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FAQ / Frequently Asked Questions – Starter Motor
How do I know if the starter motor is the problem and not the battery?
If the machine clicks but doesn’t start, or starts slowly even though lights and electronics work normally, the starter motor is often the cause. If everything dies during the start attempt, it usually indicates a weak or discharged battery. It’s always a good idea to begin by measuring the battery and checking cables and grounding points.
Can I use a starter motor with higher kW than the original?
Yes, in most cases this works fine – a more powerful starter motor can even improve starting performance, especially in cold weather or on large diesel engines. The important thing is that the mechanical fitment and electrical values (voltage, rotation direction, gear) are correct.
How do I find the correct starter motor for my machine?
The easiest way is to search using the OEM number from your existing starter motor. You can also search by machine model, engine version or manufacturer reference. At Olsson Parts, you can additionally filter by voltage, kW and fitment.
What symptoms indicate that the starter motor needs replacing?
Common signs include clicking sounds, sluggish starting, slipping gears, uneven operation or overheating. If the battery is fully charged and cables are properly connected, these symptoms often point to a failing starter motor.
What is the difference between a standard starter motor and a gear-reduction (planetary) starter motor?
A gear-reduction starter motor is more compact, more efficient and requires less current while delivering high starting power. It is common in construction machinery and machines with high load demands. Standard starter motors are simpler in design and often cheaper, but work well where loads are lower.
How many teeth should my starter motor gear have?
The number of teeth varies between engines and is a critical part of compatibility. Choosing the wrong number of teeth can prevent the starter motor from engaging the flywheel correctly. Always compare with your existing starter motor or verify the specification using the OEM number.
Can I replace the starter motor myself?
Yes, on many machines it is possible to replace it yourself. Remember to always:
- Disconnect the battery before starting the work
- Document the cable connections
- Check grounding points during reinstallation
If access is limited or if you are unsure, professional assistance is recommended.
How long does a starter motor last?
Lifespan varies depending on usage, machine type and maintenance. A starter motor used in harsh environments or together with a weak battery will wear out faster. With a healthy electrical system, good wiring and regular checks, a starter motor can function for many years.
What affects the price of a starter motor?
The price is influenced by:
- Power output (kW)
- Type of motor (standard or gear-reduction)
- Manufacturer
- Fitment and machine requirements
A more expensive starter motor can offer greater reliability, especially for machines used professionally or in extreme conditions.
Do I need to replace the solenoid at the same time?
Many starter motor problems are caused by worn solenoids. If the starter motor is older, it may be wise to replace the entire unit. Some solenoids are available separately, but if the starter motor shows additional signs of wear, a complete replacement is recommended.