Allis-Chalmers — Valve adjustment
Adjustments · Valve rocker arms
From a Allis-Chalmers operator's manual covering: 16000MKII, 17000MKII, 21000MKII, 25000MKII. Check it applies to your exact model before use.
Procedure
- Operate engine until normal operating temperature is reached.
- Clean valve rocker covers and surrounding area.
- Remove rocker cover capscrews and covers.
- Crank engine until No. 6 intake valves begin to open.
- Adjust No. 1 valve bridge: loosen locknut, back off screw, press bridge, turn screw to contact valve stem, tighten locknut.
- Adjust rocker arm clearance: intake .015 in, exhaust .020 in.
- Recheck clearances to make certain they did not change.
- Repeat for remaining cylinders per table sequence.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Intake .015 in hot
- Exhaust .020 in hot
- Cold setting: intake .020 in, exhaust .025 in
Source: Allis-Chalmers operator's 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.