PACCAR MX-13 Injector Hold-Down Bolts
The MX-13 uses a clamp-style injector hold-down. Proper torque prevents injector lift and combustion gas blow-by past the injector sleeve. These are torque-to-yield bolts — replace on every removal. The MX-13 injector sleeve is a common failure point when injectors are improperly torqued.
Important: These torque specs are reference values. Always verify against your OEM service manual for your specific engine serial number and build date. Torque-to-yield bolts must be replaced — never reused.
Torque Specifications
| Step | Torque Value | Notes |
|---|---|---|
| Lubrication | N/A | Apply clean engine oil to bolt threads and under bolt head. |
| Pass 1 — Snug | 15 ft-lbs (20 Nm) | Hand-snug all injector clamp bolts before torquing. |
| Pass 2 — Final | 22 ft-lbs (30 Nm) | Replace bolts — torque-to-yield. Do not reuse. |
Related Fault Codes
Click any fault code to open the AI Diagnostic Engine for guided troubleshooting.
Frequently Asked Questions
What is the torque spec for PACCAR MX-13 injector hold-down bolts?
MX-13 injector hold-down bolts torque to 22 ft-lbs (30 Nm) after an initial snug pass at 15 ft-lbs. Lubricate threads with clean engine oil.
Do MX-13 injector bolts need to be replaced?
Yes — MX-13 injector hold-down bolts are torque-to-yield and must be replaced every time they are removed.
What is the MX-13 injector sleeve failure risk?
Improperly torqued injectors on the MX-13 can cause injector sleeve damage, requiring sleeve replacement — a significantly more expensive repair than injector replacement alone.
What fault codes are related to MX-13 injector issues?
Common related fault codes include SPN 157 FMI 18 (fuel rail pressure low), SPN 651 FMI 5 (injector circuit open), and SPN 651 FMI 6 (injector circuit short).