Troubleshooting - a procedure for expert evaluation and determination of the cause of engine failure or any other mechanism. It consists in the identification and elimination of defects, accompanied by an assessment of their value, confirmed by the relevant act. Troubleshooting is most often carried out for cars that have been in an accident.
Features of the troubleshooting procedure
Troubleshooting - an assessment and diagnostic procedure that identifies hidden damage. It is carried out by a specialist through inspection using electronic and technical means.
During troubleshooting, internal damage to the mechanism, the operability of individual systems are detected and the need to replace functional parts is determined. Based on the results of the check, a list of services, used parts and calculation of the full cost of work and components is created.
How much is engine troubleshooting? The price varies from 300 to 1500 rubles, depending on the need to parse the vehicle.
The information given in the sample act of troubleshooting can be used for:
- purpose of insurance payments;
- confirmation of costs incurred for repairs;
- maintenance support or warranty.
Troubleshooting is carried out within one day in the presence of the customer. On the day of the appeal, a sample act of troubleshooting is filled out and written and oral recommendations are issued.
Statement
Identified malfunctions in the operation of the mechanisms or the unit are made out of the inspection list, which indicates the amount of work and their calculation. The specialist draws up a statement and indicates in it:
- Types of defined and completed work.
- Scope of activities.
- The list of used materials and their cost with the obligatory indication of exclusive.
The work specified in the inspection list must be properly executed:
- The list is detailed.
- The type of work performed is being clarified.
Properly prepared estimates facilitate the preparation of a service agreement and save time on both sides. Important components of the document are the cost of used parts and materials and the calculation of work.
Car troubleshooting
In the event of an accident, the following actions are performed to assess damage and apply for insurance compensation:
- Call the traffic police, issuing a certificate and a description of visible damage to the vehicle.
- Drawing up the appropriate application for the insurance company.
- Drawing up an appeal to a car expert. The specialist assesses the condition of the vehicle using modern electronic equipment and fixes it in documents indicating the required costs and ways to eliminate internal and external defects: straightening, welding, painting, replacement of spare parts.
- The car service master must provide the vehicle owner with an inspection certificate of the vehicle with a description of the price list and a list of fixed defects. Based on the received document, the car owner orders a troubleshooting process.
Powertrain troubleshooting
Engine troubleshooting is carried out in several stages:
- Troubleshooting is carried out simultaneously with the process of disassembling the power unit. A car service specialist evaluates the condition of each part and draws certain conclusions based on a preliminary visual assessment.
- After determining the degree of wear, all parts are sorted into groups. The components to be replaced are added to one, the parts without significant damage, suitable for restoration, are added to the other.
- Components suitable for repair are carefully measured. The obtained parameters and dimensions are compared with the nominal. In most auto repair shops, craftsmen draw up a inspection sheet that lists the restored parts and parts that were not used during the repair. If the next repair is necessary, such a document simplifies engine troubleshooting.
Cylinder Block Troubleshooting
The central part of any engine is the cylinder block. Failure of it can lead to serious technical problems. Timely and competent troubleshooting of engine parts will help determine the causes of motor failure and the possibility of its further operation.
- Troubleshooting involves inspection of the cylinder block. The specialist conducts a visual inspection to identify deformations, cracks in vulnerable points.
- Block testing is carried out when antifreeze gets into engine oil or oil into antifreeze in order to find cracks in the cooling and oil channels.
- The integrity of the temperature and oil plugs is checked.
- Special tools measure cylinders. This allows you to assess the level of their production and determine further performance.
- Blocks with replaceable sleeves are checked in places of a landing belt of sleeves.
If the unit has the listed damage, the specialist decides whether it is advisable to repair certain parts. After repair, the unit is washed from oil traces and other contaminants. All work must be carried out in accordance with technical procedures.
Cylinder Block Defects: Deep Scuffing
Reasons for the appearance:
- Overheating of the engine, leading to the destruction of the pistons.
- Foreign objects getting into the engine cylinders.
- Violation of the fixation of the piston pin in the piston bosses or the weakening of its landing in the connecting rod head.
The troubleshooting process includes replacing pistons and connecting rods, checking the cooling system. The cylinder block is repaired by a liner.
Cylinder surface scratches
Causes:
- Failure of piston rings.
