Kubota — Injection Timing Adjustment
Adjustments · Injection Pump
From a Kubota service manual covering: Hurth HBW 100, Hurth HBW 125, Hurth HBW 150, Hurth HBW 250, Hurth HBW 35, Hurth HBW 50, M-25XPB, M-35B, M-40B. Check it applies to your exact model before use.
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Procedure
- Remove injection lines.
- Remove injection pump side cover, push in control rack by 0.2 in. (5 mm) and hold.
- Turn flywheel counterclockwise until fuel flows from delivery valve holder.
- Continue turning flywheel slowly, stop when fuel level at delivery valve holder begins to increase.
- Check if 'FI' mark (or timing angle lines) aligns with punch mark.
- If timing out of adjustment, readjust with shims.
Specs & values
- Shim A (two holes): 0.0079 in. (0.20 mm)
- Shim B (one hole): 0.0098 in. (0.25 mm)
- Shim C (without a hole): 0.0118 in. (0.30 mm)
- Shim 0.0059 in. (0.15 mm) changes timing approx. 1.5° (0.026 rad.)
Source: Kubota 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.