Nozzle Leak and Print quality

Hello all, I’m hoping I can get some good advice here about a couple of issues I’ve been having with my figures/printer.

I’m using a TAZ 6 and everything was printing fine until…

Seemingly out of the blue the nozzle started leaking. I did my due diligence and searched google for any reasons/fixes for the issue and have since taken apart the extruder head, cleaned the throat and heat plate and put everything back together but the problem persists. After that I tried a few test prints and after dealing with the constant nozzle leak I’ve been noticing the head is having a hard time pushing filament through the nozzle (probably due to hardened filament from the leak) to create the border layer of the print and then after getting a constant flow one half of the print looks like garbage and the other half looks fine.

Anything else I can try or are there some calibrations I need to make?

I’ve only had these type of issues when my hot end fan started to fail and the filament was jamming in the hot end. Looking at your picture though, is there any possibility that the filament is sticking somewhere before it gets to the extruder. I’m thinking that might be the issue because the one half of your print looks perfect and the other half looks like the extruder is struggling.

In general, AO recommends not disassembling the hot end. They use high temp thread locker and specific torque specs when installing the nozzle, so if you don’t follow the exact same process, leaks could result. I had a similar leaking issue on my mini and eventually it stopped when the burnt filament clogged the leak. It prints fine now.

Long story short, check the hot end cooling fan.