Coolant leaks and overheating are among the most common — and most dangerous — failures on Land Rover, Range Rover, and Jaguar vehicles. A small leak from a plastic crossover pipe or weeping water pump can escalate to a blown head gasket or seized engine within miles. UK drivers often ignore early warning signs until catastrophic damage occurs.
We specialise in comprehensive cooling system repairs with a key difference: we replace failed plastic components with upgraded aluminium crossover pipes that eliminate the factory design flaw permanently. Every repair includes full pressure testing, combustion leak testing, and a 12-month unlimited mileage warranty.
Stop immediately. Continuing risks warped heads & seized engine.
Aluminium upgrade eliminates plastic pipe failure forever.
Early identification prevents catastrophic engine damage. If your JLR vehicle exhibits any of these signs, immediate inspection is required.
If you see the temperature gauge in the red or receive an overheating warning, STOP IMMEDIATELY. Continuing to drive even a short distance can warp cylinder heads, blow head gaskets, or seize the engine entirely — turning a £500 cooling system repair into a £5,000+ engine rebuild. Arrange recovery or call us for urgent assessment.
We offer fixed-price cooling system diagnostics including pressure testing and combustion leak testing to identify the exact source before recommending repairs. No guesswork, no unnecessary parts replacement.
Book a DiagnosticOn 3.0L V6 (TDV6/SDV6) and 5.0L V8 (AJ126/AJ133) engines, factory plastic coolant crossover pipes sit deep in the engine "V" — beneath the intake manifold on diesels and under the supercharger on petrol V8s. Years of heat cycling make them brittle. They crack suddenly and dump coolant rapidly, often without visible warning until the engine overheats catastrophically.
We replace failed plastic pipes with upgraded aluminium crossover pipes — a permanent fix that eliminates this design flaw entirely. Main dealers typically replace with the same flawed plastic part that will fail again. We also replace all associated o-rings, seals, and coolant hoses while the intake/supercharger is removed, ensuring the entire cooling circuit is renewed.
Aluminium upgrade available for TDV6, SDV6, AJ126, and AJ133 engines. Not available for all variants — confirm applicability when booking.
Mechanical water pumps on AJ126 (3.0L supercharged) and AJ133 (5.0L V8) engines are notorious for premature bearing wear and weeping seals. Thermostat housings crack over time, causing slow leaks that worsen progressively.
Replace with OEM-quality water pumps (Gates, INA) and updated thermostat housings designed to resist cracking. Full cooling system pressure test before and after repair confirms leak-free operation.
Get a Fixed QuoteThe 2.0L Ingenium diesel and petrol engines have two distinct coolant-related failure modes requiring accurate diagnosis before repair.
Coolant leaks internally into the exhaust stream, burning as white smoke. Symptoms include frequent coolant top-ups with no visible external leak, sweet exhaust smell, and potential DPF contamination. Diagnosis via EGR cooler pressure test and combustion gas analysis.
Coolant seeps into the combustion chamber or oil system due to cylinder liner movement or block porosity. This is the worst-case scenario, often requiring engine rebuild or replacement. Diagnosis via combustion leak test (hydrocarbon detection in coolant) and borescope inspection.
If the block is porous or liners have slipped, we will advise on rebuild vs replacement options with transparent costing. Repairs quoted separately after full diagnostic report.
On supercharged 5.0L V8 engines (AJ133), complex cooling lines run beneath the supercharger assembly. Isolation valves and small coolant hoses fail over time, causing hidden leaks that require stripping the top end of the engine to access.
Full supercharger removal, replacement of all cooling valves, plastic connectors, and rubber hoses with upgraded components. Reassemble with new gaskets and seals. System pressure tested and bled before road validation.
This repair requires significant labour (supercharger removal). We always quote fixed price before proceeding and include all necessary seals and coolant in the price.
Accurate diagnosis prevents wasted labour and repeat visits. Our six-step process ensures every leak is correctly identified, properly repaired, and verified before handover.
We pressurise the system to identify the exact leak location — crossover pipes, water pump, hoses, EGR cooler, or radiator. Visual inspection alone misses hidden leaks.
Checks for blown head gasket or porous block by detecting hydrocarbons in the coolant. Critical step before recommending expensive head or block work.
Intake manifold or supercharger removed as needed to access failed parts. All associated components inspected while accessible.
Aluminium crossover pipes (where applicable), OEM-spec water pump, thermostat, hoses, and seals installed. No reusing worn components.
Cooling system flushed to remove contaminants and old coolant. Correct JLR-approved coolant refilled and system bled of air pockets.
Second pressure test confirms no leaks. Road test validates proper temperature control, heater operation, and fan cycling. Only signed off when flawless.
