Why Won’t My Case SV216 Roller Start Despite Cranking

[MikePhua]

The SV216 and Its Common Rail Diesel System
The Case SV216 single drum vibratory roller is a heavy-duty soil compactor designed for road building, site preparation, and infrastructure work. With an operating weight of over 16,000 lbs and a drum width of 84 inches, the SV216 is powered by a Cummins QSB4.5 Tier III engine featuring a common rail fuel injection system. This electronically controlled setup allows precise fuel delivery, improved emissions, and better cold starts—but it also introduces diagnostic complexity when the machine cranks but fails to start.
Unlike older mechanical injection systems, common rail engines rely on high-pressure fuel pumps, electronic injectors, and sensor feedback to initiate combustion. If any part of this chain fails, the engine may crank without firing.
Initial Checks for No-Start Conditions
When faced with a crank-no-start issue, operators should begin with the following:

• Battery voltage: Ensure a minimum of 12.4V at rest and 10.5V during crank. Low voltage can prevent injector activation.
  
• Fuel delivery: Check that the lift pump is supplying fuel to the high-pressure pump. Air in the lines or clogged filters can starve the system.
  
• ECM power and ground: Verify that the engine control module receives power and has a clean ground. A failed relay or corroded terminal can disable injector signals.
  
• Crankshaft position sensor: This sensor tells the ECM when to fire injectors. If faulty, the engine will crank endlessly without ignition.
  

One technician noted that the SV216’s Cummins engine uses a two-wire crank sensor mounted near the flywheel housing. If damaged or unplugged, the ECM won’t initiate fuel injection.
Fuel System Diagnostics and Pressure Testing
The common rail system requires minimum 5,000 psi at the rail to start. If the high-pressure pump is weak or the pressure relief valve is stuck open, the engine won’t fire. To test:

• Install a fuel rail pressure gauge or use diagnostic software
  
• Monitor pressure during crank cycle
  
• Check for injector leak-off using return line flow tests
  

If pressure builds slowly or fails to reach threshold, inspect the high-pressure pump, fuel control actuator, and rail sensor.
Electronic Faults and Safety Interlocks
Modern rollers include safety interlocks tied to seat switches, parking brakes, and throttle position. If any of these inputs are misread by the ECM, it may inhibit starting. For example:

• Seat switch failure may prevent fuel solenoid activation
  
• Throttle stuck above idle can trigger a no-start condition
  
• CAN bus errors between the dash and ECM may block injector signals
  

Use a diagnostic scanner compatible with Cummins Tier III engines to retrieve fault codes. Codes like SPN 94 FMI 2 (low rail pressure) or SPN 132 FMI 9 (injector circuit fault) can guide repairs.
Field Repair Strategy and Recommendations
To restore starting function:

• Replace both fuel filters and bleed the system thoroughly
  
• Inspect and clean all ECM connectors and grounds
  
• Test crank sensor resistance and replace if out of spec
  
• Verify fuel rail pressure during crank
  
• Check injector wiring for continuity and shorts
  

If no diagnostic tool is available, a manual pressure gauge and multimeter can still reveal most faults. In one case, a roller in Ghana was revived by replacing a corroded ECM ground strap and bleeding the fuel system after filter change.
Conclusion
A Case SV216 roller that cranks but won’t start is likely suffering from fuel pressure loss, sensor failure, or electronic interlock issues. By methodically checking voltage, fuel delivery, and ECM inputs, operators can isolate the fault and restore operation. The SV216’s Cummins common rail engine is powerful and efficient—but demands clean fuel, strong electrical connections, and precise sensor feedback to come alive.