Does the voltage drop at cranking affect the lift kit?
At cranking the battery terminal voltage falls briefly; on a sound battery this value should typically not go below 10.5 V, and above 11 V is considered good. Values falling to 8-9 V and below point to a battery, cable, ground or starter motor problem. With drops this deep, 12V lift kits should not be used while cranking; the kit should only be operated after the engine has started.
To measure the voltage drop, connect the multimeter to the battery posts and watch the lowest value while cranking. Assessment:
- 11 V and above: The battery and starter circuit are in good condition.
- 10.5-11 V: Borderline; the battery may have aged, clean the chassis and terminal connections.
- Below 10.5 V, especially 8-9 V: The battery, heavy cables, chassis connection or starter motor should be examined.
In practice, follow these rules:
- Do not press the kit switch at the same moment you press the starter.
- Do not use the kit repeatedly while the engine is not running; the LFT20 draws 10A on average and tires the battery quickly.
- With a weak battery the mechanism moves slowly; this is not a kit fault but a supply problem. First check the battery and chassis connections.
An unhealthy charging or battery system is the most common cause of misdiagnosis.
The full topic: Converting a tractor hydraulic lever to electronic control