Just wanted to come in here and thank you personally for this solution. Bought my T300 about 4 months ago and been having issues for the past month. Finally got around to checking the Y tensioner and like the others in this thread, the cap in the front of the unit was broken. Your model got me back up and running. I’ve submitted a ticket to Sovol to get a replacement, but so far, crickets. To be fair, it is the weekend. If they do send a replacement, I’m probably going to apply your fix pre-emptively, although I think I’ll also look for a way to pin it into place to augment the superglue. Might even use some high strength epoxy. Anyway, thanks again, you saved my bacon.
You’re very welcome. Glad to hear it’s helping people the same as it helped me.