IPU’s inertia starters are a tried and tested method in the world of engine starting. They are the perfect choice for starting engines in non-hazardous areas and are widely used on pumps, compressors, winches, industrial vehicles and gen-sets.

IPU’s inertia starter motors are available for air (pneumatic) and hydraulic forms

How inertia starters work

Inertia starters work by rotating a pinion and moving it forward through centrifugal force towards the ring-gear. As it continues to spin, the teeth of the pinion lock into the ring-gear and crank the engine.

A key advantage of inertia starters is that they automatically disengage once the engine has started. This prevents the starter from over-speeding which could be damaging and costly.

The advantages of inertia starters

Inertia starters have several features that make them more suitable than pre-engaged starters for some applications:

• Size: inertia starters benefit from being smaller than pre-engaged equivalents; they are well-suited to smaller engines and engine bays where space is a major consideration.
• Remote relay option: to reduce the space envelope even more, if starter orientation isn’t an option, a remote relay valve can be used rather than the starter’s integrated relay valve.
• Power: inertia starters boast a better weight-torque ratio than other types of starter motor. They are lighter than other starter motors with a similar cranking torque capacity.
• Simplicity: IPU’s inertia starters have been developed as an easy-to-install, fit-and-forget system, saving you costs on both installation and maintenance.
• Rugged: the rugged cast-iron construction of our inertia starters makes them ideal for difficult and challenging environments. Depending on the model they are certified for temperatures between -30°c and +80°c and are approved for use in salt water environments.
• Safety: IPU’s inertia starters can be fitted with beryllium-copper pinions to reduce the spark risk when the starter engages with the engine’s ring-gear.

Types of inertia starter

IPU offer three ranges of inertia starter: air (pneumatic), hydraulic and spring:

• Air (pneumatic) starters can be used to start engines up to 150 litres. They offer the convenience of connecting to the existing pressurised air supply in a building or on a vehicle or vessel. IPU’s air starters are sold under the Jetstream brand.
• Hydraulic starters can be used to start engines up to 80 litres. They are used extensively in shipping and on offshore platforms where hydraulic systems are already in place.
• PSpring starters are well-suited to smaller engines up to 18 litres. Their main advantage is their total independence and simplicity. They require no external energy source (the energy is stored in a spring that is wound manually) and are the most reliable form of engine starting.

Choosing between different inertia starters

IPU offer a wide range of inertia starters and fitting options. The simplest way to select between them is to call one of our engineers for advice. They will be able to guide you towards the ideal system for your application.
Before speaking to us it would be useful to have as much of the following information as possible to hand:

• Engine make and model
• Flywheel details (number of teeth, pitch, etc.)
• Mounting details (space for starter’s ‘nose’, starter orientation, etc.)
• Performance (number of consecutive start attempts, length of start attempts, recharge time, etc.)
• Application (offshore marine, barge, oil & gas, vehicle, explosive atmosphere, etc.)
• Number of engine cranks in a specified time

You can download IPU’s Enquiry Questionnaire to record this information.