Coolant leaking from valve cover?

I have a 2003 Toyota Camry with 210,000km on it. Today I popped the hood, noticed the coolant was slightly low in the over flow resavour so I looked around the engine bay. Now I know generally coolant does not go up that far and it’s just oil… But this has got my head turning. There’s a crusty coolant residue drip that looks to start at the valve cover. At first I thought maybe the water pump was leaking, and the pulley was spinning it farther up, or spraying back from a rad leak when driving. but the fact it’s crusty and A clear line that looks like a drip that’s a slow leak and has crusted over time makes me wonder. I mean generally coolant wouldn’t come out of the valve cover unless it was right full of coolant, causing enough pressure to push it out… Am I wrong ? Once I get to the shop on Monday I’m going to pressurize the cooling system and pull the spark plugs and the valve cover to look at the head, Any ideas? the highest spot I see the drip start is the valve cover, only thing I could think of is the intake leaking, and traveling over there but even then, it doesn’t make sense to me. Any ideas ? The thermostat housing is about 2.5" under so it can’t be that… It’s such a small leak, the resavoir is only down about maybe half an inch and the oil looks clean as can be… There’s some pictures below that you can somewhat see it.

Below the valve cover is the head.

And below the head is the head gasket between the head and engine block.

So, it might be an external head gasket leak.

Tester

It’s above the head gasket… Like a good length above it. Gravity would push the drip down, the coolant would not flow up wards if it was leaking.

Are you referring to the pink substance?

Tester

Yes… Not sure how well you can see it in the pictures. But you can only see part of the drip in the picture because the bracket that is bolted on to where the engine mount is covers the rest … It’s above the head gasket

Here’s what you do then.

Take brake parts cleaner and totally clean the area and let it dry.

Start the engine, and while the engine idles, take a flash light and look in the areas where you saw the witness stains. And I’m sure you’ll find the leak.

Teter

Before you pour oil in the radiator, The coolant is NOT oil. It’s mixture of ethylene or propylene glycol and water.

edit: op, you stated “Now I know generally coolant does not go up that far and it’s just oil.”

Gravity will cause coolant to flow downward when you aren’t moving, but the air currents under the hood, especially when the fan kicks in, can cause it to move upwards.

Hard to say from here, but my neighbor had a leak from the plumbing for the heated throttle body on his Ranger 4 banger. It was shooting coolant on to the bottom of the hood and top of the engine. Might be the same on this Camry.

I showed him how to cap it off since we don’t live in Siberia.

@BillRussell I know not to put oil in my radiator… Not sure why you thought that I was going to do that. @NYBo I hear what your saying and I was thinking the same thing… It’s just such a straight drip, that looks like it’s had coolant going down it slowly for awhile, if there was coolant in other places I’d completely agree, but all I can visually see is one straight line, and the highest point I see it coming from is the valve cover. Obviously I’m aware that it’s just oil up there, unless there’s a major issue with the head it self. If the fan was blowing it lets just say from a upper rad hose, would you not expect it to be in more then one spot? Kinda scarred dry coolant spots all over ?

@Murph64

The engine’s not operating hotter than normal, is it . . . ?

@db4690 No it isn’t… It’s stayed right in the middle of the temp gauge right at operating temp and I drove it all day. Rad is full of coolant, over flow is about half an inch down under full mark. And I know it’s dropped because I checked them All about 4500km ago and i can see visibly that it’s slowly leaking but the pink coolant crust that’s formed.

My guess, the suspected coolant leak – if that is what it is – isn’t from the valve cover. If the water pump is in that general vicinity, that’s be my first suspect. When the shaft seals starts to fail, its rotation can sling the coolant a fair bit. Usually there is a visible weep hole on water pumps, and if you can see any coolant inside that hole, the water pump is toast. If not that, remember the coolant is under pressure, like 7 pounds per square inch, so any small hose leak can create a squirting effect.