I have a petrol hedge trimmer and the rubber grommet that the fuel pipe feeds through into the tank has developed a leak. The tank is polypropylene.

I'm thinking of using something like a Hermatite sealer, but it has to be fuel proof and go off so it doesn't end up gumming up, smearing and sticking to everywhere. I haven't used anything like this in about a gerzillion years though.

Does anyone with considerably more knowledge on this sort of issue have any advice?

I had one on my car, I used rubber sealant a bit if inner tube and a jubilee clip. But if it’s a very thin pipe this might not work.