Transparent pricing by repair type. Diagnostic fee deducted from repair cost if you proceed. All prices include VAT unless stated.
| Repair Type | Typical Price Range (Inc. VAT) |
|---|---|
| Coolant System Diagnostic (Pressure Test + Inspection) | £99 – £149 (deducted from repair) |
| Plastic Crossover Pipe Replacement (Upgraded Aluminium) | £450 – £750 |
| Water Pump Replacement (AJ126/AJ133) | £350 – £550 |
| Thermostat Housing Replacement | £250 – £400 |
| EGR Cooler Replacement (Ingenium) | £450 – £700 |
| Supercharger Cooling Valve/Hose Replacement | £550 – £950 |
| Combustion Leak Test (Head Gasket/Block Diagnosis) | £120 – £180 |
Price disclaimer: Prices are estimates for standard repairs on typical JLR vehicles in good condition. Final fixed quote provided after diagnostic inspection. If porous block or slipped liners are found, we will advise separately on rebuild/replacement costs. Part numbers vary by VIN — confirm applicability before ordering.
Permanent fix for the common plastic pipe failure. Main dealers replace with the same flawed plastic — we eliminate the design weakness entirely.
No guesswork. We find the exact leak before touching a spanner. Prevents misdiagnosis and unnecessary part replacement.
Detects blown head gaskets or porous blocks before you waste money on partial repairs. Critical for Ingenium and high-mileage V6/V8 engines.
We know every cooling system failure point on TDV6, SDV6, AJ126, AJ133, and Ingenium platforms. Deep expertise built over hundreds of repairs.
Parts and labour fully covered on all cooling system repairs. Same assurance as a franchised dealer, without the price. Full terms →
Based in Billericay but serving the entire UK. Free collection and return on repairs over £500. Enclosed transport for non-drivable vehicles.
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Coolant contamination accelerates chain wear on Ingenium engines.
Don't wait until overheating causes catastrophic damage. Call now for priority assessment or book a diagnostic online.
Book Diagnostic Online WhatsApp the WorkshopDirect answers to common coolant leak and overheating questions.
The most common cause is failure of factory plastic coolant crossover pipes on TDV6, SDV6, AJ126, and AJ133 engines. Heat cycling makes them brittle over time, causing sudden cracks. Other causes include water pump bearing/seal failure, cracked thermostat housings, EGR cooler cracks (Ingenium), and degraded rubber hoses. We identify the exact source via pressure testing before recommending repairs.
Only very short distances to reach a specialist — and only if the temperature gauge remains normal and there's no overheating warning. If the gauge rises or a warning appears, stop immediately. Continuing risks warped cylinder heads, blown head gaskets, or complete engine seizure. The cost of recovery is negligible compared to engine replacement. Top up coolant only if safe to do so and monitor closely.
Typically £450–£750 including VAT for upgraded aluminium crossover pipes, depending on engine type and accessibility (V8 supercharged engines require more labour). This includes all associated o-rings, seals, coolant flush, and pressure testing. Final fixed quote provided after inspection. Aluminium upgrade eliminates the plastic pipe failure permanently.
Yes, significantly. Factory plastic pipes become brittle from heat cycling and crack unpredictably. Upgraded aluminium pipes are immune to this failure mode and provide a permanent fix. Main dealers typically replace with the same flawed plastic part — we offer the superior solution. Note: aluminium upgrades are available for most TDV6, SDV6, AJ126, and AJ133 applications but not all variants. Confirm applicability when booking.
A chemical test that detects hydrocarbons (combustion gases) in the coolant system. Presence of hydrocarbons indicates a breach between the combustion chamber and cooling system — typically a blown head gasket, cracked cylinder head, or porous engine block. This test is critical before committing to expensive head or block repairs, as it confirms whether the issue is internal (engine mechanical) or external (cooling component). Cost: £120–£180 including VAT.
Symptoms include unexplained coolant loss, white smoke from exhaust, coolant in oil (mayonnaise-like emulsion on dipstick), and overheating. Diagnosis requires combustion leak testing and borescope inspection. If confirmed, this typically requires engine rebuild or replacement. We provide a full diagnostic report and transparent quote for all options before proceeding.
Yes, particularly on AJ126 and AJ133 engines where water pump failure is well-documented. If you're already having timing chain or crossover pipe work done, replacing the water pump preventatively adds relatively little labour cost and avoids future breakdown. We'll advise based on mileage, age, and condition during inspection.
Simple repairs (thermostat, hose replacement): same day. Crossover pipe replacement: 1–2 days depending on engine. Water pump replacement: 1–2 days. Supercharger cooling valve/hose replacement: 2–3 days. Complex diagnoses (combustion leak testing, EGR cooler): 1 day for testing plus repair time. We confirm timeline when booking and update proactively if anything changes.
All cooling system repairs include a 12-month unlimited mileage warranty on parts and labour. If a repaired component fails within the warranty period, we rectify at zero cost. Warranty excludes consequential damage from pre-existing neglect (e.g., head gasket failure caused by prolonged overheating before repair). Full terms at /warranty.
Yes. Every cooling system repair includes a full flush to remove contaminants, old coolant, and debris. We refill with correct JLR-approved coolant specification and bleed the system thoroughly to eliminate air pockets. Proper bleeding is critical — trapped air causes hot spots and repeat overheating. This is included in all repair prices.
Call 0203 488 4649 or WhatsApp 07975 827 396 for urgent assessment. We'll identify the exact leak source, recommend the right fix (including permanent aluminium upgrades), and provide a fixed quote before any work begins. Nationwide collection available. 12-month warranty on all repairs.