Tonval thru hull fitting

[IvorClarke]

Just found out that the heads outlet thru hull fitting that I fitted this last winter is Tonval and not bronze as shown in the chandlers catalog and also on the delivery note.
What are the views of the forum with regard to how long it will last without major loss of Zinc? Should I change it this winter or earlier?

 

[VicS]

You would very unlucky for them to fail in one season I would have thought.

You might like to read the MAIB report of the near sinking of the FV Random Harvest a few years ago in which Tonval fittings were partly to blame.

SEE HERE

 

[doug748]

I suspect I have the same problem. Chandlers are so bloody shifty, when you try to pin them down on what these things are made of. To be fair I am sure they just don't know; so I guess that means: Fear the Worst. I will give mine two or three seasons and then fit a Blakes. Better start saving now.

 

[PetiteFleur]

You are correct, the average chandler has no idea that Tonval is only a brass; I suspect they will last a year or so but for peace of mind change them to bronze. Bronze ones are roughly three times the price of 'cheap' Tonval ones; ie about £20 for bronze 1½" hull fitting. ASAP supplies have bronze ones(as well as Tonval).

 

[Alcyone]

I'm shocked by reading that report. We bought some ECS ones. The ECS website lists several items as being DZR (dezincification resistant) brass, but not the through hull fittings. I'm concerned now, and will be seeking clarification before I fit the ones I've bought.

Isn't there a case for these items being not fit for purpose?