Connecting rods

The connecting rod converts the sliding movement of the piston into a rotating movement. The distribution, a crankshaft pulley and, in many cases, a vibration damper is attached at the front of the crankshaft. At the rear of the crankshaft, the flywheel and clutch are attached to transmit the forces to the gearbox.

The crankshaft is a carefully designed component which is critical in terms of fit and balance. If the fit or balance in the crankshaft is not correct, this results in major damage due to the high rotational speeds the crankshaft achieves in the combustion engine. The crankshaft rotates in sliding bearings in order to ensure the lowest possible resistance. It is important that the radial play, i.e. the clearance between the crankshaft and the main bearings, is optimal. If the clearance is too small, no oil film can form between the crankshaft and the slide bearings, resulting in extra wear/heat in the bearings. If there is too much clearance, too little oil pressure builds up and excessive wear and tear also occurs, often accompanied by abnormal noises in the engine block, especially with a warm engine (thin oil).

Wilmink Engine Parts has the right crankshaft, connecting rod or accessories for your vehicle. In addition, you will also find items such as a clutch kit, flywheel and torque converter for an automatic transmission. If you have any questions or would like advice, please contact our product specialists. They will be happy to assist you.

Balancer shaft
The balancer shaft is used to make combustion engines run (virtually) vibration-free. Engines with a small number of cylinders, such as 3 or 4, naturally produce a relatively high amount of vibration compared to, for example, a 6 or 8-cylinder engine. This is because each power stroke in an engine with fewer cylinders has a relatively large interval compared to an engine with a greater number of cylinders. To counteract these vibrations, manufacturers use balance shafts. The balance shaft is driven by the distribution and should therefore always be 'on time' when work is done on the distribution.

Clutch pressure plate
The clutch pressure plate clamps the clutch release plate to the flywheel so that a mechanical connection can be made between the engine and the gearbox. By means of the clutch pedal, the clutch pressure plate is controlled so that clutch engagement or disengagement between the engine and the gearbox can take place at the desired moment. A defective clutch pressure plate can be recognized by broken pressure fingers or diaphragm springs. The clutch pressure plate must then be replaced in its entirety; repair of individual parts/springs is not possible. When the clutch pressure plate is replaced, it is advisable to also replace the clutch release bearing and the clutch release plate. This is because a lot of labour is involved in this operation and the relatively low cost of the clutch release plate and clutch release bearing are not significant compared to the total operation.

Clutch release bearing
The clutch release bearing is mounted on the inside of the gearbox and slides along the input shaft to operate the clutch. By means of a 'fork' the thrust bearing can apply pressure to the diaphragm springs of the pressure group and thus operate the clutch. A defective clutch release bearing can often be recognised by an abnormal noise when decoupling. This is because the clutch release bearing is then loaded and makes more noise when it is worn out. In addition, the clutch release bearing can wear on the guide sleeve, making it heavier than normal to operate the clutch pedal.

Clutch disc
The clutch takes care of the connection between the engine and the gearbox, which eventually causes the engine’s power to go to the wheels. The clutch release plate, or clutch disc, is mostly made of organic friction material to grip in a smooth and comfortable way, which is desirable for cars on the street. In racing applications, Kevlar and carbon friction materials are also used, as these clutches have to endure more than regular cars.

One symptom of a worn clutch is a slipping clutch, where the speed of the engine increases without the car accelerating proportionally. A high-gripping clutch or a heavy-gripping clutch are also symptoms of a worn clutch. In some cases the gearbox can also shift gears with difficulty. Usually the clutch, if handled properly, will last about 150,000 - 200,000 km.

When replacing the clutch disc, it is also recommended to replace the clutch pressure plate and clutch release bearing, as they are often worn out at the same time. When a new clutch disc is mounted on an old clutch pressure plate, the clutch disc may slip because the clutch pressure plate has too little clamping ability due to age.

