Isuzu Truper - Isuzu Trooper
1. The maintenance instruction
2. Maintenance service
3. Engines
   3.1. Specifications of the engine and adjusting works
   3.2. An electric equipment and major repairs of engines
   3.3. The diesel engine of 2,8 litres
      3.3.1. Introduction
      3.3.2. Technical characteristics
      3.3.3. Compression check
      3.3.4. The top dead point of the piston № 1 (ВМТ)
      3.3.5. Backlashes of valves
      3.3.6. A cover of a head of cylinders
      3.3.7. A pulley of a cranked shaft
      3.3.8. Casings of a gear belt of a drive of a camshaft
      3.3.9. A gear belt of a drive of a camshaft
      3.3.10. Asterisks of a gear belt, натяжитель and intermediate pulleys
      3.3.11. Коромысла and pushers
      3.3.12. A head of the block of cylinders
      3.3.13. Oil картер
      3.3.14. The oil pump
      3.3.15. An oil radiator
      3.3.16. Epiploons of a camshaft and a cranked shaft
      3.3.17. A flywheel
      3.3.18. Fastenings of the engine / of a transmission
4. System of decrease in toxicity
5. Fuel system
6. Transmission and a running gear
7. A suspension bracket and a steering
8. Brake system
9. A body
10. A body electric equipment
11. Diagnostics of malfunctions
12. Electroschemes

Isuzu Trooper>> Engines>> The diesel engine of 2,8 litres>> Compression check

3.3.3. Compression check

Compression check

The prevention

For carrying out of this check it is necessary to use the special tester of a compression intended for diesel engines.

If the engine does not work or there is an ignition admission (the fuel system is serviceable), compression check can establish the reasons which have led to malfunction of the engine. If you check regularly can warn in advance any malfunction before there will be more serious signs.

For carrying out of check of a compression it is necessary to use a tester intended for diesel engines as pressure in the diesel engine much more exceeds pressure in the usual engine. The tester is connected to the adapter which is twisted in an aperture of a candle of prestarting heating or in an injector aperture.

Besides instructions which are applied on a tester, take into consideration the following:

  – The accumulator should be charged, the air filter should be pure and the engine should be разогрет to normal working temperature;
  – All candles of prestarting heating should be unscrewed before inspecting;
  – Unscrew a fixing nut and disconnect a plug of a socket from the locking valve of the injecting pump to prevent fuel injection.

1. Owing to especial properties of system of fast warming up of the engine it is necessary to disconnect the throttle valve of system from a collector to spend exact check of a compression.
2. For this purpose ослабьте fixing clips also lift the receiver, connecting the throttle valve with an intermediate metal cooler.
3. Disconnect vacuum hoses from the throttle valve, having taken into consideration a correct arrangement of hoses.
4. Ослабьте a clip, крепящий a tube of the throttle valve to a collector.
5. Unscrew fixing bolts and disconnect the throttle valve from an inlet collector.
6. Twist an adapter in the first cylinder and connect to an adapter the pressure gauge.
7. Turn a cranked shaft of the engine by means of a starter; after one or two turns pressure of a compression should increase to a maximum, and then be stabilised.
8. Write down the highest value of which has reached pressure.
9. Repeat check on the remained three cylinders, writing down value of the highest pressure for everyone.
10. In all cylinders pressure should be approximately identical;
The difference more than in 2 bar between any two cylinders means malfunction.
11. Consider that in the serviceable engine the compression should accrue quickly; the weak compression at the first step of the piston after which slow gradual increase of pressure follows during the subsequent steps, means that piston rings are worn out.
12. The weak compression at the first step which does not accrue during the subsequent steps, means that there is a leak through valves, or the lining of a head of cylinders (the reason can be as a crack in the head) is broken through.
13. The deposit on the bottom parts of heads of valves can become the reason of a low compression too.

The prevention

The reason of a low compression is more difficult for defining in diesel engines, than in the petrol. The method of damp check when in cylinders the oil small amount is filled in, in this case is unacceptable, as there is a risk of that oil will settle in вихрекамере or in deepenings of a head of the piston instead of proceeding to piston rings.

14. Though in exact sizes of pressure of a compression are not resulted, you can accept that fact for a management that, if pressure in any of cylinders is less 20 bar, it is the sufficient reason to consider the cylinder faulty.
15. Upon termination of check connect a plug of a plait of wires in a nest запорного the valve of the injecting pump and screw in candles of prestarting heating.
16. Establish the throttle valve of system of fast heating of the engine into place, having checked up that all hoses and tubes are connected correctly.

Check on presence of leaks

Check on presence of leaks is necessary to measure pressure at which there is a leak of compressed air from the cylinder.

This check is alternative to check of a compression and is much more effective than it as air leaving under pressure allows to define easily a leak place (piston rings, the valve or a lining of a head of cylinders).

The equipment on presence of leaks is usually inaccessible to check carrying out to the simple motorist, therefore, if necessary, check in specially equipped workshops.