Kobelco Type 10 Excavator Hard Start When Hot? Troubleshooting Guide
Is your Kobelco SK350 struggling to start after working for hours? Why is hydraulic back pressure often the hidden culprit?
[IMAGE: Kobelco Monitor Service Menu Data]
1. Monitor Pressure Data
Check C-1 and C-2 high pressure during startup. If pressure is detected, the engine faces resistance, making it hard to fire up.
| Parameter | Normal Range | Abnormal Indicator |
| C-1/C-2 High Pressure | ~0-2 MPa (Startup) | >5 MPa (Back pressure) |
| B-Series Pilot Pressure | 3.0 MPa (at Idle) | <2.5 MPa (Stalling risk) |
| G-3 Engine Speed | >200 RPM | <150 RPM (Insufficient) |
2. Inspect Pilot Pump & Regulator
Ensure pilot pressure reaches 3.0 MPa at idle. Also, check the regulator yoke for wear or sticking, which causes incorrect pump strokes.
[IMAGE: Hydraulic Pump Regulator Inspection]
3. Unloading Solenoid Valves
Inspect, clean and repair the unloading solenoid valve on the eight-unit solenoid valve assembly to prevent residual pressure buildup during startup.
