Vacuum Diffusion Pump Cleaning?

[CJay]

Be careful with MEK, I seem to remember it was banned because it was carcinogenic.

Used to be used to clean printing plates though so printer's supply houses may be able to supply an alternative.

[dexters_lab]

Be careful with MEK, I seem to remember it was banned because it was carcinogenic.

Used to be used to clean printing plates though so printer's supply houses may be able to supply an alternative.

you can buy it on ebay so it must be ok ;-) 

[calexanian]

MEK is fine. Everything is labeled as carcinogenic because of California. Anyways it looks like they were using good old octoil. It basically turns to tar eventually even if being very careful.  Over they years I have tried many things. The old official way to clean it was to fill them with really nasty acids. I mean truly horrid breathe it and die stuff, then turn the heater on and let it boil. For pumps that were going to see nothing other than silicone oil after that point I would soft media blast them to clean them. Now i just put them in a bucket of good old Berrymans Chem Dip. Available at wall mart. Its made specifically for removing oil sourced carbon deposits from engine parts. It comes in a bucket with a little dipper try just the right size for pump parts. It will not harm aluminum. Many a forged alluminum pistons have I cleaned with it.  Let the parts soak in that over night, then scrub them with a stainless steel brush and maybe let em soak again. Then rinse them, and I go over them with a rag and some brake cleaner. Its the safest easiest way. Swish the pump and parts in clean acetone when you are done. Acetone is the preferred solvent for any vacuum work. Oh, and one of those single end razor blade scrapers is good for breaking up the really thick tough spots.