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Kia Sorento - Kia Sorrento loosing coolant - Thomas270

Hi,

My kia sorrento was losing coolant, main dealer diagnosed that the radiator was corroded and I replaced it. Got it back and noticed coolant reservoir was dropping. Noticed coolant around radiator cap then saw that the overflow tube from the radiator cap had snapped and tube leading back to reservoir dangling. I assume garage had damaged it when replacing radiator and took it back. Dealer repaired the overflow pipe but said they didn't damage it and they believe head gasket is leaking pressure into cooling system and it has blown it off. I hadn't noticed any signs of head gasket failure other than coolant Leak, no overheating, no smoke/smell, no loss of power, no milkshake oil and no bubbling from radiator cap. Mechanic is saying he pressure tested it over night and is lost pressure and when running cap is rated to 1.1 bar and system is running at 1.3 bar so system is over pressured due to head gasket leaking. I took my own combustion leak test to garage to test and left it in radiator cap for 45 mins and liquid stay blue whole time.

Is the mechanic having me on?

Edited by Thomas Strong on 24/06/2023 at 13:33

Kia Sorento - Kia Sorrento loosing coolant - elekie&a/c doctor
Any evidence of coolant in the oil ? How does your mechanic know it’s running 1.3 bar pressure?
Kia Sorento - Kia Sorrento loosing coolant - Thomas270
Any evidence of coolant in the oil ? How does your mechanic know it’s running 1.3 bar pressure?


No oil is perfectly fine, said he connected pressure gauge to radiator cap and left car running.

Kia Sorento - Kia Sorrento loosing coolant - elekie&a/c doctor
Your mechanic would need a very accurate gauge to measure a difference of 3 psi in coolant pressure. Is it still losing water ?
Kia Sorento - Kia Sorrento loosing coolant - Thomas270

Not had it back since they repaired the overflow pipe, planning to refuse the head gasket repair and wait and see if coolant keeps going down

Kia Sorento - Kia Sorrento loosing coolant - Andrew-T

Maybe an airlock is gradually dissipating following the rad replacement ?

Kia Sorento - Kia Sorrento loosing coolant - edlithgow

Maybe an airlock is gradually dissipating following the rad replacement ?

Quite likely. I now allow the coolant to boil (disabling fan) into an expansion funnel jammed in rad when the system has been drained, otherwise it takes a long time for airlocks to clear.