What could this be????

[TFU] Thegoon84

[TFU] Thegoon84

[TFU] Thegoon84

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What could this be?

Our Car has very brown muddy water in the tank, I thought the head gasket was going. So took her into the garage for a pressure test and it came back as fine. However when the car is left running for a while it will dump quite a bit of water at 100’c, the cooling fan also kicks in. The garage took the car for a drive yesterday and said its running very well :confused:.

Does anybody know what this might be? The mechanic told me he’s going to completely drain the water system today to flush out all the crap from the tank. Is there anything else it could be? Could an oil cooler cause mucky water and a water dump at 100’c?
 
Of course the fan will kick in if you just leave it there running? Not sure i am reading that bit right.

Probably only just needs to be flushed. Only way you are going to find out really.
 
Rybo89 said:
Of course the fan will kick in if you just leave it there running? Not sure i am reading that bit right.

Probably only just needs to be flushed. Only way you are going to find out really.
Click to expand...

Yeah due to it not having a temp gage on the dash they plugged it in and left the car running. Once it got to 100'c it just "dumps" quite a bit of water from somewhere.
 
My old civic was leaking water from the radiator when very hot. Also the water was beginning to darken (black when it finally exploded).

You checked all around the radiator? Might be tiniest hole somewhere on it that will leak once the pressure is up.

Mind you a able mechanic should be able to spot this.
 
How much water are we talking?

Could be a slight split in a coolant pipe that only leaks when there's a lot of pressure (from the hot water expanding)
 
could the Thermostat housing be leaking,? no water would pass by it until it opened when the engine gets hot. it would help to know the make and model of the car.
surly a garage would notice which part of the engine suddenly got wet when it does a ''dump''?
 
It's a pretty random question tbh - if the car is chucking out that much coolant it's just a case of getting the car on the lifts, raised enough to look underneath, standing back then watching where the water comes from when it chucks some out.

I would be willing to bet it's to do with the stat or housing though if it does it only when up to temp
 
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My MX5 has a pipe near the centre of the engine. It started leaking when up to a decent temp due to a very small hole in it. Time to start checking all the hoses!
 
Thanks for all the replies guys, I just wanted a few suggestion on what it could be. It sounds like its nothing too serious fingers crossed. Will update you later when I speak to the mechanic.
 
You still have not told us what car and which engine you have?

The cooling system is pressurised under normal operation, but there is a "safety" vent usually in the form of the radiator/expansion tank cap which is spring loaded. If the coolant boils for whatever reason, then the sudden pressure rise will cause coolant to be released, and there will normally be a small hose to direct this boiling hot coolant down toward the ground.

Brown murky coolant often comes from running neat water in an iron blocked engine. This causes internal corrosion that turns the water brown, and ultimately can cause blockage of internal cooling circuits including the radiator and the heater matrix, which obviously causes overheating.
 
We have just had the same issue diagnosed with our Saab and its terminal in our case - known issue with the engine.

initial diagnosis from a local indi garage were faulty expansion tank cap, termostat or possible waterpump (in that order).
 
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