Table of contents: Preparation ↓ Launch ↓ Running-in ↓ Test drive ↓ Service intervals range from 1000 to…↓
Attention: The most critical moments in the "life" of a newly repaired engine are the first few seconds of operation. Preparation makes the difference between a smooth step into later "life" and a more abrupt transition. The necessary conditions for starting the engine are the following: the engine must be filled with engine oil and coolant and the valve timing must be set.
Preparation
After installing the engine, add engine oil to the required level.
If the camshaft has been replaced, it is recommended that the engine be run at high idle speed for several minutes. The battery must be fully charged, and the ignition timing must be set as accurately as possible.
When the engine starts and runs for the first 20 minutes of "break-in", about 500 liters of deadly carbon monoxide will come out of it. Therefore, it is necessary to ensure good ventilation of the room where the car is located, i.e. open all windows and doors. Carbon monoxide is heavier than air and can accumulate in a confined space for several hours. The first few minutes of engine operation are especially dangerous if you are working in a closed garage.
Launch
At this point, the repaired engine is ready to start. Connect a timing light, tachometer and oil pressure gauge to the engine. If the engine has hydraulic valve lifters, remove the valve covers before starting. Many reputable auto shops have spring clips that install on the rocker arms to repel oil while the engine is running and the valves are being adjusted. If you don't use these clamps, the oil will spray everywhere.
It's tempting to use a special starting fluid when starting the engine, but using too much of it can damage the engine. It is even more potentially dangerous when the engine has just been rebuilt.
Bleed the fuel system. To do this, on engines with electronic fuel injection, turn the ignition on and off several times.
Caution: Pouring fuel into the intake manifold to start the engine is very dangerous.
Turn on the starter and listen for signs of life from the engine.
If the engine makes popping noises or backfires in the intake or exhaust manifolds, the ignition timing is incorrect. However, a few soft pops in the intake tract may simply indicate that a few drops of oil have entered the cylinders and the engine should start. If the engine does not start or runs very poorly after starting, refer to the appropriate chapter.
For both the amateur and the professional, it can be confusing to reconnect all the pipes, wires and hoses that were disconnected when the engine was removed. Numbering, marking, and even photographing the engine compartment before removing the engine will help you navigate this mess more easily later.
[Information copied from the website NissanBook.ru]
Running-in
Once the engine starts, immediately increase its speed to 1500-2000 rpm. Stabilize the engine speed. The camshaft and valve lifters will better bond with each other if the engine isn't allowed to idle for the first 20 minutes of its new life. The camshaft receives significantly less oil at idle. The revs should be slightly higher to ensure the camshaft and tappets are well lubricated. Also, do not change the engine speed abruptly during the first 20 minutes of its operation. Failure to maintain engine speed at a relatively constant level will result in unwanted loads on new parts, tighter tolerances, and parts that have not yet been run in. During the 20-minute "break-in" period, it is necessary to constantly monitor the oil pressure and engine temperature. If any abnormal values occur, then smoothly switch the engine to idle mode, turn off the engine and eliminate the cause of this phenomenon.
Carefully check for oil, coolant, power steering fluid, and automatic transmission (CVT) fluid leaks.
After the 20-minute "break-in" period, slowly return the engine to idle and let it idle long enough to check the ignition timing and idle speed.
Test drive
Now everything is ready for the test drive. Start with a short drive near the repair site. Since the car has not been driven for a long time, listen carefully for unusual noises and constantly monitor the coolant temperature and oil pressure. For safety reasons, please take a travel companion with you. If the values on the gauges go beyond the permissible limits, immediately turn off the engine and determine the source of the problem.
Caution: Do not test drive until all removed parts have been installed and all systems are operating properly.
After the test drive, it is necessary to evaluate the values of vital engine parameters.
Disconnect the stroboscope and tachometer. If possible, position the oil pressure gauge so that it is visible while driving. If the pressure gauge hose is too short, remove the pressure gauge, check that the oil pressure warning light is working, and monitor it while driving.
Now you can take a longer test drive. During this trip, the likelihood of a malfunction in the ignition system circuit is directly proportional to the distance from your garage. Keep this in mind.
Once you return to the garage, check all wire harnesses. Check the oil level, make sure there are no oil leaks and repair them if necessary.
The same applies to the cooling system.
Once the test drive is completed and the hose clamps, drain plugs and oil pan bolts are tightened, the car can be driven for several days (or weeks) until the next maintenance. The driver should be aware of recent repairs and, while driving, carefully monitor the instruments and warning lights, and listen for unusual sounds.
Service intervals range from 1000 to 1500 km
Between 1,000 and 1,500 km the vehicle must undergo maintenance. Allow the engine to cool completely, preferably overnight. Loosen and retighten the cylinder head bolts, adjust the valve clearances using the appropriate techniques. Change the engine oil and oil filter. Check the tension of all belts and the tightness of the hoses. Check the oil level in the automatic transmission (CVT).
If all operations are completed and there are no traces of engine oil or coolant leaks left under the vehicle, then the engine repair can be considered successfully completed.