Toyota Corolla

1992-1998 of release

Repair and operation of the car

Toyota Corolla
+ 1. Maintenance instruction
+ 2. Maintenance
- 3. Engines
   - 3.1. Petrol engines
      + 3.1.1. Repair work without dismantle of the engine from the car
      - 3.1.2. Dismantle and capital repairs Specifications Diagnostics of the engine by means of a vakuumer Check of a compression in engine cylinders
         + Dismantle of the power unit - methods and safety measures Alternatives of capital repairs of the engine Order of dismantling of the engine Head of the block of cylinders Repair of valves Conrod and piston group Dismantle of the crankshaft Block of cylinders Honningovaniye of cylinders Bent shaft Radical and conrod bearings Engine assembly order Piston rings Installation of a bent shaft and check of gaps of radical bearings Back epiploon Installation of conrod and piston group Launch of the engine after repair and a running in
   + 3.2. Diesel engine
   + 3.3. Engine electric equipment
+ 4. Cooling systems, heating
+ 5. Fuel, exhaust systems
+ 6. System of decrease in toxicity
+ 7. Transmissions
+ 8. Coupling and half shafts
+ 9. Brake system
+ 10. Suspension bracket and steering
+ 11. Body
+ 12. Electric equipment

bbeb4949 Conrod and piston group



Before removal of pistons assembled with rods remove a head of cylinders, the oil pallet and a tube of the index of level of oil (see subsection and subsection


1. Check a nail existence of the fillet formed as a result of wear of the cylinder from a piston ring (approximately in 6,0 mm from the upper edge of the cylinder). The fillet formed from a deposit or wear is removed development. Study the instruction of the manufacturer attached to the tool. If not to execute this operation, then at extraction of the piston with a rod from the cylinder breakage of the piston is possible.
2. After removal of a fillet turn the engine so that the crankshaft appeared above.
3. Before removal of rods check their axial side play by means of a set of probes. Lay the probe between a rod and the crankshaft, selecting thickness of probes achieve disappearance of a side play. The axial side play will be equal to the total thickness of probes at which the side play disappears. If the axial side play of a rod exceeds standard value, then the rod should be replaced.
4. Measure by just the same way an axial side play at other rods. If new rods are established (or the crankshaft), then the axial side play can be lower than norm (in this case it is necessary to proshlifovat rods, if necessary consult in a workshop of car service). Repeat the procedure for other rods.
5. Check existence of tags on rods and covers of rods. If tags are absent, then their nakernita so that the number of kerneniye corresponded to number of the cylinder in which this rod is established. The tags specified by an arrow belong to dimensional group of the conrod bearing, but not to serial number of a rod!.
6. Weaken an inhaling of nuts, turning off them on 1/2 turns at one time until nuts do not begin to turn away by hand. Uncover a rod of the first cylinder together with a connecting rod. Do not take a connecting rod from a cover.


In l engines 1,3 and 1,6 bolts of rods of a vpressovana in a rod body, and covers fasten nuts, in engines of 1,8 l of a cover fasten bolts which are rolled in a rod body.

7. Put on pieces of rubber or plastic hoses bolts of fastening of a cover of a rod not to injure a neck of a bent shaft and wall of cylinders at extraction of a rod.
8. Push out the piston assembled with a rod and the top insert of the conrod bearing through the top part of the cylinder. For this purpose use a wooden pro-rate, having rested it against the top connecting rod. If resistance to a piston exit is felt, then double-check completeness of removal of a fillet in the top part of the cylinder.
9. Repeat the procedure for all other cylinders.


At extraction of the piston with a rod from the cylinder turn the crankshaft so that to keep parallelism of a rod and walls of the cylinder. Do not try to take the piston when the corresponding neck of the crankshaft is under a big corner in relation to a cylinder axis.

10. After pistons with rods are removed from cylinders, again collect covers of rods with connecting rods, tighten nuts of covers by hand. Before assembly you store inserts on the place of their former installation that will exclude casual damages of internal surfaces of rods and conrod covers.
11. Do not remove pistons from rods (more detailed information is given below.


