Should you replace both radiators.

[dbeesley1]

Hi, my 98 boxster overheats. The supply line to the radiators gets hot but the return line doesn't. After 20 minutes, coolant starts to overflow out of the trunk.

Does anyone know what part of the radiator setup could be responsible for the failure? I think I am going to order both left and right radiators to progress this but thought it would be worth a post to share my experience and ask what others had done regarding diagnosing and repairing a faulty radiator.

So far, the story goes as follows:
- idler pulley next to alternator fails
- car overheats and I get it home on the flatbed
- trunk full of water so I replaced coolant tank
- I guessed that the water pump/thermostat might be responsible for the cooling failure..replaced both and no change.. Car still overheats after 20 mins.

I used the airlift to add the distilled water. I also ran water from the garden hose, through a kitchen plumbing setup to try and flush the radiator. I put the water into the 2 rubber hoses where you would normally drain the coolant. The water flushed through but I guess there is still a rad problem because the return line remained cool.

Any advice appreciated.

Thanks
Dave B