S40 V40 Cars: Unexplained coolant problem

[VolvoDID]

Hi new member,
I have a 2014 v40 d3 with 59,500 miles on the clock . There is an ongoing issue with a coolant leak, after 5 visits to 2 separate garages, no closer to finding cause.
I get a message ‘heavy load, shift down’ after 30 miles of driving, then a warning that engine temp is high and to reduce speed, then ‘engine temp high stop safely’, then ‘coolant level low’ message. Once I stop, engine gets even hotter. Coolant level goes from max to below min after every journey of 30 miles. No evidence of a leak on ground or in engine area. Cap on reservoir has been replaced twice & cam belt & water pump replaced about a month ago (incidentally, these issues started shortly after this) Garages have bled the system & done a pressure test plus other checks, unsure exactly what (sorry for lack of tech info,complete car maintenace novice). Got car back again from garage on Friday with second new reservoir cap (official Volvo one as previous was generic) got 35miles & only message I got was ‘coolant level low stop safely’ which briefly flashed up & that was it. Once home, engine was cool but checked after an hour & it was hot & the coolant was below min. Have checked this morning and it is still at the same level. No other symptoms, head gasket testing points to no issues there. Anyone experienced this or have any suggestions please? I have several long distance journeys coming up and currently will not be able to rely on my car for these. Thank you.

[Kev0607]

Is it an aftermarket water pump by any chance that the garage fitted? I've heard these can cause issues.

Fit a genuine pump.

[GrahamBrown1]

Very recent case of this from another forum member after having a timing belt and water pump change.

If the water pump has failed or is of poor quality it won’t circulate coolant correctly.

Genuine Volvo pumps very rarely require changing and is not a standard practise when the timing belts are changed. It is generally the norm on other makes but not Volvo.

I would get the pump replaced for genuine if of course your replacements were not genuine Volvo parts.

[VolvoDID]

Thank you very much to both of you. I recently had to call out the AA because of this issue and got towed home (from near Portsmouth to Cambs) and the patrolman also thought that the water pump was the likely cause. I mentioned this to both garages and they were a bit vague with their responses so I will now go back and ask if it was a Volvo water pump that was fitted. I really appreciate your help, it gives me hope that this can be resolved!

[NI_Volvo_Nut]

While I would concur with the above, I did have a D2 which was doing similar thing and it was a head gasket / cracked liner issue, coolant system pressurising and actually forced the coolant out of the expansion tank, bringing on the low coolant warning.