[wanderer147]

Recently had the timing belt and water pump replaced by my usual local garage. Since then have noticed that the coolant level in the expansion tank keeps dropping. Can't see any obvious leaks or water residue anywhere as the result of a leak either. Is it possible the new water pump was faulty or a different failure. Car drives as normal, reaches 90 degree temp ok and stays there during driving. Having to put about 0.5litres in every 100 miles or so. Any ideas folks?

 

[raingod]

My previous 156 had a leak on the coolant reservoir where the coolant pipe fits onto the fitting that lets the coolant come back into it. Only noticed it when the engine (and coolant) was up to temperature and with the engine running, looking at the reservoir, moved the pipe from the engine to see the leak. My 'invisible' coolant leak was due to the coolant coming out onto a hot reservoir and evaporating before the leak was spotted before 'forcing it' to leak in a bigger way to actually see it.
Solution was simply to swap the reservoir and all was well.

 

[dgmayhead]

Hopefully this is a faulty cap that allows evaporation from the header tank. Get the car running at temperature and see if the cap is hissing.
Worse case is head gasket leak. Do a sniff test on the reservoir. Kits are quite cheap and easy to use.

 

[halftone]

I'm sure I read somewhere that the 1.6 waterpump is inclined to leak past the gasket unless installed with silicone sealant, so if you can't find a leak it may be worth taking the belt cover off to have a look.

 

[wanderer147]

Had the car up to temp on the drive today, had a good look as its running and can't see any drips. Check caps for mayo and oil cap is clean. Can't here anything hissing around the cap, is there a way to to test without just buying a new one? There does seem as if there is air bubbles or condensation on the inside of the expansion tank tho, as if air in the system.

 

[kandlbarrett]

It might be air in the system taking time to bleed out. Or it is possible to damage the "O" ring that seals the water pump; I always use a little silicon grease to help ease it in. Because it is behind plastic covers it is possible that a small leak here would evaporate before it dripped out to the bottom of the covers so you wouldn't know that it was leaking.

 

[wanderer147]

Ok guys, marked the coolant level on the tank and went out to get the car up to temp, came back and the level was a bit higher than when I left. Took the cap of and bleed the radiator using the bleed screw - few air bubbles but otherwise a steady flow of hot coolant. Heaters in car were blowing hot and cold nicely. Refit tank lid and the level is still higher than when i left. Took a photo of the tank now, are the droplets on the tank roof normal?

 

[Seedsy]

Any update?

Hi, my 147 has been having the same problem for the past couple of months. Did you find what the problem was?
I've tried even the likes of K-seal but still no joy.