Toilet weak flush

[novicey]

Hi all,
I need your help.
Recently my toilet hasn't been flushing with full power, appears less water coming out into the toilet bowl than normal & takes a couple of flushes to get rid of a No.2.
Tried a plunger to see if anything blocked but nothing came out. Read somewhere that water level in the tank needs to be adjusted, problem is I don't know how to do that. Would be grateful if anyone could advise how to do it by looking at the attached picture.
Thanks.

 

[Newboy]

Water level is fine - it's more likely to be a perished diaphragm in the siphon.

The siphon is the red topped item in the centre of your photo - come back if you need help changing it. A couple of pictures of the siphon taken from the front and a photo of the cistern and WC bowl would help if you need more assistance.

 

[Madrab]

Personally I'd adjust your fill valve as the water level looks too high, you want it on the fill level line marked on the back of the cistern. Where the arm of the ball lever meet the valve, the threaded black plastic bolt turns clockwise a couple of turns, you may have to loosen the plastic nut on the left of the bolt until the fill is right.

+1 re the syphon, time for a new one.

 

[Nige F]

Chuck the syphon and replace with a flap valve - kits from any DIY shed

 

[novicey]

Thanks for the replies. Going to tackle the siphon I think. Will post more pictures if I struggle!

 

[dilalio]

Not flushing a nr.2!

Reminds me of the time an old colleague of mine was asked by a customer why his toilet was constantly getting blocked...

Nige replied "well sir, the problem is that you have a 4" soil pipe and a 6" ar$€hole!" - I kid you not, that's what he said. I nearly fell down the stairs laughing