Radiator Repair & Replacement
The radiator is the part that throws engine heat into the air, and when its core leaks or clogs the whole cooling system loses capacity. This page is about the radiator itself: finding out whether it can be repaired or must be replaced, fitting it correctly and refilling the system with the right coolant.
From AED 599Written quote after diagnosis, before work startsConvenience fee applicable · shown on your written quote
- 3-5 hours for most cars; longer if the front end must be dismantled
- Pickup and delivery from your door
- Convenience fee applicable · shown on your written quote
- Diagnosis free with repair
Signs you need radiator repair & replacement
- Green, pink or orange fluid dripping under the front of the car after it has been parked
- The coolant reservoir needs topping up every week or two with no visible puddle
- Wet, crusty white or coloured deposits on the radiator end tanks or seams
- Temperature needle climbing in slow traffic but settling once you are moving
- The upper radiator hose feels hot while the lower one stays cool
- Rusty, sludgy or oily coolant when you look into the reservoir
What usually causes it
Cracked plastic end tanks
Most modern radiators have plastic tanks crimped onto an aluminium core. After years of heating and cooling the plastic turns brittle and the seam or the tank wall starts to weep, usually first near the hose necks.
Corrosion from tired coolant
Coolant carries inhibitors that wear out. Once they are gone the metal inside the core corrodes from within, and tiny pinholes appear that only leak when the system is hot and under pressure.
Internal blockage
Scale, rust flakes and old stop-leak additives can narrow the thin core tubes. Fewer open tubes means less heat leaves the engine, and the car overheats when the load is high even though the level looks fine.
External damage and clogged fins
Stones thrown up on the highway bend the fins or puncture the core. Sand and leaf debris packed between the radiator and the air-conditioning condenser also cut airflow and heat the whole stack.
How we do radiator repair & replacement
- 1
Cold pressure test
With the engine fully cool, we pressurise the system with a hand pump and watch the gauge. A falling reading and a wet spot show the exact leak, and we test the pressure cap on the same tool.
- 2
Repair or replace decision
A damaged copper or aluminium core can sometimes be repaired, but a radiator with plastic tanks and a leaking seam is normally replaced. You see the reason on the quote, with the part choice of OEM, aftermarket or used.
- 3
Drain, remove and fit
Coolant is drained into a container, then the fan shroud, hoses and any transmission cooler lines are disconnected. The new radiator goes in with fresh seals, and the lines and clips are refitted.
- 4
Refill, bleed and heat test
The system is filled with the coolant type your manufacturer specifies and bled of trapped air. We run the engine to temperature, check the fans cut in, and recheck for leaks and the level once it has cooled.
By make and model
Nissan
Some older Nissan automatics have the transmission fluid cooler built into the radiator. If the cooler wall fails, coolant and gearbox oil can mix, so we check the transmission fluid whenever one of these radiators is replaced.
In Dubai, Sharjah and Ajman
Summer in the Gulf means very high underbonnet temperatures and long periods of idling, so a radiator that is only slightly down on capacity shows itself quickly here. Sand also collects between the condenser and radiator at the front of the car, which is why we blow the stack clean from the engine side during every replacement.
Questions about radiator repair & replacement
Can a leaking radiator be fixed with a bottle of sealant?
We do not recommend it. Sealant can plug the leak for a short while, but it also lodges in narrow core tubes and the heater matrix, and the radiator still needs replacing later, often with a bigger bill.
How do I know it is the radiator and not the water pump or hoses?
We pressure test the whole system and see where the pressure drops. Hoses, the pump seal, the radiator and the heater all leak in different places, so the test separates them.
Do I have to change the coolant too?
Yes. The system is drained to remove the radiator, and the old coolant has usually lost its protection. Fresh coolant of the correct specification goes in, because mixing types can cause sludge.
Is it safe to drive to the workshop with a slow leak?
Only for a short distance with the level checked beforehand and the temperature gauge watched. If it climbs, stop. Our pickup and delivery option avoids the risk.
My car overheats but the radiator is not leaking. Is that still this job?
Possibly, if the core is blocked inside. A flow and temperature check tells us. If the cause is a fan or thermostat instead, our overheating page covers that diagnosis.
Last updated
Get a written quote
Tell us about your car. You get an itemised quote before any work starts, and you choose OEM, aftermarket or used parts.