Coolant loss

[wilsofar]

I know this has been covered before in various guises but I need to know if anyone has actually discovered the reason for coolant loss (between Max and Min) but no further.

Investigations at my local trusted garage have come to no conclusion but I noticed that a number of members have discovered coolant loss between the two marks but I have not seen any solution by them other than a small top up.

I have replaced the pressure cap twice (one of which purported to be OEM) and there is no trace of mayonnaise on the oil filler cap or any visible leakage anywhere so I’m stumped!

I know I can continue to keep topping up and as I don’t do many miles it would not be that frequent and not much anyway but I would like to find a solution as I would not want to sell the car knowing there was an underlying problem.

Please note that my garage recently topped up to Max and it stayed at that level for about a month then reduced to Min fairly quickly over a couple of weeks.

Any thoughts folks.

 

[Pedro]

Mine leaked showing different levels in the expansion bottle I could not find any leakage until one day I checked & it was hovering on the min so I got a camera & poked around the Thermoset tank & it was split on the seam/join leaking coolant down the gearbox so I replaced the Tank as have many other owners on here as it appears to be a generic fault & it has stopped losing coolant as far as the expansion cap goes I don't think you get discharge unless you can see the whiteish phosphate trail around the seal I still have the original cap & have no issues so don't regard everything your told about coolant loss it is a pressurised system not designed to lose any of the 6 .25 litres when its full to operating capacity & if your filling up make sure you mix it 50/50 in summer & if needed add some full strength during winter

 

[wilsofar]

Thanks Pedro.

Which tank is the one which had split -was it the expansion tank or something else out of sight?

 

[Pedro]

The tank I refer to is on the R/H/Side of the Engine opposite the battery it houses the thermostat & temp sensor (depending on the model) you will notice the radiator hose & engine coolant pipes connected to the black plastic unit with a bubble like shape unfortunately its a battery off job I'm afraid but many have done it as its a fairly easy fix if this it not the problem then you may have a issue elsewhere on the coolant side

 

[wilsofar]

Thanks for that.

 

[Buddy]

I have just finished changing the Thermostat housing and have only driven the car a few times, when hot the level drops to near min then returns when cold but there is a noise from the area of the pipes/stat housing for a few minutes after I switch off when hot, I have had other cars with turbos where they ran a cooling pump for the turbo for several minutes after shut down, does the RCZ? Or is it more likely to be a small leak under pressure? On the point about the 4pin connector giving two leads to two 2pin connectors, mine has the cable adaptor and it's indicating fine and the temp sits steady, warm up is quicker than with the original housing.