My 3 carb bodies are now immersed in jugs of cellulose thinners for a week
There has been some previous discussion over the confusion between Lacquer thinner and Cellulose thinner. If your "cellulose" thinner has been used similarly in the past then obviously it's OK.
Some time ago someone posted photos of carb bodies that had been left too long in a cleaner or solvent; I'm not positive but Cellulose thinner is jumping out at me. The carbs were ruined do to a chemical reaction that badly oxidized and coated all surfaces. The throttle shaft seals would likely have been compromised, as well.
"Test" for an adverse reaction on a float bowl first, if soaking carbs in an unproven cleaner or solvent:
Those were my carbs Scotch. I quoted Cellulose Thinners but that's probably just what we are used to calling Lacquer Thinner in the UK. My carbs had a white powdery deposit all over them when I took them out and I was horrified by this but it did all just wash off with a little effort. It may have be due to the pre-treatment of boiling them in lemon juice (I'm not sure this helped at all!) -
Once the lemon juice and thinners treatments were over I cleaned them with your tool set
My Carb Bodies have been "bathing" in cellulose thinners for a week now and do have patches of white deposits as expected, here and there when removed, but they all go immediately once washed in petrol after to make them very, very clean.
Throttle shafts are all perfectly ok, but given a squirt of WD 40 for good measure.
I can also see WD40 go in and come out of every internal channel when used with the Red Straw, so everything clear, especially the collection of 3 very small holes in the upper venturi. It comes out of there like a shower now after the thinners bath, which proves further this process removes ALL internal crap and any blockages.
Done this many times on many sets of carbs and it works 100% well.