the nuts.