Colder temperatures during the winter months often lead to cold cranking issues.
Cold cranking issues are commonly related to one of three factors:
- Oil viscosity.
- The condition of the starter main cables.
- The overall health of the battery.
Unfortunately, sometimes these factors are overlooked or ignored, particularly oil viscosity. We often just don’t think about it.
Factor 1 – Oil Viscosity
Switching to lower viscosity oil during the winter season offers benefits like:
- Easier engine start.
- Faster engine lubrication.
- Less energy consumption at engine start.
The lower viscosity oil will flow better at a lower temperature. When chilled to a temperature of 0 Celsius, 5W 30 will flow about 200% better than a more viscous 15W 40, and about 100% better than a 10W 40.
The flow of the oil has a direct impact on the amount of energy used to move the oil through the engine. This also directly impacts the cranking speed. A lower viscosity oil will facilitate a higher cranking speed, translating to quicker starts and lower starter current draws.
The selection of oil viscosity should, however, remain within the range outlined by the OEM’s guidelines.
Factor 2 – The State of the Starter Main Cables
Ideally, before the winter months, you check cables for loose connection sand corrosion. Both can increase circuit resistance and lead to slower cranking speeds.
A general rule of thumb:
- For every 1 volt drop in the starter circuit, there will be a loss of approximately 28rpm in cranking speed.
Factor 3 – Batteries
Healthy batteries are centrally important to reliable cold cranking.
Batteries with a low state of charge will not only cause a loss of cranking speed, but also a loss of available cranking time based on the diminished reserve capacity.
A decreasing battery charge affects cranking speed like:
- 100% charge, 83RPM
- 90% charge, 82RPM
- 80% charge, 80RPM
- 70% charge, 75RPM
- 60% charge, 62RPM
As you can see, cranking RPM drops off slowly at first, but dramatically as the charge drops below 80%.
When the time comes to upgrade your fleet with a new supply of alternators, starters, DC motors and solenoid switches, get in touch with a member of our team.
We ship fast and stock products from the most trusted manufacturers in the world.