Overhaul engines 2.0 and 2.5 l Mazda 626 (5)
This section covers engine overhaul operations, including cylinder head and cylinder block parts. The chapter includes both recommendations regarding both the organization and preparation of engine overhaul work, the purchase of spare parts, and a detailed description of the procedures for dismantling and installing engine parts, as well as methods for checking the technical condition of parts.
The following sections assume that repairs are carried out after the power unit has been removed from the vehicle. Repair operations without dismantling the power unit from the vehicle, as well as the dismantling and installation of all attachments of the engine, necessary for the overhaul, are described here and here.
The above technical data is only needed to check the technical condition of the parts in the repair procedures described below.
Technical characteristics of 4-cylinder engines
Cylinder diameter 82 mm Piston stroke 90 mm Volume 2.0 liters Compression pressure in cylinders: - nominal 171 psi - minimum 119 psi Maximum permissible pressure...
Cylinder diameter 82 mm Piston stroke 90 mm Volume 2.0 liters Compression pressure in cylinders: - nominal 171 psi - minimum 119 psi Maximum permissible pressure...
Technical characteristics of 6-cylinder engines
Cylinder diameter 83 mm Piston stroke 73 mm Volume 2.5 liters Compression pressure in the cylinder at 250 rpm: - nominal 203 psi - minimum 142 psi Oil pressure (the...
Cylinder diameter 83 mm Piston stroke 73 mm Volume 2.5 liters Compression pressure in the cylinder at 250 rpm: - nominal 203 psi - minimum 142 psi Oil pressure (the...
Repair work without removing the engine from the car
Many basic repairs can be performed without removing the engine from the vehicle. Before starting any work, it is highly advisable to flush the engine compartment and...
Many basic repairs can be performed without removing the engine from the vehicle. Before starting any work, it is highly advisable to flush the engine compartment and...
General notes on engine overhaul
It is not always easy to come to a conclusion about the advisability of an engine overhaul, since it is necessary to rely on a number of indicators. High mileage is not...
It is not always easy to come to a conclusion about the advisability of an engine overhaul, since it is necessary to rely on a number of indicators. High mileage is not...
Alternatives to engine overhaul
When carrying out major repairs yourself, various options are possible. The decision to replace the cylinder block, connecting rod-piston group and crankshaft depends on...
When carrying out major repairs yourself, various options are possible. The decision to replace the cylinder block, connecting rod-piston group and crankshaft depends on...
Engine disassembly sequence
The easiest way to disassemble the engine and perform all types of work is on a portable stand. Before mounting the engine on the stand, it is necessary to remove the...
The easiest way to disassemble the engine and perform all types of work is on a portable stand. Before mounting the engine on the stand, it is necessary to remove the...
Checking with a vacuum gauge
Vacuum gauge Typical vacuum gauge readings 1. Low constant pressure 2. Low fluctuating pressure 3. Regular pressure surges 4. Random pressure surges 5. Rapid vibration...
Vacuum gauge Typical vacuum gauge readings 1. Low constant pressure 2. Low fluctuating pressure 3. Regular pressure surges 4. Random pressure surges 5. Rapid vibration...
Checking the compression in the cylinders
Disable the ignition system by disconnecting the ignition high tension wire from the distributor cap and grounding it to the cylinder block. Connect a compression tester...
Disable the ignition system by disconnecting the ignition high tension wire from the distributor cap and grounding it to the cylinder block. Connect a compression tester...
Engine dismantling methods
If a decision has been made to dismantle the engine for major repairs or repairs of major components, then certain preparatory measures must be carried out. It is...
If a decision has been made to dismantle the engine for major repairs or repairs of major components, then certain preparatory measures must be carried out. It is...
Removal and installation the engine
If you are removing the engine for the first time, you need to prepare a room for this, preferably equipped with a lift. You will need an assistant, ideally someone with...
If you are removing the engine for the first time, you need to prepare a room for this, preferably equipped with a lift. You will need an assistant, ideally someone with...
Overhaul and inspection of the cylinder head
Caution! Reassembling and inspecting the cylinder head requires special tools and parts that you may not have. Therefore, if you are an amateur, it will be much more...
Caution! Reassembling and inspecting the cylinder head requires special tools and parts that you may not have. Therefore, if you are an amateur, it will be much more...
Cylinder head assembly
1. Lubricate the valve guides and stems with engine oil and insert the valves into the cylinder head. 2. Lubricate the piston rod seals with oil and install them in...
1. Lubricate the valve guides and stems with engine oil and insert the valves into the cylinder head. 2. Lubricate the piston rod seals with oil and install them in...