Before check rods and pistons it is necessary to clear and remove old rings from the piston.


Old piston rings when dismantling the engine are always subject to replacement.

1. Carefully remove rings from the piston, using special adaptation. At removal of rings do not damage the surface of pistons.
2. Scrape off a deposit from the bottoms of pistons. After removal of the top rough layer of a deposit clean the piston bottom a brush or an emery paper on a basis made of cloth. Do not clean off the deposit remains at all the wire brush got on the electric drill as it can lead to an erosion of soft alloy from which cast pistons.
3. By means of special adaptation remove a deposit from flutes of piston rings (a photo at the left). If such adaptation is absent, it is possible to use the old broken piston ring (a photo on the right). Delete only a deposit, being careful at the same time not to remove piston material. Try not to damage surfaces of flutes of rings.
4. After removal of a deposit carefully wash out surfaces of flutes of rings solvent, carefully dry compressed air (if is available). Be convinced of purity of drainage oil grooves in an installation site of an oil scraper ring, and also an oil opening in a rod.
5. If traces of considerable wear are absent and if boring of cylinders is not required, then pistons should not be changed. Normal wear is shown in the form of traces of uniform vertical development on the rubbing surface of the piston and in the form of small weakening of landing of the top compression ring. Nevertheless, replacement of piston rings at capital repairs of the engine is obligatory.
6. Carefully check existence of cracks on a piston skirt, on lugs of a piston finger and on airfields of piston rings.
7. Check existence of chips and zadir on the rubbing site of a surface of a skirt of the piston, traces of a progar in the central part of the bottom of the piston, and also a piston obgoraniye at the edges. If chips and teases are observed, then it indicates a frequent overheat of the engine, one of the reasons of which can be an abnormal combustion of fuel mix. In this case careful check of lubrication systems and cooling is required. The burn-out in the bottom of the piston demonstrates operation of the engine with the wrong installation of the moment of ignition. At the edges as a rule abnormal combustion (detonation) is the reason of an obgoraniye of the bottom of the piston. If the specified defects are found, then it is necessary to find their reason and to eliminate, otherwise repetition of abnormal wear is possible. An air suction on the soaking-up collector, the wrong installation of the moment of ignition, failure of the system of recirculation of exhaust gases can be the reasons of abnormal operation of the engine.
8. Corrosion of the piston in the form of not big poles (pitting) demonstrates penetration into the combustion chamber (and also in a crankshaft case) cooling liquid. Here again it is required to find their reason and to eliminate, otherwise corrosion will be shown on the repaired engine.
9. Measure a gap between the platform of a flute of a ring and a piston ring for what insert a new ring into a flute and lay the probe between a flute and a ring.
10. Check a gap in three-four places on length of all flute. Make sure that this ring corresponds to that flute in which will be established as rings have different thickness. If the gap exceeds the set limit, then the piston should be replaced.
11. Check a gap between the piston and the cylinder, having measured diameter of the cylinder (see subsection and diameter of the piston. Make sure that measurements are carried out on couple of interfaced details. Measure diameter of the piston on a skirt, in the direction perpendicular axes of a piston finger.
12. The size of a gap is defined as a difference of diameters of the cylinder and a skirt of the piston. If the gap exceeds the set limit, then the block of cylinders is subject to boring, and pistons and rings should be replaced repair.
13. Check a gap between a piston finger and a head of a rod for what it is necessary to shake the piston and a rod in opposite directions. The notable side play will indicate the raised gap and need of repair of this connection.
14. If it is necessary to remove pistons from rods for replacement of pistons, or for elimination of a side play of a piston finger, then it is necessary to hand over them in a workshop of car service. At the same time it will be necessary to check a bend and twisting of rods, later it will be necessary to replace pistons.
15. Check existence on rods of cracks and other damages. Uncover at this stage of conrod bearings, get bearings, wipe the landing surfaces of bearings on a cover of a rod and on a rod, and check existence of cracks, scratches and zadir. After check collect a rod, having installed into place the bearings which were in operation, and tighten nuts by hand.


If strong knocks in rods were the reason of repair of the engine, then surely replace rods.