How To Fix Rod Knock In Five Simple And Easy Steps

An engine rod knock results often due to low oil levels. The engine needs the oil in lubricating the cooling and moving parts in a car. With less or lack of oil inside your engine, excessive heat is most likely to occur also some parts will begin to wear out. These negative issues lead to a rod knock.

In case the car experiences a rod knock, most probably you will be forced to get the lower half of the motor replaced or the entire engine, which will depend on the extent of the damage.

This damage can result to affecting the rods, crank shaft and pistons. Replacing these particular parts can result in usage of lots of unplanned cash.

 Also, the vehicle will spend most of the time in the garage.However, to avoid these damages from causing savior loses, it is good you first familiarize yourself with the early signs of rod knock and how you will fix the problem.

Causes Of A Rod Knock

A rod knock occurs mostly when your rod bearing becomes wiped out. The bearing gets wiped out when your hydrodynamic oil wedge gets lost in between the connecting rod pin which is at the crankshaft and the bearing surface.

This process could be due to a combination or one of the following factors:

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    Low oil pressure
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    Insufficient oil viscosity
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    Minimal oil flow at the bearing surface
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    Excess oil temperature
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    High combustion pressures
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    High piston inertial forces; over revving the engine

All of the above factors can result in physical damage or overheat of the bearing material. In today’s engines, the bearing material consists of the lead-free aluminum alloy.

In case the bearing material overheats, it breaks and then melts away. When the material melts away, a large gap is left in between the crank pin and the bearing surface. When this happens, the crank pin will begin to knock the big end of your car’s rod which encloses it.

A bad rod knock can result in forcing one to walk home since the car cannot move. The big gap created between the crank pin and the bearing surface can result to a broken connecting rod as well as a subsequent hole at the sides of your engine block. The gap can as well lead to drop in the oil pressure and other cascading effects. 

Noises Which Are Often Mistaken For A Rod Knock

Here are some of the noises that might make you think that your car is experiencing a rod knock:

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    Piston Slap
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    Valve train ticking noises
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    Piston pin ticking
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What You Will Need When Fixing The Rod Knock

1. Mechanic’s Ramps

The mechanic ramp will help you lift the car from the ground level, and you will be in a position to easily access the engine.
You can also choose Jack Stands

2. Oil Pan

The oil pan will help you gather the oil that might spill from the engine parts.

3. Oil-Filter Wrench

The oil-filter wrench will assist you in removing the car’s oil filter and fitting the new filter.

4. A New Oil Filter

The new oil-filter will replace the old one since it might not be working well leading to the rod knock.

5. Fresh Oil

The fresh oil will be used to replace the drained oil.

6. Fuel-injection Cleaner

The fuel-injection cleaner will help in cleaning the grime that finds its way into the engine.

Step By Step Method Of Fixing A Rod Knock

 A rod knock is one of the common signs of distress in the inner parts  of the car. Some  of the causes of the rod knock need simple fixes;  however, some requires extra work. 

 However, this does not mean that the engine is beyond fixing. Before  calling an expert,  there are some steps you can engage in stopping the  knocking as well as be in a  position to stabilize the engine rod before  you decide to replace the engine completely.

Step One

 Drive the car on the set of the mechanic’s ramps. Ensure you set the  vehicle in a good  position for the not to slide back.

Step Two

 Place the oil pan under the oil cap. Then remove the oil cap which is  under the oil pan.  Completely drain the oil from the car. After all the oil  is removed, replace the oil cap.

Step Three

 Fit the oil-filter wrench in the middle of the oil filter to remove it.  Remove the oil filter by  turning the wrench clockwise. 

 Put the new filter in your slot then fit the oil-filter wrench around it to fix  it by rotating it  in an anticlockwise direction to tighten it.

Step Four

 Replace the drained oil with five quarts of fresh oil. Then get rid of the  oil pan and  inspect the rod bearings. 

 In case the bearings are loose, you will have to hear a knock coming  from the engine.  Replace or just tighten the bearings as required.

Step Five

 Pour the fuel-injection cleaner in the car’s gas tank to prevent grime  from getting its  way in the engine. Cleaning the fuel-injection system  helps in clearing out grime and  prevent the knocking.

 In case the car consists of a carburetor, there is no need of using the  fuel-injection  cleaner. Buy a carburetor cleaner which is sprayed  directly on the carburetor.


Fixing a rod knock is not hard when you decide to follow the above easy steps. Also, it is a good idea you familiarize yourself with the different causes of the rod knock so as you can prevent rod knock from occurring in the future. How to fix rod knock is easy when you follow the above five steps.

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