- Engine overheating.
- Piston jumper defects between grooves.
- Operation of the motor with a damaged air filter for a long time.
The correct installation of the ignition system is checked and its adjustment is carried out. Diagnostic experts advise using fuel with an octane rating recommended by the manufacturer. If necessary, sharpening the dimensions of the piston rings or sleeve.
Cylinder surface development
Causes:
- Malfunction of the ignition system.
- Failure of the power system.
Diagnostics, repair and adjustment of the power system and the ignition system are carried out. Strong wear on the surface of the blocks is repaired by a sleeve or a bore.
The absence of a hone mesh on the surface of the cylinders is one of the indirect signs of wear. During troubleshooting, specialists check the taper, output and ellipse of the cylinders as follows: each cylinder is checked by an indicator caliper at three points in two mutually perpendicular planes. In the stopping zone of the upper compression ring, the most severe wear is usually observed. Methods of boring and honing followed by sleeve application are used when working out in cylinders of more than 0.1 mm.
Cracks in the cylinders
Reasons for the appearance:
- Damage to the connecting rod and piston as a result of ingress of third-party objects or water hammer into the cylinder.
- Engine overheating.
When diagnosing cracks during engine troubleshooting, the cylinder block is decommissioned, but not repaired. It is extremely rare to cylinder the cylinder. The specialist diagnoses the cooling system, intake and exhaust tracts. The presence of cracks in the cylinder block and their dimensions are determined by crimping. Damaged parts are replaced with new ones.
Cracks in the area of the holes for the head bolts and on the upper plane of the block
Causes:
- Motor overheating.
- Incorrectly tightened cylinder head bolts.
- Poor flushing and purging of the unit before assembly, which leads to dirt or liquid in the thread for bolts.
The cylinder block must be replaced. Extremely rarely, cracks are welded, after which the block is processed mechanically.
Defects of other surfaces of the cylinder block
Causes:
- Piston deformation.
- The cliff of the connecting rod.
- Deformation of the engine compartment as a result of an accident.
- Overheating of the power unit.
- Incorrectly tightened cylinder head bolts.
The cylinder block is completely replaced. With minor defects, welding of cracks and machining of the cylinder head are possible.
Thread warp in mounting holes
The main reason is the incorrect tightening of the cylinder head bolts. It is eliminated by drilling holes and threading a new diameter. Installation of futorok is provided.
Significant wear on rollers and main bearings
Diagnosed seats under the camshaft bushings, auxiliary shafts and main bearings . Most often, this procedure is carried out for engines of construction equipment and heavy freight vehicles. The seats of the main supports and their covers are thoroughly cleaned and returned to their places, their bolts are tightened with a torque wrench. An indicator caliper, adjusted to the required size, checks each support in several planes. The difference between the measured and nominal dimensions should not exceed 0.02 mm.
In a similar way, the seats of various bushings are checked. Their repair consists in the installation of new bushings of increased diameter.
Based on the diagnostics and troubleshooting of the engine, the suitability of the cylinder block for further operation and the possibility of repair work are determined. After repair, the cylinder block is rinsed and purged with compressed air to remove contaminants.
To summarize
It is only possible to evaluate the actual condition of the engine after troubleshooting the engine valves. Based on the results, a preliminary estimate is made, that is, the cost of a major overhaul or engine overhaul is determined.
Before buying a contract unit, it is advisable to carry out troubleshooting and disassemble the engine. As a rule, this allows you to get accurate information about the degree of wear, the severity of the deformation and the possibility of repair work.
Car service specialists are able to restore aluminum cylinder blocks, provided that the manufacturer does not provide for the possibility of repairing such BCs. Simply put, such blocks are not repairable, and the factory technology is not suitable for overhaul, respectively, there are no official factory solutions for repairing engines with aluminum cylinder blocks.
In such cases, the craftsmen resort to the sleeve of aluminum blocks. Correctly performed repairs in most cases increase the working life of the engine, which after a major overhaul will last at least 100 thousand kilometers.
Overhaul and engine troubleshooting on expensive cars with factory technology not provided for this are the most optimal and reliable solutions, in contrast to the acquisition and installation of a contracted used power unit. The technical condition of the used motor is reliably unknown, so its installation entails certain risks.