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How to Remove a Crankshaft From Under the Car

by John Stevens J.D.

An engine's crankshaft operates to transfer the power produced by the engine through the transmission and drivetrain. Tremendous force is generated through the crankshaft, and over time the bearings that allow the crankshaft to turn freely can wear out. In addition, at the back of the crankshaft lies an oil seal. If this oil seal becomes corroded, an oil leak will result. In either event, the only way to repair the problem is to remove the crankshaft. Although crankshafts are traditionally removed after the engine has been pulled from the engine bay, it is possible to remove the crankshaft without pulling the engine.

Remove the engine's belts. The engine's belts are used to power the engines accessories, such as the power steering, alternator and air conditioning. To remove the belts, locate the adjustment bracket for each accessory. The adjustment bracket is used to attach the particular accessory to the engine. Loosening the bolts which hold the adjustment brackets into place will release the tension on the accessory's belt. Once each belt has been loosened, pull the belt away from the pulley which attaches to the harmonic balancer.

Remove the pulley which attaches to the harmonic balancer. The pulley is secured to the balancer with three bolts. Remove each bolt with a wrench and pull the pulley away from the balancer.

Remove the harmonic balancer. Use a wrench to remove the single bolt from the center of the harmonic balancer. This bolt is used to connect the balancer to the snout of the crankshaft. Attach a harmonic balancer remover, to the face of the balancer with the supplied bolts. Turn the threaded rod located in the center of the puller in a clockwise direction. As the threaded rod is turned, it will gradually pull the harmonic balancer off of the crankshaft.

Drain the radiator by removing the radiator's drain plug. The drain plug is located on the bottom of the radiator. Use a wrench to turn the drain plug in a counterclockwise direction to remove it.

Remove the water pump. The water pump is located on the front of the engine, and is secured to the engine with several bolts of varying size. Remove the rubber hoses which attach to the water pump by first turning the screw on each hose clamp in a clockwise direction with a flathead screwdriver, then by pulling each hose away from the water pump. Remove each of the water pump's bolts, then pull the water pump away from the engine to remove it.

Remove the timing chain cover. The timing chain cover sits directly behind the water pump, and is attached to the engine with several bolts. Remove the bolts with a wrench, then pull the cover away from the engine to remove it.

Remove the timing chain. The timing chain consists of two sprockets and a single chain. The larger sprocket fits over the end of the camshaft, and is secured into place with three bolts. Remove the bolts with a wrench, then pull both sprockets away from the engine to remove the timing chain.

Remove the oil pan. The oil pan is attached to the bottom of the engine with several bolts, which surround the circumference of the pan. Remove the bolts, then pull the pan away to expose the oil pump and the crankshaft.

Remove the oil pump. The oil pump is located either at the front of the engine or at the rear of the engine, depending on the particular engine. The oil pump is usually held into place with two bolts. Remove the bolts and pull the oil pump away from the engine.

Remove the connecting rod caps. The connecting rod caps attach to the crankshaft, and transfer the power produced in the combustion chambers to the crankshaft. There is one connecting rod for each cylinder. For example, if the engine has six cylinders, six connecting rod caps will have to be removed. Each connecting rod cap is held into place with two nuts. Remove each nut, then pull each connecting rod cap away from the crankshaft.

Remove the main caps. The main caps are used to secure the crankshaft to the engine block. There are generally a total of four main caps. Most engines use two bolts to secure each main cap into place, although some engines use four bolts per cap. Remove each cap to allow the crankshaft to drop away from the engine. Take care when removing the final cap, as the crankshaft is very heavy.

Warning

  • To avoid injury, hold the crankshaft against the engine when the final cap is removed, then slowly lower the crankshaft out of the engine to complete the removal process.

Items you will need

About the Author

John Stevens has been a writer for various websites since 2008. He holds an Associate of Science in administration of justice from Riverside Community College, a Bachelor of Arts in criminal justice from California State University, San Bernardino, and a Juris Doctor from Whittier Law School. Stevens is a lawyer and licensed real-estate broker.

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