Coolant Not Flowing D-4d

[lee_123]

I have recently purchased a 2002 Yaris 1.4 D-4D. The heaters have not been working so I put it into my local garage. The mechanic found that the water was not flowing round the engine.

He has tried a new pump and thermostat but this has not solved the problem. The car is running well and there is no signs of the head gasket going:

The car does not lose water,

There is no loss of power.

The oil looks okay.

There does not appear to be exhaust fumes leaking into the water.

Can someone please suggest any possible reasons for this problem.

Thanks!