During the startup of a diesel engine by the compressed air, after opening the main starting valve, the crankshaft is not turned or swings, not making a complete revolution. What could be the cause
The following possible causes to be investigated:
- The pressure of starting air in starting cylinders is insufficient or the reducing valve on a pipeline of starting air is faulty. Pump up air to the required pressure, examine and adjust a reducing valve.
- Excessive wear of piston rings. Check piston rings through scavenging ports (for the 2-stroke engine) or pull out random piston for inspection. Replace failed piston rings.
- The main starting valve is jammed. Check and rectify.
- Stuck in open position or leaky air starting valve(s). Check and replace faulty valves.
- Jammed slide valves in the starting air distributor. Open and check the distributor internally. Replace faulty parts.
- Starting air valve(s) seat is leaking. Check and lap the seating surface or replace gasket.
- Incorrect valve opening/closing timings, incorrect tappet clearances, valves hang. Check and adjust as per maker's manual.
- Pipelines from the starting air distributor of air are сhoked. Clean pipes
- Indicator valves are open. Close indicator valves.
- After docking, the packing gland of a stern tube is overtightened which the shaft from rotation. Adjust tightening as per Manual.
- The propeller blocked, touches an obstruction or has a rope wrapped on it. Check and release the propeller from obstructions.
- Starter cant reach deigned speed. Inspect starter, recharge batteries.