This 12-phase procedure uses the J-46303 checking fixture to accurately measure and set cam/valve lash on Detroit Diesel Series 60 engines—ensures optimal valve timing, reduced wear, and peak performance. Introduction: Accurate Cam Lash for Series 60 Performance The J-46303 fixture provides stable, repeatable measurement—key to correct lash settings and preventing valve train issues. Phase 1-4: Engine Preparation & Access Secure engine / vehicle – Hoist or stand support Remove rocker cover & accessories – Clear access to rockers Set engine to adjustment position – TDC on cylinder to check Install J-46303 fixture – Secure to cam/rocker area Phase 5-8: Lash Measurement Position feeler gauge or dial indicator – In fixture slot Check lash at base circle – Cam lobe lowest point Record measurement – Compare to Detroit spec Repeat for all valves – Rotate engine as needed Phase 9-12: Adjustment & Verification CRITICAL: J-46303 Lash Adjustment Keys Adjust lash screws to spec – Locknut torque to spec Recheck lash with fixture – Confirm after torque Reassemble rocker cover – Torque sequence Start & monitor engine – Check for noise/codes Critical Warnings: Lash Measurement Errors AVOID THESE DAMAGING MISTAKES: ❌ Hand-held gauge only – Inconsistent readings ❌ Wrong cam position – False tight/loose lash ❌ Skip recheck after torque – Lash shift ❌ Incorrect spec reference – Over/under adjustment ❌ No cold/hot check – Thermal change errors Why J-46303 Beats Hand-Held Measurement Hand-Held Risks: ❌ Gauge wobble → $1.5K+ wear ❌ Inconsistent angle → Bad adjustment ❌ Repeat failures → Rework losses J-46303 Advantages: ✅ Fixed stable platform ✅ Repeatable positioning ✅ 90%+ accuracy boost ✅ Fast consistent checks ✅ Prevents $7.5K–$25K issues ✅ Shop standard reliability Adjust Detroit 60 Lash Precisely. Optimal Efficiency. Reduced Wear. No Guesswork. Get J-46303 – $175.00