I rebuilt mine, just used hot water to clean the crusties off, reassembled gutenteit.
Mine soon got new crusties around the sight glass and elsewhere, so maybe I should have done something better about gaskets. Don’t remember but I think I just cleaned up and re-used the originals, not smart. Buy a rebuild kit from Gasflux Co.
Alistair Spence, who was briefly a full-time pro before Match went out of business in y2k, turned amateur hobbyist. He rebuilt his and documented it on Flickr.
No telling how long his overhaul would have lasted, because his entire shop burnt up in the horrible fire that wiped out Paradise CA.
I think it was Eva @LiberationFab that mentioned good results from her rebuild, no crusties yet after some amount of time, so I guess that means it can work and stay clean with the proper gaskets, and maybe assembly technique? Eva please correct me if that wasn’t you.
EDIT: ah yes, here is Eva’s rebuild experience: https://forum.customframeforum.com/t/gasfluxer-setup-tips/864