Coolant disappearing

[Topman121]

Hi all My new to me 2016 superb L&K coolant level was dropping to below min level every 3 or so days, I topped it up from below min to max every time. Car has 120k miles with full Skoda dealer history to 118k last serviced at dealer in January. I’ve changed the T belt kit and waterpump 3 days ago with genuine parts for peace of mind and noticed the waterpump impeller shield has seized in the closed position, thinking this was my problem sorted with the new pump but after bleeding the car properly I’m sure there’s no more air in the system the coolant level is still dropping!? New EGR cooler was fitted at dealer last year, no visible leaks anywhere. New coolant tank and cap fitted also 3 days ago? Anyone shed any light on this? Cars not over heating, no pressure in coolant tank next morning and not mixing oil or water. Thanks

[Paw5]

I have exactly the same problem! Got me stumped 🤔 

[NJRJ]

If push comes to shove you could try something like a drain tracing dye and a UV light (https://www.toolstation.com/drain-tracing-dye/p19855?searchstr=drain dye) (or something similar). You'd need to check it isn't harmful to any parts of the system - with a big leak the system will be clear water (or flush it in case it reacts) and leave it a day or two then examine circuit with UV, any drips/steam stains should show, then fix it, flush well and get anti freeze/system inhibitor back in there sharpish.

[Topman121]

Since my last post my car has lost zero coolant in 1500 miles now today I’ve noticed it’s gone from max to min level in a few days (checked level last on Thursday) gona leave it to see if it goes below min level and triggers the coolant light maybe car is just working out air bubbles after replacing T belt kit and pump?

[Sheriff]

Did you ever get to the bottom of this?

 

Mine was 4 years old on Saturday and as a present to me, it gave me the low coolant light on Saturday night. I checked and couldn't see any leaks and temp was steady at 90 degrees with no pressure in expansion tank and no sign of any oil in the water. Tried topping it a couple of times but light came back on after 6 or 7 miles. Booked it in to garage for investigation and water pump bearings had gone. They said they growled when spun. New water pump and cambelt, a year early but it's done 112k. So far so good with new parts  

[drewellis]

This was happening to me. It’s a common fault, the Superb has a coolant pump which has a plastic housing and often fails or cracks. I think there is a revised part which isn’t covered by any recalls as it wasn’t “common enough”

 

{{ EDIT: Maybe my engine differs to yours

(2.0 220bhp) but I asked him to do the cambelt but he said that this plastic water/coolant pump was not run by the cambelt so that would be an unnecessary cost - a bit like changing your head gasket with your spark plugs 🤷‍♂️ }}
 

I ended up paying about £450 to replace it, and that was an independent VAG specialist, can’t imagine Skoda prices!

 

Initially I took the car for diagnosis and they took the diagnosis cost off the bill at the end.

They said it only leaks when engine is running and hot, and because of the location of the pump plus the plastic under trays meant that no puddle would form on the driveway.

 

I hope this isn’t your issue as it’s an expensive one, but it’s worth paying for a diagnosis to avoid irreversible damage to your engine.

 

Mine has been fixed for a couple of months now and coolant hasn’t moved 👍

Edited 7 July, 2020 by drewellis