Detroit Diesel — Exhaust Valve Clearance Adjustment (Cold Engine, Two-Valve Cylinder Heads)
Adjustments · Exhaust valves
From a Detroit Diesel service manual — check it applies to your exact model before use.
Before you start
- Do not turn the engine in a left-hand direction with a wrench on the crankshaft or camshaft bolt at the front of the engine.
Procedure
- Place the governor stop lever in the no-fuel position.
- Clean loose dirt from valve rocker covers, remove covers, and cover drain cavities in cylinder head.
- Rotate crankshaft with starting motor or barring tool J 22582 until injector follower is fully depressed on cylinder to be adjusted.
- Loosen the exhaust valve rocker arm push rod lock nut.
- Place a .013 in feeler gage J 9708 between valve stem and rocker arm; adjust push rod for a smooth pull.
- Remove feeler gage; hold push rod with 5/16 in wrench and tighten lock nut with 1/2 in wrench.
- Recheck clearance: .011 in feeler gage passes freely, .013 in gage does not pass.
- Adjust remaining valves in the same manner.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- .013 in cold setting
- .011 in gage must pass
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.