Yashica T3 light leak

Sometimes there is, sometimes there isn't. When there is, it is always in the same place of the frame (and same shape). I inspected carefully the inside - no damages or deterioration of light seals, all very clean... So - what could be the reason?
Below are two photos taken in the sequence - one shows the leak, another is without.

Is there something in the mirror box causing a reflection? Remove the lens, set the shutter to "T" or "B" so the mirror is up, see if some black paint is missing somewhere.

Could be the film pressure plate too. I'd ck that carefully as well.

momus said:

Could be the film pressure plate too. I'd ck that carefully as well.

Click to expand...

Right, based on the location of the leak it must be it... Thanks!