Ford Escort - engine overheating (I think)

[jordana]

We fixed the thermostat by ourselves but then the water pump started leaking.

Just before Christmas, we gave up and put the car in to replace the water pump and give it a service. £300 odd quid and 5 days later, the radiator hose started leaking.

We fixed the radiator hose but the engine kept overheating.

We took it back to the same mechanic as we thought he should have pressure tested it.

He said he did but has now said that the head gasket has a leak in it and that the cylinders are putting air into the cooling system creating airlocks and causing the car to overheat.

I have four questions.

What is he taking about? Shouldn't the cylinders be separate from the cooling system? What does the head gasket actually have to do with the cooling system?

Should he have picked this up when he fixed the cooling system and serviced the car?

Can we fix this ourselves and how would we get rid of the airlocks?

thanks in advance

 

[jonnyfishing]

The head gasket keeps the coolant and oil separate when they are circulated round the engine.it also seals the combustion chambers.When a rupture occurs in the gasket you have to remove the cylinder head to replace it. It is possible and most probable that the overheating caused the head to warp and caused the gasket to fail.The cost of the repair will be very costly,the cylinder head will need pressure testing and skimming,the valve seats also need checking for warpage,if so,they will need recutting.A new head gasket set and new head bolts must be used.If you have the tools and a place to work it is not beyond the D.I.Y.with a Haynes manual. To check for a blown gasket,remove the cap from the expansion bottle start the engine and watch for bubbles rising in the bottle.The exhaust will also discharge white smoke/steam to excess.

Good luck with it.