White gunk near valve cover

[jeremyg]

Can anyone identify this white crust? I replaced the valve cover gasket a couple weeks ago and cleaned it all so it’s fairly recent. Looks like it could be coolant? Some initial reading was suggesting a head gasket, but I was thinking that it could also be the gasket from where the thermostat is (I think) in front of the engine.

Shot from the front of the engine looking at the left side of the valve cover.

 

[mattressking]

Dried coolant from coolant sensor or coolant pipe off head

 

[toy_tek]

That looks like calcium deposits. Are you by chance using tap water mixed with antifreeze?

 

[Spook50]

That looks like calcium deposits. Are you by chance using tap water mixed with antifreeze?

My thoughts too. Boy I hope that ain't the case

 

[OSS]

My guess: the freeze plug on top of the head is weeping. (mine did). That white crusty stuff is dried up funky coolant/water mix

 

[jeremyg]

No, used 50/50. Trying to remember if I had to top off with hose water in a pinch after I started leaking. It’s pretty easy to get the stuff off so I think it’s just dried coolant and not calcium deposit, which I imagine would have to be scraped off.

Going to try replacing the gasket around the coolant sensor/thermostat

 

[Skreddy]

If it’s not around the thermostat gasket, it’s probably not the cause. I agree it looks like a weeping freeze plug (the one all the stuff is around). Or from, as said, the fittings coming out farther back on the head for coolant pipe or temp sensor.

It cleans easily, is it gooey or powdery or hard? If it’s gooey, look under oil fill cap and see if you have the same there.

Wipe it off and watch it run, should be relatively easy to see where it’s coming from.