Check the LED carefully, its probably another YLOD mate. Sometimes the fix didnt remelt the solder properly, and after a few hours use, and sudden cooling when you shut down it cracks again overnight.
Try fixing it again, but check the following:-
1. The thermal paste must not be too thick.
2. Make sure the two clamps holding the fan in place are secured. Bend these clamps to give them some extra tightness.
Also, do you have a fat old PS3, or a newer slim one? If you have the newer slim model, before even opening it, do a fan test. Even with a YLOD it will put the fan through all cycles, and even eject any disc. If this test fail on the slim, your power supply need replacing. For a Fat there is no way but opening and trail and error.
A few things from my own tests on the YLO

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1. Position - I tried the standing up and down position. Standing up I get around 2 to 3 months, lying flat a month. Make sense since heat rises.
2. I had the PS3 close to a speaker, and i can confirm the vibrations with the heat buildup also influence the time between repairs. I am now on month 4 after moving the speaker to the ground since the last fix. I had this before, like this, the first time it lasted 3.5 months, the other 5, this time still going. Close to the speaker, 2 to 3 months max.
Let me know how this work out for you mate. But overall, with every YLOD the PS3 is nearing its end

I have one dead for a year now, even after every single component was microsoldered. So the lad further up wasnt trolling