Mazda 626

1991-1998 of release

Repair and car operation



Mazda 626

+ 1. Maintenance instruction
+ 2. Maintenance
- 3. Engines
   + 3.1. Petrol engines (1,6 and 1,8 liters)
   + 3.2. Petrol 4-cylinder engine (2 liters)
   + 3.3. Petrol V6 engine (2,5 liters)
   - 3.4. Partition of engines (1,6 and 1,8 liters)
      3.4.1. Introduction
      3.4.2. Technical characteristics
      3.4.3. Repair work without engine dismantle from the car
      + 3.4.4. Major maintenance of the engine
      3.4.5. Engine checks
      3.4.6. Removal and engine installation
      3.4.7. Preparation for a partition
      3.4.8. Engine partition
      3.4.9. Partition and check of a head of cylinders
      3.4.10. Repair of valves
      3.4.11. Assembly of a head of cylinders
      3.4.12. Removal of pistons and rods
      3.4.13. Removal of a cranked shaft
      3.4.14. Check and cleaning of the block of cylinders
      3.4.15. Honingovaniye of cylinders
      3.4.16. Check of pistons and rods
      3.4.17. Check of a cranked shaft
      3.4.18. Check of radical bearings and bearings of rods
      3.4.19. Engine assembly order
      3.4.20. Installation of piston rings
      3.4.21. Installation of a cranked shaft
      3.4.22. Installation of a back epiploon of a cranked shaft
      3.4.23. Installation of pistons and rods
      3.4.24. Engine start-up after repair and a running in
   + 3.5. Partition of engines (2,0 and 2,5 liters of V6)
   + 3.6. Diesel engine of 2,0 liters
   + 3.7. Systems of electric equipment of the engine
+ 4. Heating and ventilation
+ 5. Fuel system
+ 6. Exhaust system
+ 7. Transmissions
+ 8. Coupling and semi-axes
+ 9. Brake system
+ 10. Running gear
+ 11. Body
+ 12. Electric equipment
+ 13. Electroschemes
+ 14. Good advice


3.4.5. Engine checks

GENERAL INFORMATION

Check by means of a vacuum measuring instrument
Connect a measuring instrument to an inlet collector. Warm up the engine and leave it to idle.

If the engine is serviceable, the measuring instrument should show 17–22 inches, and the arrow should twitch evenly.

If indications of a measuring instrument are lower necessary, the following reasons are probable: laying between an inlet collector and the carburetor or a throttle proceeds, the vacuum hose proceeds, the corner of an advancing of ignition or a camshaft angle of rotation is not adjusted.

If indications of a measuring instrument are lower normal on 8 inches – laying of an inlet collector proceeds or the injector is faulty.

If the arrow through equal intervals falls on 2 inches below a normal mark – valves proceed.

If the arrow strongly non-uniformly twitches down – jams the valve or spark plugs are faulty.

Arrow vibration on four inches and exhaust gases – directing plugs of valves are worn-out.

Fast vibration at increase in turns of the engine – proceeds laying of an inlet collector or a head, springs of valves are worn-out, valves are burned or candles are faulty.

Weak twitching of an arrow about a normal mark on 1 inch – problems with ignition.

Strong twitching of an arrow – laying of a head of cylinders is spoiled.

If the arrow slowly deviates on big pieces – fuel incorrectly mixes up, laying of an inlet collector or a throttle proceeds.

Increase turns to 2500 and muffle the engine, the arrow should fall almost to zero, then rise by 5 inches above a normal mark and come back to a normal mark.

If it does not occur, piston rings are worn-out.

If there is a long delay – the exhaust system is littered.

Compression check

PERFORMANCE ORDER
1. Disconnect ignition system, having disconnected a wire of a high voltage of system of ignition from a cover of the distributor of ignition, and having earthed it on the block of cylinders.
2. Connect the device for compression measurement to an opening of a spark plug of the N1 cylinder.
3. Completely open a butterfly valve and scroll a cranked shaft of the engine a starter. After one or two turns pressure of compression should will raise to the maximum mark, and then to be stabilized. Write down the received result.
4. Carry out similar check with other cylinders and write down the received indications.
5. Pressure in all cylinders should be identical. The difference more than in the 2nd bar between any two cylinders means malfunction. In the serviceable engine pressure should accrue quickly. The small pressure of the first step which is gradually raising at the subsequent steps, specifies that piston rings are worn-out. Small pressure of the first step which does not accrue at the subsequent steps, indicates leak in valves or on the punched laying of a head. Deposits on the lower parts of valves can as to become the reason of a low compression.
6. If at carrying out check you have doubts, address to skilled experts.
7. If pressure, in any cylinder too low, carry out the following check to establish the reason. Pour in a teaspoon of pure engine oil in the cylinder through an opening of a spark plug and repeat pressure check.
8. If after oil addition pressure of compression increased, it means that the piston or the cylinder is worn-out. If pressure did not increase, means, the reason in the worn-out or scorched valves or in the punched laying of a head of cylinders.
9. Low pressure in two next cylinders practically always means that between them head laying is punched.
10. If in one of cylinders pressure approximately for 20 % is lower, than in the others and the engine badly idles, it means that the reason, probably, the worn-out cam of a camshaft is.
11. If pressure too big, most likely, walls of chambers of combustion are covered with coal deposits.
12. After completion of check screw in spark plugs on places and connect ignition system.