Engine - initial start-up after overhaul and reassembly

Engine removal and overhaul procedures / Engine - initial start-up after overhaul and reassembly

1 Refit the remainder of the engine components in the order listed in Section 9 of this Chapter, referring to Part A where necessary. Refit the engine (and transmission) to the vehicle as described in Section 2 of this Chapter. Double-check the engine oil and coolant levels and make a final check that everything has been reconnected. Make sure that there are no tools or rags left in the engine compartment.

2 Remove the spark plugs, referring to Chapter 1 for details.

3 The engine must be immobilised so that it can be turned over using the starter motor, without starting - disable the fuel pump by unplugging the fuel pump power relay from the relay board; refer to the relevant Part of Chapter 4 for further information.

Caution: If the vehicle is fitted with catalyst, it is potentially damaging to immobilise the engine by disabling the ignition system without first disabling the fuel system, as unburnt fuel could be supplied to the catalyst.

4 Turn the engine using the starter motor until the oil pressure warning lamp goes out. If the lamp fails to extinguish after several seconds of cranking, check the engine oil level and oil filter security. Assuming these are correct, check the security of the oil pressure switch cabling - do not progress any further until you are satisfied that oil is being pumped around the engine at sufficient pressure.

5 Refit the spark plugs, and reconnect the fuel pump relay.

6 Start the engine, but be aware that as fuel system components have been disturbed, the cranking time may be a little longer than usual.

7 While the engine is idling, check for fuel, water and oil leaks. Don’t be alarmed if there are some odd smells and the occasional plume of smoke as components heat up and burn off oil deposits.

8 Assuming all is well, keep the engine idling until hot water is felt circulating through the top hose.

9 Check the ignition timing idle speed and idle mixture setting as described in Chapter 1, then switch the engine off.

10 After a few minutes, recheck the oil and coolant levels as described in Chapter 1 and top-up as necessary.

11 On all the engines described in this Chapter, there is no need to re-tighten the cylinder head bolts once the engine has been run following reassembly.

12 If new pistons, piston rings or crankshaft bearings have been fitted, the engine must be treated as new, and run-in for the first 600 miles (1000 km). Do not operate the engine at more than three-quarter throttle, or allow it to labour at low engine speeds in any gear. It is also recommended that the engine oil and filter are changed at the end of this period.