Mixed Metals Mess

ducked

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Here on a T piece which I THINK is intended to be used to flush the salteater cooling circuit by closing the seacock, and sticking the hose in a bucket of fresh water. Seems to be s mix of stainless steel pipe, steel compression fittings (quite rusty) and brass (domestic?) fittings, such as the valve. I suppose it would be worse if it all took salt water.

Ill clean it up somr.

Is there any suitable lube for the brass ball valve?
 
No, lever moves ok.

I buzzed the rust off with a coke can disk, separated most of the components, put PTFE tape on the threads, put it back together, and abraded it some more using boiled linseed oill as a binder. Given the mixture of metals I would have expected it to be worse, but I did run antifreeze in last year.

I expect I’ll have to teplace it with something more corrosion resistant once its exposed to salt

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Is it worth getting all exited about something which is probably used once a year to flush the engine and exhaust with freshwater/antifreeze. I have something similar, which has been in use for 20 years without any problems. Different if it's a part of a permanent installation on the boat.
 
Is it worth getting all exited about something which is probably used once a year to flush the engine and exhaust with freshwater/antifreeze. I have something similar, which has been in use for 20 years without any problems. Different if it's a part of a permanent installation on the boat.
Well, the "top" of the T is the cooling water intake path, so it kind of IS a part of a permanent installation on the boat.

Theres a similar ball valve on the water intake through hull, which had not quite such mixed metals, though showing pink-under-crustiness that I took to be the dreaded dezincing of its bronze bits.

I similarly stripped it and worked some grease into the ball valve, which seems to operate smoothly. Actual through hull fitting seems to be glassed-in. Cant see how the external strainer is supposed to come off either.

The through hull has a wide hex nut holding it in the hull, which is either very shallow, and so hard to grip with a spanner OR its glassed in, which would be worse. The external strainer may be integral with the through hull since I cant see any fastners on it. This is the ONLY filtration on the.intake path, a deficiency I will have to address.

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I would reiterate vyv's post 5. This has happened to me
Yes, I did that when I stripped both assemblies, taking the pivot apart. You dont seem to be able to remove the actual ball valves but I worked them in grease.

The flushing T-piece ball valve (which should only have seen fresh water/antifreeze) remains stiffer than the seacock one but the latter is slightly different and may be better quality. Had B-100 written on the handle.

The handles in both appear to be mild steel and fairly flimsy, and I would expect them to have short and unpleasant lives in a marine environment.
 
Any recommendations for intake filtration?

Perhaps something like this?

Seaflo Sea Water Filter 13 mm / 16 mm / 19 mm - Dale Sailing

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Any recommendations for intake filtration?

Perhaps something like this?

Seaflo Sea Water Filter 13 mm / 16 mm / 19 mm - Dale Sailing

SF-SWF002_1-510x510.jpg
I replaced the old bronze one incorporated into the seacock with a similar one, Vetus in my case. A very worthwhile change. The huge increase in strainer surface area meant less likelihood of clogging, which happened to us many times transiting the Canal du Midi. Far easier to clean out standing up.
 
Pretty universal now on new installations. Useful if you can mount it immediately above the intake to give you the option of rodding if the intake gets blocked. You can do away with your valve arrangement as you can run freshwater through the strainer if you mount it above the waterline.

Personally I would get rid of that external strainer and just use a plain 1/2" through hull and ball valve all in DZR. Might give the opportunity to relocate the intake in a better place. I did this on my GH where the original intake was difficult to access under the cockpit floor. Took the whole fitting out and glassed up the hole. New intake easily accessible in the engine bay with strainer above.
 
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Needs something, since the narrow bore outlet from the thermostat housing, which I think supplies the exhaust, was blocked airtight with what looked like grass (Seagrass?).

I would have expected the exhaust to be melted, but I did attempt a quick half-assed gravity flush with antifreeze before my return to Taiwan last year, so I suppose that could have blocked it.
 
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