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Is your tractor engine knocking?

Is your tractor engine knocking?

Tractor’s engines are known for being loud. They make all types of noises due to the heavy workload they take on and their complexity. However, there’s one noise that stands out, and that’s a steady knocking.


If there’s a rhythmic clunking sound coming from your tractor’s engine it’s likely that there’s something amiss. Diagnosing the problem isn’t easy but there are common causes and solutions that arise frequently. To help you locate and remedy the problem quickly, we have outlined the most common engine faults and their respective symptoms below.


Faulty injectors


Injectors are central components of tractor engines. In fact, so central that with the slightest mishap, the whole engine tends to fail – loudly. The injectors carry fuel into the engine, where it combusts under high-pressure in the cylinders. This combustion provides the energy for piston movement, which in turn essentially “works” the engine.


 The miss-timing of the combustion process between the injector firing and piston movement is what causes the knocking. If this goes smoothly, the energy is channeled into tractor function, if not, it becomes noise. A leaky or loose injector can not only damage the cylinders/pistons but can have adverse knock-on effects on the whole tractor. When diagnosing your tractor’s knocking sound, an overheated or unusually cold engine while running suggests injector problems.


Bearing failure


Bearings need the proper tolerance in order for the engine to operate at its peek best. The bearings receive lubrication from your oil pump and with the proper tolerance keeps your oil pressure at the right pressure for your tractor’s engine optimal performance.If aligned correctly, they allow greater freedom of movement to other vital engine parts. As you can guess, if they fall into disrepair or slip out of place, a lot can go wrong. The first warning sign could be a knocking sound. The most common cause is the bearings around the crankshaft becoming loose. This allows it to hit off other (or vice versa) parts of the engine. Particularly the bottom and top of the piston stroke, meaning that the faster the tractor drives, the faster the knocks will become.


Low oil pressure - premature engine failure


If your tractor’s oil pressure is dropping to below normal it may be caused by a worn out oil pump. Another possibility is the bearings on the connecting rods and or the main crank bearings, either ones can cause low oil pressure and cause engine knocking. This issue will lead to a catastrophic engine failure.


Worn valves train


Blue smoke, cylinder head knocking, high oil consumption, and misfiring are just some of the downsides to shabby valve trains. Wear and tear can add up on valve trains over time if a tractor is not regularly maintained. One notable cause is allowing the engine to overheat often or letting the oil run too low. However, valve train issues can still arise over time, even with proper care.


Antifreeze in the oil


It’s not as farfetched as you think that some antifreeze might creep into your engine’s oil. It’s a regular cause of coolant levels dropping due to a cracked engine head or head gasket failure and or sealing rings around the cylinder liners. All of these can lead to a drop in antifreeze levels and will cause engine problems.


 When oil and antifreeze mix, a viscous, somewhat gloopy brown or white solution is formed. This unfortunate transformation robs the oil of its lubricant abilities and causes oil to deteriorate. Consequently, parts of the engine that require lubrication are left dry and at risk of damage. Most of the time, when antifreeze is at fault, there might not be any sounds other than your temperature gauge is higher and antifreeze levels have dropped. The best way to stay ahead of this failure is to always check the levels of your fluids before starting the tractor. When performing your own oil change and you see either green or red antifreeze come out at first, it is a sign of a failure happening.


Diagnosing the core problem behind engine knocking or overheating and remedying it as soon as possible is the surest way of avoiding further damage. This damage can often be costly to repair and may require the replacement of certain engine parts. So, the faster the problem is fixed, the better.


However before making any big financial decisions, It's worth getting an inspection done on your tractor by a specialist.

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