Belt tension and how to adjust it

I'm having a weird noise on my printer that I cannot figure what it is, it's like a clicking sound every time the extruder is running on the y axis, seems to be on the same spot always. 

I checked all the pulleys and tightened then - no change.

I loosened all the axis rods, moved the extruder, checked the blocks, all seemed to be normal - still making noises.

Lubed everything that should be lubed - still making noises. 

Now the only thing I have not changed is the belt tension, after loosening the rods one of the belts seems to be looser than the other ones. I don't think that's causing the noise, but want to make sure they are tightened to specs, so how do I do that? 

Could not find it anywhere. 

I have a similar issue. Mine clicking is coming from the rear left corner I think. Its annoying but seems to happen more the longer the printer is running. I think my noise is the rod bearing but they are greased and can't quite pin point the noise. 

It doesn't affect my prints so I am less worried and more frustrated. lol  I shutter to think of taking all the rods and bearings off to try and pinpoint the noise since the prints are great and out of fear it will never be put back together the same way. 

I guess if a bearing fails, then I will replace it at that time, but I really should pull it apart. Ugh!

Is that some kind of clicking sound? If yes, that would be bearing. Replacing it could be little bit painful but its possible. 

Right now I have not seen any reseller offering the bearings (almost other spares can be sourced tho).

Is that some kind of clicking sound? If yes, that would be bearing. Replacing it could be little bit painful but its possible. 

Yeah thats a pain in an of itself. lol Not really getting it out, which has its own challenges, but then sizing the bearing correctly and finding one to match perfectly. 

I always hate trying to size things. I use a micrometer but then if I don't hold the micrometer just right or it slips without seeing and even being off 1 mm means that for somethings there are a multitude of products available within the range of what it should be and what it shouldn't be. lol

Plus, they the bearings are screwed to the machine so I am guessing by the changeability, that the bearing is actually held by a metal brace/casing that is screwed to the machine or they are specially made bearings with the casing that screwed to machine.

Do you by chance know the size of bearings they are so we could order them and not have the machine apart waiting for delivery, just in case we might want to print something or in my case, too lazy to change them for a few weeks. lol

We can sell it as a service, bear in mind that its being sold as a package (8 bearings).

Marcin, I still don't know how to adjust the belt tension, is this information available somewhere? 

My "clicking sound" is intermittent not continuous, the printer only makes the sounds when printing on specific parts of the bed. It is most noticeable when printing the raft.

 Here's the link for the video