Why could your generator fail to start?

All machinery is liable to failure at some point, so remaining vigilant and maintaining regular servicing is critical to ensuring resilience. Like any piece of equipment, a generator isn’t always 100% reliable.

We’ve outlined some common reasons why your generator might fail to start, along with our suggestions to reduce the risk of failure:

Battery failure

One of the most common reasons a generator will not start is due to a battery failure. This is often caused by a loose connection or a sulfation build-up. When sulfate molecules in the battery acid (electrolyte) become discharged, it causes a build-up covering the plate which means the battery is not able to provide enough current. It’s also recommended that connections should be regularly cleaned and tightened. 

Failure can also occur due to the charger breaker being inoperable which is usually caused by a fault within the battery charger unit. This can happen after routine service or maintenance when the charger has been turned off and not turned back on again.

We recommend battery replacement every three years. 

Low coolant levels 

Coolant levels should be checked on a regular basis by visually checking if there are any puddles of coolant. The coolant colour varies but it most commonly will look red. 

When the generator is operating under load, the thermostats open completely when the engine reaches the optimum operating temperature, which means the radiator cannot allow the correct flow through the core. When the engine cools off and the thermostat closes, the level drops and activates a low coolant level shutdown to your generator.

 We suggest you test your generator with an external load bank with sufficient load to reach the temperature value needed to open the thermostats. 

Bad fuel mix

 A bad fuel mix can happen for several different reasons:

• If your fuel runs out the engine will take in air but no fuel
• The air intake can become blocked so there is fuel but no air
• The fuel system might be supplying too much or too little fuel to the mix so as a result, combustion in the engine does not occur properly
• There could be impurities in the fuel, such as water in the fuel tanks, and this causes the fuel not to burn 

Controls not in auto 

When your control panel displays the “not in auto” message, this is a result of human error, normally due to the main control switch being left in the off/reset position. If this is the case, the generator may not start in the event of a power outage.

To help prevent any of the issues mentioned in this article, you must ensure your generator is regularly maintained – a proactive servicing programme is the best solution for keeping on top of any issues before they arise. 

If you need help, don’t hesitate to contact service@dtgen.co.uk