What To Do When Your Inverter Generator Won't Start

How to Clean the Carburettor Jets on Your Inverter Generator 

One of the most common, but costly mistakes that we see made with portable generators / suitcase generators occurs when users store their inverter generators for long periods of time and forget to remove the previously added petrol from the generator.

This often occurs over the winter but problems can occur in as little as two weeks and can cause starting problems next time the inverter generator is used. 

The unleaded petrol that is used by most inverter generators has changed and does not last as long as it once did.

If petrol is left in the generator's carburettor, over time it starts to go waxy, deteriorate and lose the combustion properties that help start the generator. 

There is a relatively simple fix if that involves draining the float bowl and cleaning the carburettor. 


Sometimes, the problem is solved by draining the old petrol that has been left in the carburettor float bowl. 

In order to do this, remove the 10mm head bolt that sits at the bottom of the float bowl pointing towards you at an angle (not the one at the bottom, which is the float bowl locating bolt). Note - some machines may have a flat screw head. 

The petrol that sits in the float bowl should now flow out. 

Replace the drain bolt and prime the carburettor with about 30 to 40 pumps of the primer bulb (or pull start the recoil starter around 20 times depending on the inverter generator) to refill the float bowl.

Try to start your generator again. 

If this still has not resolved the problem then you will need to clean the carburettor. 


Cleaning the carburettor takes a few minutes and could save you the cost of sending the generator back to the seller or manufacturer.

Once you have removed the side access panel, proceed with the following steps: 

  • Remove the float bowl retaining bolt. Ensure that this is the bolt in the centre of the bowl and not confused with the drain bolt which is offset. 
  • Remove the float bowl.
  • Remove the float pivot pin and float.
  • Unscrew the main jet and remove the inverter's emulsion tube.
  • Use an airline to blow the main jet and emulsion tube. Make sure to also blow out the hole from which these were removed and the hole that the float valve was seated in. 
  • Reassemble in reverse order from above. 

If this looks too complicated or you don't want to do it yourself, there are two things you can do to prevent stale petrol causing problems: 

1. Make sure you drain the engine of all fuel when you finish using it. If you are leaving the machine over the winter, we recommended that you empty both the fuel tank and the carburettor. 

2. Use a fuel stabiliser which can give fuel a longer life, often between 1-2 years. 

If you have any further questions, contact a member of our team on 01437 700123 or by emailing sales@thepowersite.co.uk.