wilco golden larger no fermentation?

[trigger]

I am a bit rusty as regards home brewing, but purchased wilcos 40 pint golden lager kit which ive used in the past, followed instructions..
og was 1040 I added more sugar to bring it up too 1050 og, then added yeast, three days on I can see no sign of any bubbles through airlock.

tempreture is bang on at 21c I am not sure if there is a leak from lid/bung of f bin which I smeared with p jelly, or whether the addition of more sugar has killed the yeast.
I am unsure of what I can do next?

thank you

[Dads_Ale]

Take another gravity reading. This will tell you if it is fermenting. As you say there may be a leak that is bypassing the airlock.

[cwrw gwent]

The lack of bubbles is no indication that fermentation isn't occuring. Lids are rarely completely airtight so the excess CO2 may be escaping where the lid snaps onto the bin. In any case, there is no need to use an airlock when fermenting beer and a lid snapped about three quarters of the way around will hold in sufficient CO2 to protect the fermenting brew. If fermentation has started there should be a ring of yeast just above the fermenting liquid.

Use a hydrometer after a week to see if the gravity has dropped to c1010, give or take a point or two. If so, bottle if the gravity stays constant for three days.

[MartyMcFly]

Sometimes fermentation takes a few days to really see it working. Keep an eye on it in the next day or two and hopefully you'll see a krausen forming good n proper.

[cellone]

The only sign I get of fermentation is the smell but this is with lager yeast and not a lager style ale kit.

[trigger]

thanks all took a reading og was 1030, now its 1020 so I assume its fermenting, ive used exactly the same wilco kit a few times before and there was activity in the airlock, the lid of f bin is slightly bowed so some co2 must be forming, ill try my other f bin for next batch to see if what happens.

[cellone]

Knock the airlock on the head.