Head gasket replacement in the UK typically costs £900–£2,500 depending on engine. On older cars worth less than £2,500, it's usually not worth fixing. K-series Rover engines, BMW N47 diesels and PSA 1.6 HDi engines are notorious for head gasket failure and often uneconomic to repair.
Head gasket failure is the diagnosis nobody wants. Here's how to decide whether to fix or scrap.
What it costs
Inline 4-cylinder (most cars): £900–£1,800 fitted at an independent. V6/V8 or DOHC: £1,500–£2,500+. If the head is also cracked, add £400–£800 for skim and pressure test, or £700+ for a replacement head.
What's included
Head off, gasket replaced, head pressure-tested and skimmed (small distortion), new head bolts (always — they're torque-to-yield), coolant flush, oil + filter, possibly cambelt if disturbed.
When to scrap instead
If the car is worth less than £2,500, the maths usually doesn't work. Unless it's a low-mileage example or sentimental, sell as spares-or-repair on eBay (£300–£700 typical for a runner with HG fail) and buy something else.
How to confirm before paying
Block test (£20–£40) detects exhaust gases in coolant. Compression test confirms cylinder seal. Mayonnaise under the oil cap or white smoke from exhaust = strong indicators but not conclusive on their own.
Head gasket repair cost UK by engine type
Small 3- and 4-cylinder petrols (Fiesta, Corsa, Yaris, Polo): £900–£1,300 fitted at an independent. Common 4-cylinder diesels (1.6 HDi, 2.0 TDI, 1.5 dCi): £1,100–£1,700, more if the injectors fight coming out. Twin-cam and turbo petrols (Focus ST, Golf GTI, Mini Cooper S): £1,300–£1,900. V6 and V8 engines, where both heads usually come off: £1,800–£3,000+. A main dealer will typically be 1.5 to 2 times these figures. The labour is the big part — 8 to 15 hours on most cars — and that's why the price barely changes whether the gasket itself is £30 or £120.
Signs it really is the head gasket (and not something cheaper)
Losing coolant with no visible leak, white sweet-smelling smoke that hangs about, bubbles in the expansion tank with the engine running, the top hose rock-hard soon after starting, and overheating on a long climb are the classic signs. Mayonnaise under the oil cap on its own is not proof — short trips in a Scottish winter cause that on healthy engines. Before paying for a head job, get a combustion leak (block) test for around £30–£50 and a cooling system pressure test. A failed water pump, cracked expansion tank or a sticking thermostat can look very similar and cost £80–£400 instead of £1,500.
Does head gasket sealant work?
Honestly, sometimes — as a short-term get-you-home on a minor weep between a coolant passage and the outside of the engine. It will not fix a gasket blowing combustion gas into the cooling system, and the cheap stuff can block the heater matrix and radiator, adding to the final bill. If the car is worth £800 and you only need it to last until you replace it, a quality sealant (£20–£40) is a reasonable gamble. If you intend to keep the car, pay for the proper repair.
Bob's honest advice before you say yes
Ask for a written quote that lists the head skim and pressure test, new head bolts, coolant, oil and filter, and whether the cambelt and water pump are being done while it's apart (on a belt-driven engine they should be — you've already paid the labour to get there). Ask what happens if the head is found cracked once it's off. A good garage will tell you that possibility up front, not after the engine is in bits.
Beyond the gasket, what other parts often need replacing with a blown head gasket and how does that affect the overall cost? — A blown head gasket rarely comes alone. You're almost certainly looking at new head bolts, engine oil, coolant, and an oil filter. Often, the cylinder head itself will need skimming or even replacing if warped, and sometimes the thermostat and water pump are replaced as preventative measures whilst everything's apart. These extra parts can easily add £150-£500 to the bill, pushing the total towards the higher end of the £800-£2000 bracket, depending on your car.
Can I drive my car with a blown head gasket to a garage, or will I cause more damage? — Honestly, it's a huge risk. Driving with a blown head gasket can quickly lead to catastrophic engine damage. Coolant mixing with oil destroys lubrication, and overheating can warp the cylinder head beyond repair, or even seize the engine entirely. If you suspect a blown gasket, the safest and often most cost-effective option in the long run is to arrange recovery. The cost of a tow is usually far less than a new engine.
Will a blown head gasket cause my car to fail its MOT, and what should I check for before taking it in? — Absolutely, yes. A blown head gasket will almost certainly cause an MOT failure. Common failure points include excessive exhaust smoke (blue or white), oil leaks, coolant leaks, and engine warning lights. Before your MOT, check your oil for a 'milky' consistency, look for oil in your coolant reservoir, and observe your exhaust for unusual smoke. These are tell-tale signs of a failing head gasket and will need addressing before your car stands any chance of passing.
Will K-Seal or BlueDevil actually fix a blown head gasket? — Sometimes — for very small leaks. Most workshop mechanics see them as a temporary patch to limp a car to scrap. Don't bet long-term reliability on it.
Why is the head gasket so expensive to replace? — It's 6–12 hours of skilled labour to strip the top of the engine, plus the head almost always needs machining.
How much is a head gasket repair in the UK on a typical family car? — On a typical 4-cylinder family car like a Focus, Golf or Astra, expect £1,000–£1,700 at an independent garage, including head skim, pressure test, new bolts, coolant and oil. Main dealers usually charge £1,800–£3,000 for the same job.
Can I drive with a blown head gasket? — Only for very short distances, and only while watching the temperature gauge closely. Each overheat risks warping or cracking the head, which turns a £1,200 job into a £2,500 one or scraps the engine. If it's losing coolant fast or boiling over, stop and get it recovered.
A head gasket repair in the UK costs £900 to £1,800 fitted at an independent garage on most 4-cylinder cars, and £1,800 to £3,000 or more on V6 and V8 engines. Get a £30 to £50 combustion leak test first — a water pump or thermostat fault can look similar.
Answered by Bob — 32 years on the tools, DVSA-approved MOT centre, Birnam, Perthshire.