The only problem is a full CLA on a Prontor shutter on these cameras is far more than it's worth. I pisked up a mint Prontor-S (post WWII) for £2 ($3.20) the other day it's never been used on a camera, another with a brand new Novar for £7 and a third with a Kershaw lens for about £10.
So I'd say go for a self clean initially it's revived many shutters for me all of which still work perfectly some quite a few years later :D I tend to use a few drop of Isopropyl alcohol initially into the shutter mechanism them fire it off to free it up. This often does the trick and it's rarer I do a full flush clean.
You made a good find with that NIB shutter!
There will always be tinkerers. It's only human to want to test and explore possibilities. Some people dont have the financial means to send a $50 camera out for a $150 cla. So people should not worry too much about stressing DIY or professional cleaning to others. Lots of people are very talented with mechanics naturally, even if their main job is not in that field. I am also sure many professionals in camera repair have trashed just as many cameras too.
I would stress that people go ahead with each option intelligently. Weigh the importances of each choice and ultimate consequences of it. If you do choose DIY find as much information like online guides, service manuals, and repair books. The right tools for the job go a long way. Photograph your steps if particularly complex. And most importantly take your time and think!
With many of the older folding cameras it's worth looking for dud/broken cameras with scratched or foggy lenses etc for parts before emabrking on expensive CLA's. I struck lucky buying 6 shutters recently and solved many of my repair or missing shutter problems plus getting a 203mm f7.7 Ektar and two Novars in the deal. (The Ektar was worth 3x what I paid for the lot).
I can't speak for the US but most repairs or CLA's here have a minimum £50 charge in the UK that means it's often unecomomic when you can pick up a similar camera in fully working condition for less.
You need to take into account the condition of the camera and it's value when restored both in monetary terms and usability and that's really what I'd guess Brian and I mean by it's worth.
... and yet I could have done a overhaul myself had time not been an issue, saving $135 and staying well within the financial worth metric!
p.s. Shutter overhauls in US vary in price: about $60 if you are willing to wait an indeterminate amount of time, $85 (+ shipping) if you want to send it to Mr. X who has quite a following, and $135 for the guy in my neighborhood who has "1000 years" of experience and a great reputation.
another p.s. It seems to me that the cost of shutter overhauls versus the dollar value of the lens/shutter is what rightfully drives many people to D-I-Y solutions. I know that is how/why I made a transition from repairing clocks to shutters too. I am a prime example taht a passionate ametuer can indeed repair shutters without too many casualties if one takes a studious approach.
Worth has nothing to do with this thread.
I'm sure all the guys with a 1000 years experiance got their feet wet just like this.. a $10 junker, flea market find or in a green moldy old box in the attic.
It is so much fun to get that first one working no matter how you do it. Pour a can of lighter fluid on it, take it appart or just spit in the works, if it goes, you've been bit for life.
I hope the OP will post some results before this thread gets way too long to read.
If you intend on servicing your own shutters in the future then experimenting on $10 clunkers is certainly worth your time for the experience. I know for a fact, though, that simply spraying or dunking in lighter fluid isn't good enough. Not in the long-run anyway. Also, it's imperative to remove the cells to avoid exposure of the lenses to the cleaners... if for no other reason than to avoid having to clean it off of them.
Naphtha or white gas work fine but you need to work the shutters all all speeds while they're still wet. This may take some time... many workings. Lastly, leaving shutter mechanisms clean and "dry" is not good enough. As others stated, the moving parts need lubrication with ultra-light oil... just "tiny" amounts in the right places.
I'm no expert on ANY shutter. I just use my eyes and ears... and do my best. I've never had a problem.