Hi guys, 

 

Apologies if this has been covered and please direct me to the relevant post if it has (I did have a search but couldn't find a match). My Octavia vrs mk3 has just been in for a water pump change due to the common issue which we all know of. Everything seems fine now (no overheating) but there is an issue with my coolant level. I went to the car this morning and it had dropped overnight to well below minimum. I then topped it up to between the min and max lines and drove it to work as normal. When checking the level at work it had gone above the max line suggesting that I have no leaks but for some reason its not coming back into the expansion tank properly, Its been pressure tested and there are no visible leaks so could this just be an airlock or something else? Is there a known problem when the coolant would be sucked out of the expansion tank upon cooling as extreme as this? 

 

Look forward to your opinions. I will obviously re contact the garage as it is related to the work carried out but wanted to have some knowledge from those more in the know, before I take it back. 

 

Cheers, 

 

cm90

Airlock for sure, cycle the heater a few times between hot and cold.

So after you've driven it to work, it's above maximum - what makes you think it's not going back into the expansion tank properly?

 

Gaz

1 hour ago, CallmeGaz said:

So after you've driven it to work, it's above maximum - what makes you think it's not going back into the expansion tank properly?

 

Gaz

 

@CallmeGaz sorry I'm not all that knowledgable with cars but my understanding is that the coolant should fluctuate between the minimum and maximum lines generally as it expands when hot and then cools. I'm guessing that if I ignore the coolant light on the dashboard and drove it it would probably sort itself out but why would the coolant be dropping so far below the minimum prompting a warning light? Thats what I mean by not going into the expansion tank properly, because if no coolant is being lost, surely it should stay above minimum in the expansion tank?

 

Sorry for the long reply! 

I would be taking the problem up with the company who replaced the water pump. These engines have a myriad of pipe work and circuits and if not correctly filled can cause problems with air locks. Gone are the days when you squeezed the top and bottom rad hoses and turned the heater to hot.