Air bubbles in return line

[F-Type]

Hi

I noticed when the car was idling while doing some break-in the other day, that there were air bubbles coming from the engine/carburettor end of the fuel return line.

Is this normal? Doesn't feel like air should be entering the system anywhere there.

 

[WoodiE]

@F-Type sounds like you've either got a leak in the fuel tube or possibly tank.

 

[F-Type]

Or carburettor?

When priming, I get quite a lot of bubbles, but I think I've seen that on other two stroke engines as well, like the weed-cutter etc. so I didn't think too much about that, but was pussled when I saw it during normal operation. Should there be none also when priming?