Think this is freeze damage?

[Clucas]

So this was completely unexpected... Winterized last fall as I have done each year since 2007 without incident. Started her up yesterday and had water spraying all over the cabin due to a split in the check valve in the bypass between the water jacket T fitting and the thermostat housing (Moyer part CSOT_01_515). There are two splits in the body of the check valve around a part of the fitting that looks pretty beefy and futhermore points downward -- not sure how any water could have been trapped there. It looks like freeze damage, but I'm not convinced. Anyone have any thoughts? No evidence of freeze damage anywhere else.

I don't run with a thermostat and control temp using the a small ball valve and check valve in the bypass loop.

Chris

[Mo]

Most time you see a valve or portion of one broken by frost it is usually a longitudinal break and not circumferential. I suppose it could be a frost break but not entirely convinced either.

[hanleyclifford]

The check valve did it's job and did not allow water to leak down thru it.

[sailingchance]

Materials

IS that brass or bronze? It looks like a faulty casting. It could be freezing, but ALOT of water would have had to be trapped right there. it would have taken freezing plus pressure.

[JOHN COOKSON]

+1 on the faulty casting.
If you bought it from Moyer see if they will accept a return for inspection and possible replacement.

TRUE GRIT

[Mo]

I've seen valves (huge valves) break under a shock load and higher pressure water comes and hits the closed valve...have even seen where it blows a pipe open. That was the fire system on an oil rig...can't see that happening in this case but does look similar???

[Clucas]

IS that brass or bronze? It looks like a faulty casting. It could be freezing, but ALOT of water would have had to be trapped right there. it would have taken freezing plus pressure.

It's brass. The crack indicated at the lower arrow runs almost the entire circumference of the valve. The cracks (both) lie below where the check valve 'plunger' is -- there was no water (or antifreeze, for that matter) trapped there. I'll return it to Moyer to get it inspected, but already ordered a replacement. I put a coupling in its place in the interim -- engine purring very nicely (no freeze damage) -- marking an end to my winter A4 project of removing the water jacket cover and cleaning her out. Here's the before and after...