Stainless water pipes why not?

Post by **waltraud** » 22 Oct 2008, 20:17

Hi- been thinking about changing my old & worn back to front pipes on DG to plastic but someone said he found that the metal inserts in the ends rusted & caused probs so he got SS ones from Germany -scuse the pun. Is there a reason why this is or not a good idea apart from price? thanks. Tim

Post by **jason k** » 22 Oct 2008, 21:28

because of the electrolytic corrosion caused when stainless meets ally .
the two metals eat each other.

Post by **Mr Bean** » 22 Oct 2008, 22:14

jason k wrote:because of the electrolytic corrosion caused when stainless meets ally .
the two metals eat each other.

Yes in naughty aerospace Stainless Steel has to be cad plated for that reason.
But as Cadmium is harmfull to the environment it can't be used any more.

Funny world init!:lol:
Cheers
Smiffy

Post by **jaylo264** » 22 Oct 2008, 22:28

I `ve got stainless inserts in the ends of me plastic pipes and they aren`t at all corroded--maybe the ally is acting as a cathode ?

jaylo

Post by **waltraud** » 23 Oct 2008, 07:11

Cheers folks- is diesel eng' also ally head?....Anyhow, In that case as u say I should probably buy the plastic ones off a bloke I know who's machined ally inserts BUT his is Jx engine- Q- are there different types/sizes of plastic pipe? thanks T

Post by **toomanytoys** » 23 Oct 2008, 07:45

Its normally just a problem when alloy and stainless are actually touching...

there are many different types of metal in the cooling system already.. iron, steel, alloy, copper, brass.. fitting a set of front to backs in stainless prob wont see any more effect than already in there....

Post by **Mr Bean** » 23 Oct 2008, 08:21

toomanytoys wrote:Its normally just a problem when alloy and stainless are actually touching...

there are many different types of metal in the cooling system already.. iron, steel, alloy, copper, brass.. fitting a set of front to backs in stainless prob wont see any more effect than already in there....

very true actually and when you consider that even the cheapest antifreeze claims to have corrosion reduction capability the risk is minimal compared to the problems largely due to heat at the exhaust/cylinder head fixings.
And of course scientists and less worldly people do tend to read these reports far too literally.
Cheers
Smiffy

Post by **dugcati** » 23 Oct 2008, 08:51

I don't understand where this conversation is going as the hoses are clamped at each end onto rubber hoses is it not?

Post by **HarryMann** » 23 Oct 2008, 09:13

I think the suggestion is that wherever they are in the system, the coolant acts as an intermediary in the way of an electrolyte...

I don't think this is particularly a problem either, esp. as Citizen Smiff says, 50/50 antifreeze/water.

You'll probably find about 10 pages of discussion of this on the US SubaruVanagon yahoo list, and like as not with no firm opnion at the end either