PISTONS SIZE 050 (SET OF 4)

EARLY MBMBM201EARLY GPWGPWCJ2ACJ3ACJ5
Manual available
156,15 €
BTW: 27,10 €
SKU:  WO116702F
GTIN (EAN,ISBN): 15A

Set of 4 engine pistons dimension 0.050" (Ø=80.64mm), delivered with their pins.
Suitable for Jeep Willys MB, M38, M38A1, CJ2A, CJ3A, CJ3B, CJ5, CJ6, Hotchkiss M201 and Ford GPW

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War Dept specs from the original Technical Manual — click to open

Pistons Size 0.50 Oversize (Set of 4)

For L-134 Go Devil engine

Set of four oversize pistons (0.50/0.050 inch) for overhaul of the 134 ci L-head engine. These pistons are intended for cylinders bored to +0.50 oversize during rebuild to compensate for wear.

Application

L-134 engine with bored cylinders

Oversize

50 inch (0.050")

Contents

Set of 4 pistons

Bore diameter

175 inch (standard 3.125" + 0.050")

Features

  • Oversize pistons for bored cylinders
  • Size 0.50 inch (0.050") over standard
  • Complete set of 4 pieces
  • For L-134 "Go Devil" flathead engine
  • Compression height 2.1875 inch

★ Essential component for professional engine rebuild when cylinder boring requires +0.50 oversize.

Application

These pistons are intended for vehicles fitted with the 134 ci L-head engine where the cylinders have been bored 0.050 inch during rebuild. The categories in which this product appears list: Willys MB, Ford GPW, M201, CJ-2A, CJ-3A, CJ-3B and M38. Important: check the exact bore of your cylinders — the machinist determines during boring which oversize is required (standard, 0.010, 0.020, 0.030, 0.040, 0.050 or 0.060 inch).

Installation notes

Have your machinist bore and hone the cylinders with these pistons present — the piston-to-bore clearance is determined with a pull scale and cannot be established beforehand. Never simply ask to "bore 0.50 oversize" without supplying the pistons. Check piston orientation and connecting rod direction according to the technical manual.

Compatibility

These pistons fit L-134 engine blocks bored 0.050 inch oversize. They are NOT compatible with standard bore or other oversize dimensions. The L-134 engine came in both chain-driven (early MB/GPW) and gear-driven (late CJ) versions — pistons are identical for both types. Note: from +0.060 oversize onwards, one often switches to cylinder sleeves rather than further boring.

Historical context

The Willys L-134 "Go Devil" engine, designed by chief engineer Delmar "Barney" Roos, was the powerplant of the legendary WWII jeep and many post-war Willys vehicles. The engine was characterised by its robust simplicity and reliability under extreme conditions.

This description was generated automatically. Unsure about fitment? Contact us at info@willys.be.

⚠ Spotted an error in this description? Report it to info@willys.be

Restoration part — not a ready-to-fit product

This part is intended for the restoration of historic military vehicles. Fitting, aligning, deburring or reworking is part of that work and is inherent to the nature of these goods. Dimensional variation also exists between original vehicles.

Installation requires technical knowledge of the vehicle. Unsure whether this part suits your version? Ask us before purchase at info@willys.be.

COMPATIBLE_MODELS EARLY MB, MB, M201, EARLY GPW, GPW, CJ2A, CJ3A, CJ5
ALL_CATEGORIES : Piston,Rings & Bearings CJ2A, Pistons And Sleeve CJ3A, Piston,Rings & Bearings M38, Pistons And Sleeve - M38, Pistons And Sleeve CJ3B

This part fits:

ModelYears
Military jeeps
Willys MB (early)1941, 1942
Willys MB1942, 1943, 1944, 1945
Ford GPW (early)1942
Ford GPW1942, 1943, 1944, 1945
Hotchkiss M2011956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966
CJ series
Jeep CJ-2A1945, 1946, 1947, 1948, 1949
Jeep CJ-3A1949, 1950, 1951, 1952, 1953
Jeep CJ-51955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983

📐 Diagrams & technical drawings

From the original Technical Manual CJ2A_PL_1949 — Parts List — only for Willys CJ-2A / CJ-3A (1949)

Group 10-06 — Pistons and Pins
Group 10-06 — Pistons and Pins
Page 22–23

From the original Technical Manual TM 10-1513 — Maintenance Manual — only for Willys MB / Ford GPW (1942)

Engine — Block, Crankshaft, Camshaft, Pistons, Valves
Engine — Block, Crankshaft, Camshaft, Pistons, Valves
Page 18–37