Strange white 'fuzz' on oil cooler fitting

[thematt]

Hey all, first post here. I'm super new and learning as quick as I can with my new to me Tartan 42. Recently I've noticed a strange white fuzz on our oil cooler fitting (westerbeke w50). It's almost salt-like, though I haven't completely ruled it out the location doesn't make sense for it to be salt water. The fuzz grows in the same location every time, even after tightening hose clamps and not using the engine. I was worried about a stray current, but the anode seems fine, and I'm not seeing any voltage on my multimeter. I haven't tested for AC yet, but will tonight. In the attached photos you can see the fuzz on the fitting which is the raw water loop. The clean fittings are the oil loops and the plug is the anode. I cleaned the fitting off and applied some corrosion block, but the fuzz still forms.


Thanks for any help and your time reading this!

[a64pilot]

Yeah that’s salt, I’d bet money. See it on the drain fitting right beside that fitting?
I have never seen a fitting go bad like that, but I bet you have one that has, ideally replace with a bronze one, but that may be like saying replace with a gold one, I don’t know where you would find bronze small fittings like that, perhaps someone else does? Pretty sure it’s brass and brass doesn’t last in salt water.

I believe that fitting itself is actually leaking, one way to know for sure is clean it well and dry it thoroughly, then put baby powder on it and run it, if there is any liquid at all the baby powder will show it.

Of course I’m betting water flows through that fitting and not oil, cause if oil does, well then I’m stumped

[stormalong]

Is there salt water running through those hoses? I think what you are seeing is zinc from the brass fittings de-zincifing - the brass gets porous as the zinc is elecrolytically removed from the brass. It would be a good idea to replace those fittings - with bronze ones if you can find them. If you can't find bronze or red brass plan on replacing them periodically.

[Wotname]

What the others said +1.

I'm thinking you have a brass fitting in the raw water loop and the brass has dezincified (sp?) and is becoming porous. The white stuff is probably not NaCl salt, rather other salts deposited by the action of warm/hot sea water and the brass (calcium / magnesium / etc).

I agree that bronze would be way better and last a lifetime but brass needs to be replaced often. Maybe every couple of years????????

[thematt]

You guys are awesome! That makes perfect sense. Got home and took some fine sandpaper and 'polished' up the surface where the fuzz grows. Sure enough micro pitting and in the spot where the fuzz grows is a little copper colored spot. I don't have baby powder on hand, but I wrapped some absorbent cloth and will see what happens.



No AC detected either, so do you think this just a result of the salt water in the hose causing electrolysis over time?


I'll see if I can get a fitting ordered. Thanks all!

[Wotname]

Originally Posted by thematt

..........



No AC detected either, so do you think this just a result of the salt water in the hose causing electrolysis over time?


I'll see if I can get a fitting ordered. Thanks all!

More because it is brass, not bronze.

Brass and sea water don't play well together where as sea water and bronze live a long and happy existence together.

[rbk]

Originally Posted by thematt

You guys are awesome! That makes perfect sense. Got home and took some fine sandpaper and 'polished' up the surface where the fuzz grows. Sure enough micro pitting and in the spot where the fuzz grows is a little copper colored spot. I don't have baby powder on hand, but I wrapped some absorbent cloth and will see what happens.



No AC detected either, so do you think this just a result of the salt water in the hose causing electrolysis over time?


I'll see if I can get a fitting ordered. Thanks all!

No electrolysis, galvanic corrosion. It is acting as a sacrificial anode (at least the zinc in the alloy is) while sitting in your steel engine. No different than you zinc in your prop shaft. I’m surprised it’s a raw water cooler engine, looks pretty new.

[Compass790]

You will be able to get an equivalent fitting/plug in 316 ss. Install with thread tape & or pipe sealant goop

[thematt]

It's a Westerebeke W50, manufactured in 1980. The original schematics are still availble online. The engine itself has a fresh water coolant loop via the HX, but the oil is cooled with this small oil cooler (pictured). I beleive it's copper or perhaps bronze. Where paint has flecked away it's a nice rose copper color, but that's only a guess. The previous owner had it replaced relatively recently.



Given the fitting is not installed in Steel would the SS still be a good option?

[skipperpete]

Replace the cooler anode[emoji780][emoji780]

[rbk]

Originally Posted by thematt

It's a Westerebeke W50, manufactured in 1980. The original schematics are still availble online. The engine itself has a fresh water coolant loop via the HX, but the oil is cooled with this small oil cooler (pictured). I beleive it's copper or perhaps bronze. Where paint has flecked away it's a nice rose copper color, but that's only a guess. The previous owner had it replaced relatively recently.



Given the fitting is not installed in Steel would the SS still be a good option?

Yes but use an isolator like Lanocote or Tef gel so they don’t get welded together in the future.

[thematt]

Originally Posted by skipperpete

Replace the cooler anode[emoji780][emoji780]

It's super fresh still ~90%. I'll clean the threads out and make sure contact is good this weekend. I would hate to think the cooler is being eaten 😬

[GordMay]

Greetings and welcome aboard the CF, Matt.

[transmitterdan]

Originally Posted by thematt

It's super fresh still ~90%. I'll clean the threads out and make sure contact is good this weekend. I would hate to think the cooler is being eaten [emoji51]

That plug looks similar to a sacrificial anode. When you remove it (after closing the sea cock) take a picture and post. I’m guessing that is not just a plug. What does the parts manual say it is?

[thematt]

Originally Posted by transmitterdan

That plug looks similar to a sacrificial anode. When you remove it (after closing the sea cock) take a picture and post. I’m guessing that is not just a plug. What does the parts manual say it is?

It's the anode. You can see in my initial post I said the plug is the anode, I was attempting to describe the oil cooler features and seems I've added some confusion. In my previous posts I've noted the anode is in good shape. At about 90%. I'm concerned there isn't good contact though.


Thanks again everyone for warm welcome and help! I'll dig into this tonight or tomorrow.