Paxman Ventura

Paxman Ventura
Overview
ManufacturerDavey, Paxman & Co
DesignerGeoffrey Bone[2]
Also calledYJ
Production1960 (1960)–1992 (1992)[1]
Layout
Configuration60° vee: V6, V8, V12 or V16[3]
DisplacementV6: 39.42 litres (2,410 cu in)
V8: 52.56 litres (3,210 cu in)
V12: 78.84 litres (4,810 cu in)
V16: 105.12 litres (6,410 cu in)
Cylinder bore7.75 inches (197 mm)[2][1]
Piston stroke8.50 inches (216 mm)[2][1]
Cylinder block materialCast iron
Cylinder head materialAluminium alloy
ValvetrainOHV, 4 per cylinder[2]
Compression ratio13:1
Combustion
Operating principlefour-stroke turbo-charged high-speed diesel[3]
Fuel system2x CAV monobloc fuel injection pump (4x on V16), 11,500 psi (790 bar) (total) direct injection[2]
Fuel typediesel
Output
Power outputV12: 1,200–1,500 brake horsepower (890–1,120 kW; 1,200–1,500 PS) at 1,500 rpm
V16: 1,600–1,870 brake horsepower (1,190–1,390 kW; 1,620–1,900 PS) at 1,500 rpm
Chronology
PredecessorPaxman YH, direct injection medium-speed diesel
SuccessorPaxman Valenta

The Paxman Ventura is an internal combustion diesel engine for railway locomotives, built by Davey, Paxman & Co.

The type YJ or Ventura was developed in the mid-1950s as Davey, Paxman's first high-speed diesel engine.[4] With a view to the forthcoming modernisation and dieselisation of British Railways (BR), it was intended as a successor to Paxman's existing medium-speed engine, the direct injection YH.[5] High-speed engines offered higher power-to-weight ratios, which in turn allowed locomotives to have a lower axle loading and greater route availability. The YJ was to have a weight of less than four tons for a 1,200 horsepower (890 kilowatts; 1,200 metric horsepower) V12, with versions of V6, V8, V12, and V16 configurations.[2][4] Their construction and reliable use though required more sophisticated manufacture than previously, with better metallurgy and balancing of the moving parts for faster running and a stiffer crankcase to avoid vibration.

A total of 1098 engines were built by Paxman in Colchester, England (147 V6, 190 V8, 426 V12, and 335 V16); a further 37 were built under licence in Italy by Motori Breda of Milan for the D.343 Class locomotives of the Italian State Railways.[1]

  1. ^ a b c d Cite error: The named reference Carr-Ventura was invoked but never defined (see the help page).
  2. ^ a b c d e f Carr, Richard (28 September 2022). "Ventura (also known as the YJ)". PaxmanHistory.org.uk. Richard Carr's Paxman history pages. Retrieved 15 August 2023.
  3. ^ a b Bolton, William F. (1963). The Railwayman's Diesel Manual (4th ed.). pp. 79–80.
  4. ^ a b Evans, R.K. (May 1964). "The Ventura – Paxman's high-speed engine". Modern Railways. pp. 328–329.
  5. ^ Diesel Manual (1963), pp. 49–53.