Mitsubishi — Measuring the compression pressure
Testing & diagnosis · Cylinder compression
From a Mitsubishi service manual — check it applies to your exact model before use.
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Before you start
- Measure the compression on all cylinders.
- Compression pressure may vary depending on engine rpm; check engine rpm when measuring.
Procedure
- Remove the injection nozzle from the cylinder on which compression pressure is to be measured.
- Attach gauge adaptor (36791-00100) to the cylinder, and connect the compression gauge to the adaptor.
- Crank the engine by means of the starter, and read the compression gauge when engine begins to run at specified speed.
- If compression pressure is lower than the repair limit, overhaul the engine.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Compression pressure: 30 kgf/cm² (427 psi) [2.9 MPa] at 300 rpm; repair limit 27 kgf/cm² (384 psi) [2.6 MPa]
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.