Clutch kit
Here you will find the complete clutch kit for your car. The clutch kit usually consists of the following parts: clutch disc, clutch pressure plate, (hydraulic) clutch release bearing. Some clutch kits are also extended with a (dual-mass) flywheel, new flywheel bolts and a top bearing. If you wish to order individual parts for the clutch, you will find this in the other categories. Naturally, our product specialists will be happy to assist you.

Torque converter
The torque converter is used in an automatic transmission and transmits power from the engine to the gearbox. The torque converter consists of a pump wheel, stator and turbine wheel. There is oil in the torque converter and this is used for the transmission of power. When the pump wheel is revved up by the engine, the oil is thrown out against the blades and the turbine wheel (and thus the gearbox) is powered. Unlike a manual gearbox, there is no mechanical clutching and there is always a deviation in the speed of the pump wheel and of the turbine wheel. This also results in the drive losses of a torque converter. Slightly more modern automatic gearboxes also have a so-called lock-up which ensures that in top gear there is a mechanical connection and therefore fewer drive losses.

Crankshaft
The forces exerted on the pistons are transferred to the crankshaft by means of the connecting rods. The crankshaft converts the sliding movement of the piston into a rotating movement. The distribution, a crankshaft pulley and, in many cases, a vibration damper is attached at the front of the crankshaft. At the rear of the crankshaft, the flywheel and clutch are attached to transmit the forces to the gearbox.

The crankshaft is a carefully designed component which is critical in terms of fit and balance. If the fit or balance in the crankshaft is not correct, this results in major damage due to the high rotational speeds the crankshaft achieves in the combustion engine. The crankshaft rotates in sliding bearings in order to ensure the lowest possible resistance. It is important that the radial play, i.e. the clearance between the crankshaft and the main bearings, is optimal. If the clearance is too small, no oil film can form between the crankshaft and the slide bearings, resulting in extra wear/heat in the bearings. If there is too much clearance, too little oil pressure builds up and excessive wear and tear also occurs, often accompanied by abnormal noises in the engine block, especially with a warm engine (thin oil).

Make sure you choose the right bearings when installing a new crankshaft or a reground crankshaft. The clearances should always be measured before everything is closed.

Flywheel
The flywheel is mounted at the rear of the crankshaft and ensures that the engine runs more evenly. Essentially, the flywheel absorbs energy from the engine and stores it. A heavy flywheel is difficult to get started but is also harder to slow down. Because of the flywheel, the engine will 'shock' less at the moment of ignition. On the outside of the flywheel, where the toothing is located, the starter is attached in order to be able to start the combustion engine. Furthermore, the flywheel transfers the driving forces to the gearbox via the clutch, which in turn transfers them to the wheels.

Nowadays a dual-mass flywheel, also called two-mass flywheel, is often mounted. This is actually two flywheels on top of each other with a spring-loaded component in between. The function of the spring-loaded intermediate component is to absorb even more vibration and abnormal noises compared to a 'normal' single-mass flywheel. When the clutch is engaged, the plates can separately rotate a little on the spring-loaded component. This makes the care more comfortable and reduces the vibration and abrupt forces going towards the power train.

A dual-mass flywheel is subject to wear, as opposed to a single-mass flywheel. The two plates must not twist too much in relation to each other, because then the vibrations can be amplified instead of dampened. Which clearance is still within tolerance is specified by the manufacturer. When the gearbox is disassembled, this clearance can be measured by twisting the part on which the clutch engages.

Guide bearing
The guide bearing or pilot bearing is mounted in the flywheel of the engine. The guide bearing centres the end of the input shaft. When the guide bearing is worn out, the grinding dust it has created can end up in the clutch at an advanced stage of wear. In addition, a worn guide bearing can result in damage to the gearbox.

When replacing the flywheel (and clutch + clutch pressure plate) it is advisable to always preventively replace the guide bearing too. This part is relatively inexpensive and easy to replace when already performing the above mentioned work and potentially prevents an annoying future repair.

Various individual parts:

Crankshaft sealing plug
Main shaft gear
Clutch parts
Crankshaft plug
Crankshaft key
Flywheel repair kit (trucks/industry)