Detroit Diesel 60 Series Cam Lash Adjustment Procedure: J-46303 Professional Guide
By Blogdashfdhd Adminvsbgfsf •
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