Sourcing engine cylinder heads from China

Cylinder head duty and classification

Read from the UK Trade Tariff on 30 September 2026, heading 8409 covers parts suitable solely or principally for the engines of headings 8407 or 8408. This guide covers cylinder heads, including casting blanks, machined bare heads and assembled heads. See engine parts for the wider heading.

The relevant cylinder head lines carry 2% duty for goods from China. The supplied tariff record shows no anti-dumping or countervailing duties and no attached import controls on these lines. The residual codes also contain narrowly described suspensions for other products; those entries do not establish a suspension for an ordinary cylinder head. A cylinder head cover is a different product.

Match the engine type and supplied condition to the commodity code. The dedicated blank line applies only when its full material, construction and dimensional description is met. Ask your customs broker to check the drawing and assembly list before declaration. The duty and VAT guide explains landed-cost calculations.

Engine variant, casting and supplied assembly

Specify the original equipment part number, engine variant and drawing revision. Record the combustion chamber shape, coolant and oil passages, bolt pattern, injector or spark-plug position, and manifold interfaces. Agree the alloy, heat treatment, sealing-face finish and machining tolerances against the drawing.

Define whether the order is a casting blank, a machined bare head or an assembly with valves, guides, seats and camshaft components. List every included component and agree pressure-test acceptance criteria. Approve a measured sample and trial fit before releasing production.

Importers remain responsible for product safety after the product is placed on the market. Keep the casting batch, machining report and supplied assembly linked to the part number so a complaint can be investigated.

Worked duty example

Illustrative example, not a quote: Illustrative shipment of 140 diesel cylinder heads under 8409 99 00 90, invoiced at £28,000 free on board, with £3,000 of freight and insurance to the UK. The customs value is £31,000. Duty at 2% is £620. Import VAT at 20% is charged on the customs value plus duty, £31,620, so it is £6,324. Import taxes total £6,944; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £620 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Identity: check the part number, engine variant, casting marks and included components against the approved sample and order.

Casting: check alloy and heat-treatment records, inspect for cracks and porosity, and review pressure-test results for coolant and oil passages.

Machining: measure sealing-face flatness and finish, bolt locations, guide bores and valve-seat geometry against the drawing; trial-fit the mating parts.

Arrival: check machined faces for impact damage and corrosion, passages for swarf, and packaging labels for batch traceability. Use quality inspection to agree the inspection scope.

What goes wrong

A matching vehicle model does not prove that the head fits the engine variant. Different passages, sensor locations or combustion chambers can make a visually similar casting unsuitable. Compare the drawing and mating interfaces rather than accepting a supplier's interchange claim alone.

Porosity can cause leaks, while poor machining can leave sealing faces or valve seats outside the agreed tolerances. Chips left in passages and unprotected faces create further problems on arrival. Hold suspect stock apart and connect the defect evidence to its casting and machining batch.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For machinery and equipment, see machinery imports.