Detroit Diesel — Removal of Exhaust Valve Spring (Cylinder Head Installed)
Repair & overhaul
From a Detroit Diesel service manual — check it applies to your exact model before use.
Before you start
- Remove loose clothing, jewelry; tie back long hair near an operating engine.
- Do not turn crankshaft to the left with a wrench on the crankshaft bolt.
Procedure
- Remove and clean the valve rocker cover; discard gasket.
- Crank engine to bring valve and injector rocker arms horizontally in line.
- Disconnect and remove fuel pipes; cover injector openings with shipping caps.
- Remove the two bolts holding rocker arm shaft brackets.
- Remove brackets and shaft.
- Remove the exhaust valve bridge.
- Remove cylinder block air box cover to observe piston travel.
- Turn crankshaft until piston is at top of its stroke.
- Thread valve spring compressor adaptor J 7455-7 into rocker arm bracket bolt hole.
- Compress valve spring and remove the two-piece tapered valve lock.
- Release tool and remove spring cap, valve spring and spring seat.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Source: Detroit Diesel 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.