Sabb 2HG Core Plug

[Liam]

Topic title says it all really. I have a Sabb 2HG with a bust core plug which needs replacing. I have the manual which states it as 38mm. A quick search online shows many sources, but also differing materials.

 

This Sabb only has one core plug which makes things easier but there are options for brass, zinc, stainless steel etc. Which is the better material to use?

 

Edited to add... its closed circuit cooling if that makes a difference?

 

Thanks in advance 

Edited May 28, 2021 by Liam

[Tracy D'arth]

If its raw water cooled, go for brass or stainless. Else steel will be OK. I don't understand why there are zinc ones, zinc is usually used as a wasting sacrificial anode in raw water cooled engines.

[Tony Brooks]

5 minutes ago, Tracy D'arth said:

If its raw water cooled, go for brass or stainless. Else steel will be OK. I don't understand why there are zinc ones, zinc is usually used as a wasting sacrificial anode in raw water cooled engines.

 

Me neither if it is a core plug as opposed to a Welch plug. I would think zinc was too soft to form a seal when "flattened" in its hole. In fact I think it would be too soft for a Welch plug. I suspect the zinc ones are zinc plated but still can't understand why you would want a sacrificial core plug rather than an easily replaced pencil anode.

[Liam]

Don't quote me on the zinc thing, I was just scrolling through and may have misread it.

 

So, brass or stainless... any benefits or negatives of either? I suppose brass would be softer so maybe achieve a better seal? Also what dealing compound would you suggest if any? Having only an air cooled Lister before, this new fangled technology is all new to me

[Tony Brooks]

2 minutes ago, Liam said:

Don't quote me on the zinc thing, I was just scrolling through and may have misread it.

 

So, brass or stainless... any benefits or negatives of either? I suppose brass would be softer so maybe achieve a better seal? Also what dealing compound would you suggest if any? Having only an air cooled Lister before, this new fangled technology is all new to me

 

Brass might de-zinc itself when in contact with iron/steel giving rise to a failure after  a long time.

[Liam]

Thanks to you both for your help. I will go down the stainless route I think, theres only pennies difference in something that only costs a quid or two anyway.