How Much Does a Head Gasket Repair Cost?

The head gasket seals the cylinder head to the engine block, keeping combustion, oil and coolant apart. When it fails you get overheating, coolant disappearing with no visible leak, white smoke, a creamy emulsion under the oil filler cap, bubbles in the expansion tank or a heater that blows cold. The gasket itself costs little; the labour to strip the top of the engine, the machining the head often needs, and the parts that must be renewed on the way back together are what make this one of the dearest repairs a car can have. This guide explains what drives the cost and how to decide whether to proceed.

Norwich Tyres & Auto Service · 2 min read · Reviewed 18 September 2026

Why It Costs What It Costs

• Labour dominates. The cylinder head has to come off, which means draining the cooling system, removing the inlet and exhaust manifolds, the cambelt or chain, injectors on a diesel, and all the ancillaries in the way. On a simple four-cylinder engine that is a long day; on a V6, a transverse diesel or anything with a turbo it is considerably more.
• The head itself. An overheated aluminium head is often warped and must be pressure-tested and skimmed flat by a machine shop; a cracked head must be replaced, which changes the job entirely.
• Everything that comes off must be renewed properly. Head bolts are stretch bolts and are replaced, not reused. Manifold gaskets, cambelt and tensioner (if the engine has one), coolant, oil and filter, and often the thermostat and water pump are all done while the engine is apart, because doing them later means doing the labour twice.
• Collateral damage. Overheating that caused the gasket failure may have damaged the head, the liners or the pistons. That is why we diagnose before quoting rather than promising a gasket will fix it.

Is It Really the Head Gasket?

Not every overheating engine has a failed head gasket, and not every emulsion under the oil cap is a disaster (short-journey cars often show a little condensation there). Before anyone quotes a head gasket, the coolant system should be pressure-tested, the expansion tank sniff-tested for combustion gases, the oil inspected properly and the thermostat, radiator, water pump and fan checked. A stuck thermostat or a failed water pump is a fraction of the cost and is frequently the real fault. See cooling system repair and the overheating guide.

Head Gasket Sealants

Bottle sealants are sold as a cheap fix and occasionally buy a few weeks on an old car that is about to be scrapped. They also block heater matrices, radiators and coolant passages and make the proper repair harder and dearer. We do not use them and would not advise them on any car you intend to keep.

Is the Car Worth It?

This is the honest conversation. On a recent, otherwise sound car the repair is clearly worth doing. On an older car the cost can approach or exceed its value, and the decision depends on what else it needs, how long you would keep it, and what replacing it would cost you. We will give you the diagnosis, the quote and a straight opinion, and if the answer is that the car is not worth it we will say so. A vehicle health check alongside the diagnosis shows what else is coming.

How We Quote It

Bring the car in, or have it recovered if it is overheating; do not drive an overheating engine, that is how a gasket job becomes an engine job. We diagnose properly, quote the actual repair on your engine including the machining and the parts that must be renewed, and proceed only with your approval. Call 07933 900901.

How to Get an Honest Quote

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