Author Topic: Coolant Loss from Expansion Tank  (Read 6203 times)

Offline kiakid2

  • Newbie
  • *
  • Posts: 40
  • I NEED TO UPDATE MY SIGNATURE!!!
  • Body: SUV
  • Colour: Soul Red Metallic
  • Engine: 2.2L 175ps
  • Fuel: Diesel
  • Model Grade: Sport Nav
  • Transmission: Manual
  • Year: 2017
Coolant Loss from Expansion Tank
« on: February 01, 2016, 08:58:59 am »
Bizarre or what – my coolant header tank that was full, lost water to 20mm below the low level mark. Booked the car in to be checked/pressure tested by the dealer and they confirmed that water was dripping from the A/C leak off and they suspected an internal fault with the heater matrix!

Obviously I am gutted as the car has already had a new gearbox fitted, now needs major surgery to replace the heater matrix that is buried under the dash………………….and at the weekend the windscreen received a direct hit causing a pound coin size chip damage in the drivers view angle, so it will fail the MOT when it is due.

To reduce down time I have said I will live with the leak it till the first service is due in April.

I have now driven over 500 miles including two long runs of 150 miles and the level has not dropped at all!
So where did the coolant go – could it have been an air lock, as I remember winding the heating up to 29 deg in December for the first time since buying the car at the end of August second hand with 3800 miles on the clock, that would have given full water flow through the heater matrix or could the pressure test have sealed a joint somewhere ……….only time will tell! 


Offline xtrailman

  • Sr. Member
  • ****
  • Posts: 535
  • From Worksop Great Britain.
  • Body: SUV
  • Colour: Sonic Silver Metallic
  • Engine: 2.2L 175ps
  • Fuel: Diesel
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2015
Re: Coolant Loss from Expansion Tank
« Reply #1 on: February 01, 2016, 12:58:32 pm »
It is strange.

To be honest i think you have done well to see the level, i find it difficult and have only checked it once.
It could be air as you say, but on the positive side you have now had 3 faults, so you should be good now.

Unless another 3 occur.  :)
Was 2013 Mazda CX-5 175 AWD sport nav Man 1663kg
Now 2015 Mazda CX-5 175 AWD sport nav Auto 1703 kg.
 Towing a 1565kg Bailey Valencia 2011 model.

Offline Deeps

  • Sr. Member
  • ****
  • Posts: 464
  • Located 20mins NW of Stuttgart, Germany
  • Body: SUV
  • Colour: Crystal White Pearlescent
  • Engine: 2.2L 150ps
  • Fuel: Diesel
  • Model Grade: SE-Lux
  • Transmission: Automatic
  • Year: 2015
Re: Coolant Loss from Expansion Tank
« Reply #2 on: February 02, 2016, 10:55:04 am »
Now you mention it, I recall reading something across on the German forum stating that some owners were experiencing trouble with the heating matrix with one symptom being that warm air was only being distributed to one side of the car and not equally between the two sides. Mazda are supposed to be aware of this problem with units being replaced FOC.
Mazda CX-5 Exclusive Line 2.2D (150PS) 6AT AWD tugging a 2016 Hymer Eriba Troll 542 Caravan (1300kg).

Offline xtrailman

  • Sr. Member
  • ****
  • Posts: 535
  • From Worksop Great Britain.
  • Body: SUV
  • Colour: Sonic Silver Metallic
  • Engine: 2.2L 175ps
  • Fuel: Diesel
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2015
Re: Coolant Loss from Expansion Tank
« Reply #3 on: February 02, 2016, 10:58:08 am »
I've read the same on 247, but it was thought to only affect very early cars.
Was 2013 Mazda CX-5 175 AWD sport nav Man 1663kg
Now 2015 Mazda CX-5 175 AWD sport nav Auto 1703 kg.
 Towing a 1565kg Bailey Valencia 2011 model.

Offline rmvf

  • Sr. Member
  • ****
  • Posts: 373
  • Body: SUV
  • Colour: Reflex Blue
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: Sport Nav
  • Transmission: Manual
  • Year: 2018
Re: Coolant Loss from Expansion Tank
« Reply #4 on: February 25, 2016, 06:52:05 pm »
I can verify that we had our heater matrix changed due to partial or total blockage, luckily it was under warranty,  I posted a thread last year which will still be there, cant remember last time I checked coolant level better do it tomorrow
Also running a pearl white petrol sport nav from 30/04/ 2012

Offline Willpower

  • East Anglia Mountain Rescue Team
  • Administrator
  • Sr. Member
  • ******
  • Posts: 442
  • Watching events
  • Body: SUV
  • Colour: Deep Crystal Blue
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: SE-L
  • Transmission: Manual
  • Year: 2015
Re: Coolant Loss from Expansion Tank
« Reply #5 on: February 25, 2016, 07:50:50 pm »
I can verify that we had our heater matrix changed due to partial or total blockage, luckily it was under warranty,  I posted a thread last year which will still be there,


http://mazdacx5forums.co.uk/index.php?topic=87.msg386#msg386

Offline rmvf

  • Sr. Member
  • ****
  • Posts: 373
  • Body: SUV
  • Colour: Reflex Blue
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: Sport Nav
  • Transmission: Manual
  • Year: 2018
Re: Coolant Loss from Expansion Tank
« Reply #6 on: February 26, 2016, 10:07:55 pm »
Thks Will
Also running a pearl white petrol sport nav from 30/04/ 2012

Mazda CX-5 Forums

Re: Coolant Loss from Expansion Tank
« Reply #6 on: February 26, 2016, 10:07:55 pm »