Mitsubishi S3L2 / S4L2 — Compression pressure measurement
Testing & diagnosis · Engine
For the Mitsubishi S3L2 / S4L2, from the Mitsubishi service manual.
Applies to: Mitsubishi S3L2, Mitsubishi S4L2
Before you start
- Be sure to measure the compression pressure on all cylinders.
- Check engine rpm at the time of measuring the compression pressure.
Procedure
- Check crankcase oil level is correct and air cleaner, starter and battery are normal.
- Bring engine to normal operating temperature.
- Move control lever to a position for shutting off fuel supply.
- Remove all glow plugs; install compression gauge and adaptor (ST332270) to the cylinder to be measured.
- Turn engine with starter and read gauge pressure at the instant the gauge pointer stops.
- If reading is below the limit, overhaul the engine.
Tools required
- Compression gauge and adaptor ST332270 Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Compression pressure SL: 30 kgf/cm2 (427 psi) [2 942 kPa] standard; SL2: 32 kgf/cm2 (455 psi) [3 138 kPa]; at 290 rpm
Full service-parts list: Mitsubishi S4L2 →
Source: Mitsubishi service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.