a) Injection pump control rack wrongly set (3b,c). Load the engine, if possible.
Block fuel supply, e.g. by means of fuel filter three-way cock.
- Diesel fuel control rack blocked or incorrectly set
b) An overspeeding engine is hard to stop. Therefore, check regularly the adjustment of the control mechanism (the injection pump rack positions):
1) the stop lever being in stop position or the overspeed trip device being tripped and the speed governor at max. fuel admission
2) the stop lever and the overspeed trip being in work position and the speed governor in stop position.
This control should be done always when the control mechanism or the injection pumps have been touched.
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50-200513-06 Operating Troubles 08
W50DF 08 - 5
08.2 Emergency operation
08.2.1 Operation with defective air cooler(s)
If the water tubes of an air cooler are defective, the cooling water may enter the cylinders. If water or water mist flows out of the drain pipe at the bottom of the cooler housing, check whether it is raw water or condensate. If condensate, reduce cooling (see chapter 03, Fig 03-2). If raw water, stop the engine as soon as possible and fit a spare cooler.
In case of no available spare cooler, the following procedure can be carried out as an emergency solution:
a) Dismantle the cooler for repair and blank off the opening in the charge air cooler housing. Shut off the water supply and the return pipes. Repair the cooler, e.g. by plugging the leaking tubes.
b) If there is not time enough to remove the defective cooler to re-pair it, then only shut off the water supply and the return pipes.
c) Operating with a partially plugged, shut-down or removed air cooler.
The engine output must be limited and normal full load exhaust temperatures must not be exceeded. The turbocharger may surge before the admissible exhaust temperatures are reached. In such a case, engine load must be reduced further to avoid continuous surging.
08.2.2 Operation with defective turbocharger(s)
A defective turbocharger is to be treated in accordance with the service instructions given in the turbocharger instruction book (blocking of rotor, blanking of turbocharger etc.)
If one of the turbochargers on a V-engine is defective and must be blocked, the other charger has to be blocked too. The air connection between the turbocharger and the air cooler housing should be removed and the engine will operate as a naturally aspirated engine. Available load from the engine with blocked turbocharger(s) is about 20 % of full load. The engine output must, however, be limited so that the normal full load exhaust temperatures are not exceeded.
Note! Both turbochargers on a V-engine must be blocked or blanked in case of one charger is defective and blocked
08 Operating Troubles 50-200513-06
08 - 6 W50DF
08.2.3 Operation with defective cams
If the camshaft piece with damaged cams cannot be removed and replaced by a new one, the engine can be kept running by the following measures:
a) Injection pump cams:
Slight damage:
Set the injection pump control rack to zero position and lock it by using the limiter tool 863001.
Bad damage:
Remove the fuel injection pump. See chapter 16.
Attention! Concerning vibrations, see sec. 08.2.5.
When operating with a shut-off injection pump over a long period, the valve push rods of the inlet and outlet valves are to be removed, and the indicator valve on the respective cylinder is to be opened once an hour to allow any accumulated oil to escape.With one cylinder out of operation, reduce load to prevent exhaust temperature of the remain-ing cylinders from exceedremain-ing normal full load temperatures.
b) Valve cams
Shut off the fuel injection to the cylinder concerned, see chapter 16.
Remove the valve push rods and cam followers of the cylinder. Replace the tubes covering the push rods.
Run the engine with reduced load to prevent the exhaust tempera-tures from exceeding their respective normal full load temperatempera-tures.
08.2.4 Operation with removed piston and connecting rod
In case of such damage on piston, connecting rod or big end bearing that cannot be repaired, the following can be done to allow emergency operation:
1 Remove the piston, the connecting rod and the big end bear-ing.
2 Cover the lubricating oil bore in the crank pin with a suit-able hose clip, and secure it.
3 Fit the cylinder head without mounting the valve push rods.
4 Prevent starting air entry to the cylinder head by removing the pilot air pipe.
5 Set the injection pump fuel rack to zero position and lock it using the limiter tool 863001.
50-200513-06 Operating Troubles 08
W50DF 08 - 7
Run the engine with reduced load to prevent the exhaust temperatures from exceeding their respective normal full load temperatures. If the turbocharger(s) surges, reduce load further to avoid continuous surg-ing. Operation with removed piston and connecting rod, from one or more cylinders, should be performed only in absolute emergency conditions when there are no other means of proceeding under own power.
08.2.5 Torsional vibrations and other vibrations
When running the engine with one cylinder, or more, out of operation, the balance of the engine is disturbed and severe, or even dangerous, vibrations may occur. The vibration conditions are, in practice, depen-dant on the type of the installation.As a general advice, when there are cylinders out of order:
1 Reduce load as much as possible.
2 Keep the speed in a favourable range (completely depend-ing on the type of installation).
If one or several pistons are removed, lowest possible speed should be used.
08 Operating Troubles 50-200513-06
08 - 8 W50DF