I have been asked this a few times You have to put a spanner to hold where is the thread (there is a shaved off part to Grip) then grab the end with a pair of grips and twist anti clockwise when back to you, its stiff so as often they used loctite to lock it. Dont loose the little magnet there here is some photos to explain
I often get asked about these door and if they can be swapped etc the answer is no The 144 has a bigger door, the 244 246 have a different catch Lad called Tom sent me this photo TASCAM 244 door on top, 246 door on bottom. Note how large 244 hinges are and latch on opposite side. 246 door about 3mm wider.
I had an MSR-24 in to break but my lad managed to break the rear bus in taking them off, but i have just had a customer with same problem, it seems these bushes suffer from the same fatigue as the TSR-8 ones in that they warp a little and its impossible to get them off As a solution you can use the A3440 ones and cut them down at the back they are a perfect fit
I am writing this more for my information and its a bit of a work in progress here. Teac used a few motors over the years mostly i cannot see any difference just in some of the bigger machines they seem a bit meatier as draw more current but not that much, I was not sure if they can be swapped around as I do not have the manuals here. There seems to be 3 different Pcbs at least from what I can see and I am unsure of the pinouts so I have listed them here, some use...
I have seen lots of machines with a missing/broken button They are very easy to replace Get the front panel off and take of the whole pcb 5 llittle screws then you can get out the push button bank. There is a rod at the back with a very tiny almost you would miss it circlip in the middle, get that off an rod slides out, add the new button in and slide it back re- insert the clip and put all back together Here are some photos to help Before After job done