3 replies to this topic

[Haynes]

Ok, its probably the head gasket but seeking a sanity check.

 

Engine is a 998 A+, Stage 1.  Water is coming out of the overflow, i've put the overflow tube into a bottle, as a catch tank to confirm this.

 

Compression test is all good, consistent across all 4 cylinders,  There's no visible smoke at all from the exhaust and the oil is clear.

 

Running from cold with the cap off, there's no bubbles.  When its up to temperature, with cap off, there are some small bubbles but cant tell if that's just due to the near boiling of the water?

 

Temperature gauge doesnt show any signs of overheating - what does that indicate?  Ie does that suggest its not an overheating problem, more likely over pressurising??

 

Top hose and heater hoses all get warm.

 

I have tried a new 15lb radiator cap which hasn't helped.  There is pressure on the spring and rad neck doesn't appear to be damaged.

 

Fan looks ok, with smooth side facing the engine.  However the fan doesn't fully sit within the shroud, the rads probably a bit too far away due to a fabricated top bracket.

 

Is it time to take the head off or is there anything else to look at first?

 

[cal844]

I'd sniff test the coolant for exhaust gases before removing the head

[Spider]

You maybe loosing coolant of you're over filling the cooling system, the coolant should be filled to about 20 mm down from the lower part of the filler next of you don't have a header / expansion tank.

The small bubbles you are seeing can be from the seal starting to go in the water pump.

[68+86auto]

Never assume a head gasket without testing it. People have a tendency to guess the worst instead of properly diagnosing the issue.

 

 

I'd sniff test the coolant for exhaust gases before removing the head

 

That's how I do it, small leaks seem to show up better that way than via pressure testing. Alternatively I use a pressure tester and run the engine. If neither of those options are available, use a rubber glove over the radiator neck and seal the overflow pipe. run the engine, rev it and see if the glove inflates.

Edited by 68+86auto, Today, 12:10 AM.