The coils still look OK.
This is a bit costly, but should work.
Find a ceramic heat sink NOT metal, that can be glued to the coil, big enough to do it some good, small enough to fit under the chassis, use thermal conductive epoxy to stick it together, making sure the epoxy touches both the coil and heat sink.
Once cured, it should run cooler.
https://www.amazon.com/MG-Chemicals-...Q%3D%3D&sr=8-3
example
https://www.walmart.com/ip/Whigetiy-...erId=101180981