Removal pistons and connecting rods
1. On 4-cylinder engines, remove the engine reinforcement section (see subsection 3.2.14 ). 2. Using a special tool, remove the ledge at the top of the cylinder caused...
1. On 4-cylinder engines, remove the engine reinforcement section (see subsection 3.2.14 ). 2. Using a special tool, remove the ledge at the top of the cylinder caused...
Removal the crankshaft
Sequence of unscrewing the bolts of the cover block (6-cylinder engines) 1. Before removing the crankshaft, measure its free play using a special device or a feeler...
Sequence of unscrewing the bolts of the cover block (6-cylinder engines) 1. Before removing the crankshaft, measure its free play using a special device or a feeler...
Checking the cylinder block
1. Turn the plugs in the holes by hitting the side of each plug with a blunt rod. 2. Remove the plastic plugs from the block. 3. Using a plastic scraper, scrape away all...
1. Turn the plugs in the holes by hitting the side of each plug with a blunt rod. 2. Remove the plastic plugs from the block. 3. Using a plastic scraper, scrape away all...
Cylinder honing
This procedure requires special tools and skills, so it is best to contact a specialist. After honing, a pattern of cross lines intersecting at an angle of approximately...
This procedure requires special tools and skills, so it is best to contact a specialist. After honing, a pattern of cross lines intersecting at an angle of approximately...
Checking pistons and connecting rods
1. Remove the piston rings using a piston ring installer, being careful not to scratch the piston. 2. Using a wire brush or fine sandpaper, clean the piston crown of any...
1. Remove the piston rings using a piston ring installer, being careful not to scratch the piston. 2. Using a wire brush or fine sandpaper, clean the piston crown of any...
Checking the crankshaft
1. Clean the crankshaft with solvent and dry it with compressed air. 2. Inspect the crankshaft bearings for wear, scratches, corrosion or cracks. 3. Remove burrs around...
1. Clean the crankshaft with solvent and dry it with compressed air. 2. Inspect the crankshaft bearings for wear, scratches, corrosion or cracks. 3. Remove burrs around...
Checking and selecting main and connecting rod bearings
Causes of bearing wear 1. Reduction of the tensile strength of the metal; jagged scratches 2. Incorrectly planted; bright (polished) stripes 3. Scratched with dirt; dirt...
Causes of bearing wear 1. Reduction of the tensile strength of the metal; jagged scratches 2. Incorrectly planted; bright (polished) stripes 3. Scratched with dirt; dirt...
Checking camshafts and tappets
Camshafts 1. To measure camshaft runout, please contact a specialist. 2. Inspect the shaft bearing journals for scratches and wear marks. If the shafts are worn, replace...
Camshafts 1. To measure camshaft runout, please contact a specialist. 2. Inspect the shaft bearing journals for scratches and wear marks. If the shafts are worn, replace...
Installing piston rings
1. Before installation, it is necessary to check the end and side clearances of the piston rings. 2. Install the upper compression ring into the cylinder using the...
1. Before installation, it is necessary to check the end and side clearances of the piston rings. 2. Install the upper compression ring into the cylinder using the...
Installing the crankshaft
Main Bearing Cap Bolt Tightening Sequence (4-cylinder engines) Main Bearing Cap Bolt Tightening Sequence (6-cylinder engines) Checking the lubrication clearance of the...
Main Bearing Cap Bolt Tightening Sequence (4-cylinder engines) Main Bearing Cap Bolt Tightening Sequence (6-cylinder engines) Checking the lubrication clearance of the...
Installing pistons and connecting rods
Location of bearing end clearances 1. Front of the engine 2. Upper part of the piston A. Upper compression ring clearance B. Second compression ring clearance C....
Location of bearing end clearances 1. Front of the engine 2. Upper part of the piston A. Upper compression ring clearance B. Second compression ring clearance C....
This section is available on: russian, bulgarian, belarusian, ukrainian, serbian, croatian, romanian, polish, slovak, hungarian
More sections on repairs of other Mazda models
• Power unit: Engine repair (gasoline) Mazda3 BK (2003-2009)
• Power unit: Engine repair Mazda6 GG (2002-2008)
• Power unit: Engine repair (gasoline) Mazda3 BK (2003-2009)
• Power unit: Engine repair Mazda6 GG (2002-2008)
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- General information
- Introduction to guide
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- Troubleshooting
- Maintenance
- Power unit
- 4-cylinder engines
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- Engine overhaul
- Cooling and ventilation
- Power and exhaust systems
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- Automatic gearbox
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- 2.5 petrol engines
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- Diesel engine 2.0
- Engine electrics
- Cooling system
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- Control system
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- Steering
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