Spare Parts


We can supply you with a wide range of spare parts for your machinery such as; engines, filters, hydraulic spares and other additional parts.

ECU – 

ECU, or Engine Control Unit, is the system which manages the operation of the engine – and maximises power whilst minimising fuel consumption. ECU’s also handle the sensors and let you know if there are any faults or damage with the engine. As these units are a computer, they are delicate and can be damaged by either physical ingress of water or dust, or electrical reasons suchspare parts as voltage spikes.
When an ECU is damaged, generally the entire engine will cease to function, and the ECU needs to be replaced to get the machine up and running again. Your options here are to buy from your local main dealer, or from an overseas stockist of genuine parts. As ECU’s are highly specific for the particular machine you are working on, there are no aftermarket suppliers who can reliably build replacement ECU’s. Feel free to contact us, we are happy to advise on your options on this.

Slew Rings – 

Slew rings were developed for hydraulic excavators and cranes, where it is necessary for the machine body to rotate on the base chassis. Slew rings are a large diameter ring with teeth on the inside rim, which engage with the slew motor. The slew motor is a hydraulic motor which rotates the upper.
As the slew ring is put under high stress loads, and is constantly in use, the teeth can wear and shear, resulting in a malfunctioning part. In this case you may have to look at replacing the slew ring. Reconditioned slew rings can provide you with a very good quality product at a low price, and enable you to get up and running quickly. If you are looking at used, non-refurbished units, you should pick one from a machine with low overall hours, where the slew ring will still have plenty of life left in it. New genuine CAT slew rings can be sourced from your local CAT dealer, whilst aftermarket units are available from many suppliers.
Sigma are glad to help advise you on your options on this, and help you with the best solution to your issue.


Submit your Enquiry For Parts Here


Injector – 

Injectors are very delicate items, and well-performing fuel injectors are critical to good engine performance. Poor fuel quality can damage injectors, especially when fuel is impure or contaminated with water, soot, dust or algae. In the case where diesel injectors are worn, this will show in blue smoke from the exhaust on the machine. Diesel injectors on Caterpillar excavators moved from manual to electronic systems on the “C” series. Sigma have experience in getting injectors rebuilt, which is often the cheapest way to repair the engine.


spares parts


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