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We had an overheating problem on a Toyota Camry a couple of months ago, due to a faulty thermostat governing water flow.

The thermostat was replaced but at the weekend we have had another overheating problem, this time the head gasket has failed.

Should this problem have been picked up when we had the earlier problem and what is a reasonable quote for repair of a head gasket on a Camry?

Liam

From the "Ask Jack" archives - 14 December 2009

The fact the head gasket lasted a couple of months after the thermostat was replaced would suggest everything was OK at the time of the initial repair.

What has probably happened though is the gasket has suffered as a result of the thermostat failure and over the last few months it has progressively got weaker.

It would be interesting to know the distance the vehicle had travelled between failures.

Cooling system or overheating problems are something of a nightmare for repairers. Once a repair is carried out, standard practice is for a pressure test to be applied to the entire cooling system to check for any leaks as well as a road test to check for signs of overheating etc.

If everything checks out OK then there is little else that can be done.

Once the cooling system is up and running normally however, pressure is always going to be applied to the weakest point within the cooling system and there comes a point when a leak will develop. If the head gasket was in fact the weakest link then it was only a matter of time before it let go.

It is not uncommon for head gaskets to fail after an engine overheat, but the repairer would be at risk of carrying out unnecessary work if they removed the cylinder head when their initial checks suggested everything was OK.

You can only hope the repairer did all the right checks before handing the vehicle back to you. If you believe that was the case, then subsequent failures have to be put down to bad luck.

Cost of repairs - Hard one to answer really. The head is normally sent for checking (straightness, hardness and cracks). The worse scenario is a new cylinder head which could take the repair close to or above two thousand dollars as a guess. The repairer should be recommending a radiator clean / inspect and a possible water pump and cam belt replacement this time around also in my opinion.