Composition of fittings on/in motor?

[Danny_Ocean]

I need to replace & add some fittings on my motor (e.g. - petcock drains for the exhaust manifolds). What type of material to use? Bronze, brass?<br /><br />Motor is raw-water (salt) cooled 454/330 Mercruiser I/O.<br /><br />Thanks in advance,<br /><br />D. Ocean<br />Pompano Beach, FLA

 

[Darian F.]

Re: Composition of fittings on/in motor?

most fittings on all Volvo Penta gas sterndrive<br />are brass. I never heard of bronze fittings, however I am not the boating authority on corrosion.

 

[navigator336]

Re: Composition of fittings on/in motor?

In general bronze is better to use as it is more noble (less likely to become an anode) than brass. However, I've never seen a bronze petcock. You can tell what you have now by observing the surface finish. If its smooth it's probably brass. If it is rough and looks like it was cast in sand, it's bronze.