2004 Avensis 2.4 T-Spiirit (Automatic Transmission) 2AZ-FSE engine 2362 cc - leaking radiator, will "K-Seal" help?

[A583_Blackpool]

As described, the issue is a leaking radiator, this was diagnosed by a local recovery mechanic who noticed a red line due to antifreeze leaking out. 

The car is now 17 years old and I am trying to avoid unnecessary expense. I remember that many years ago my father used "Radweld" on a couple of old Fords and Vauxhalls he owned . The local accessory shop do not stock "Radweld" but sold me a bottle of "K-Seal" which they said is a similar product. The reviews of these products are not all positive so has anyone tried K-Seal and how well does it work? I understand this Avensis model is quite rare so would a new radiator be hard to source?

Thank You

[ToyotaGang]

How to Use K-Seal ®

Shake the bottle vigorously and add the entire contents to the radiator or header/expansion tank. If adding to the radiator do not pour directly onto the radiator core. ...

Run the engine up to operating temperature. ...

Either replace the cooling system contents or leave K-Seal in the system.

 

I would personally not use this. I would rather just replace the radiater and not worried about it anymore. The 2AZ is used on a lot of other Toyota cars, so parts are out there.

Hope you find a solution!

[yossarian247]

I have tried K Seal in a few older cars and in my experience it either a) doesn't work at all or b) slows the leak down for a few months, then it returns as bad as ever.

I once used it in a diesel Citroen and it made no difference to the coolant loss so I admitted defeat and ordered a new radiator. As I was lifting the old radiator out of the car the entire bottom of the rad fell off and landed with a heap of sludge and rust on my feet! The old radiator hadn't actually looked in that bad condition while it was still in the car but clearly the bottom had been rusting out of it for a while. Lucky it hadn't decided to fall apart on the motorway.

[ToyotaGang]

Agree. But impressive the old radioter held up 17 years!

[alan333]

On 6/19/2021 at 4:30 PM, A583_Blackpool said:

As described, the issue is a leaking radiator, this was diagnosed by a local recovery mechanic who noticed a red line due to antifreeze leaking out. 

The car is now 17 years old and I am trying to avoid unnecessary expense. I remember that many years ago my father used "Radweld" on a couple of old Fords and Vauxhalls he owned . The local accessory shop do not stock "Radweld" but sold me a bottle of "K-Seal" which they said is a similar product. The reviews of these products are not all positive so has anyone tried K-Seal and how well does it work? I understand this Avensis model is quite rare so would a new radiator be hard to source?

Thank You

I wouldn't use any sealer in the coolant system, it works by clogging up the hole causing the leak (if it works at all), but also clogs up the important small waterways the system uses to cool itself.

Radiators are basically made from the top and bottom parts (specific to your particular car), plus the core (generic but must be the correct size).  Try phoning your local radiator specialists, who can re-use your old top and bottom parts, and fit them to a new core, usually cheaper than buying a new radiator.