Buyer’s Guide — Bentley Mk VI
What to know before buying a Bentley Mk VI.
Overview
The Bentley Mk VI was produced from 1946 to 1952, with approximately 5,200 examples built. It was the first Bentley offered with a factory standard steel body, produced by Pressed Steel Company, though many were also fitted with bespoke coachwork by firms such as H.J. Mulliner, Park Ward, James Young, Hooper, and Franay. The car features a 4,257 cc (later 4,566 cc from 1951) inline-six engine with overhead inlet and side exhaust valves, mated to a four-speed synchromesh gearbox.
The Mk VI shares much of its mechanical underpinnings with the Rolls-Royce Silver Dawn, and many parts are interchangeable between the two. Standard steel-bodied cars are the most affordable, while coachbuilt examples — particularly drophead coupes — command significantly higher prices.
Model Variants
| Standard Steel Saloon | Factory body by Pressed Steel Company — most common, approx. 4,000 built |
| Small Bore (1946–1951) | 4,257 cc engine (3.5″ bore), earlier cars |
| Big Bore (1951–1952) | 4,566 cc engine (3.6″ bore), more power, sometimes called “4½ Litre” |
| Coachbuilt | Various body styles by Mulliner, Park Ward, James Young, Hooper, Franay and others — saloons, dropheads, fixed-head coupes |
What to Look For — Body & Chassis
| Inner Wings | Check for corrosion around the inner wing panels, particularly where they meet the bulkhead. Mud and moisture collect here and cause hidden rust. |
| Sills & Jacking Points | Inspect the sills carefully — they rot from the inside out. Jacking points should be solid, not soft or repaired with filler. |
| Boot Floor | The boot floor is prone to rust, especially around the spare wheel well. Lift the carpets and check thoroughly. |
| Door Bottoms | Standard steel body doors rust at the bottom edges. Check for bubbling paint or filler repairs. |
| Rear Wheel Arches | Check for corrosion and signs of poorly done repairs. These are a common rust area. |
| Chassis Frame | The chassis is substantial but inspect for corrosion at the spring hangers, outriggers, and where the body mounts attach. |
| Coachbuilt Bodies | If coachbuilt, check the timber frame beneath the aluminium panels. Rotten wood leads to loose or rippled panels. Rebuilding a timber frame is expensive and specialist work. |
What to Look For — Mechanical
| Engine | The inline-six is robust and long-lived if maintained. Listen for bottom-end rumble (worn mains or big ends) at idle. Oil pressure should be at least 20 psi at hot idle, 40+ psi when driving. Check for oil leaks at the rear main seal and rocker cover. |
| Cylinder Head | The inlet-over-exhaust valve layout means the exhaust valves run hot. Check for signs of overheating — discoloured paint on the manifold side, and ask about valve guide wear. |
| Cooling System | The cooling system is adequate if the radiator is clean and the thermostat working. Check for coolant leaks around the water pump and hose connections. Overheating usually means a clogged radiator core. |
| Gearbox | Synchromesh on 2nd, 3rd, and 4th. Worn synchros on 2nd gear are common — listen for crunching on downshifts. The gearbox is otherwise strong. |
| Rear Axle | Hypoid gears should be quiet. A whine or rumble from the rear indicates worn ring and pinion. Check for oil leaks at the pinion seal. |
| Brakes | Hydraulic front, mechanical rear with servo assistance. The servo is a mechanical unit driven off the gearbox — ensure it is working as the car is very heavy without it. Rebuild kits are available. Check brake drums for scoring. |
| Steering | Cam-and-roller type should have minimal play. Some free play is normal but excessive looseness means a worn steering box. Check king pins for wear — lift the front and rock the wheel top to bottom. |
| Suspension | Front independent with coil springs, rear semi-elliptic leaf springs. Check the rear spring gaiters — if the leather gaiters are split, the springs will be dry and the leaves will wear. Front shock dampers are adjustable from the steering wheel — make sure this control works. |
Electrical System
| Dynamo | 12-volt system with dynamo charging. Check charging rate with a voltmeter — should show 13.5–14V at fast idle. Dynamos can be rebuilt but many owners convert to an alternator for reliability. |
| Starter Motor | Separate starter motor with reduction gear. Should engage smoothly — grinding means a worn pinion or ring gear. |
| Wiring | Original cloth-covered wiring deteriorates over time. Check for brittle insulation, corroded connectors, and ensure all lights and instruments work. A full rewire is common on restoration projects. |
Parts Availability
Parts supply for the Mk VI is reasonable thanks to the active Rolls-Royce and Bentley enthusiast community. Many mechanical components are shared with the Rolls-Royce Silver Dawn. Key suppliers include Flying Spares (UK), Fiennes Restoration (UK), and various specialists worldwide. Rubber seals, brake components, and engine gaskets are readily available. Body panels for standard steel cars can be sourced but are not cheap. Coachbuilt body panels must be fabricated individually. Chrome trim and interior parts can be harder to find and expensive to restore.
What a Good One Should Feel Like
A well-sorted Mk VI is a refined, comfortable tourer that feels far more modern than its 1940s origins suggest. The engine should be smooth and quiet, pulling strongly from low revs with a deep, muted exhaust note. The gearbox should shift cleanly through all four speeds with no crunching. Steering will feel heavy at parking speeds but should lighten up on the move with a reassuring directness. The ride should be supple and well-damped — harsh or bouncy suspension indicates worn dampers or dry rear springs. The servo-assisted brakes should stop the car in a straight line without excessive pedal effort. Overall the impression should be of a solid, well-built machine that is effortless to drive at a relaxed pace.
Price Guide (Approximate, 2026)
| Standard Steel Saloon — Project/Needs Work | $25,000 – $45,000 |
| Standard Steel Saloon — Good Driver | $50,000 – $75,000 |
| Standard Steel Saloon — Excellent/Restored | $80,000 – $120,000 |
| Coachbuilt Saloon | $40,000 – $150,000+ depending on coachbuilder and condition |
| Coachbuilt Drophead Coupe | $150,000 – $400,000+ for desirable coachbuilders |
| Big Bore (4,566 cc) Premium | Typically 10–20% more than equivalent small bore cars |
Prices vary significantly based on provenance, coachbuilder, condition, and originality. Coachbuilt cars by H.J. Mulliner and Park Ward tend to command the highest prices. Cars with documented history sell at a premium.