Got a Hobart 250 amp Beta Mig from Craigs list for 100 bucks. Owner had two, and didn't know why this one stopped working. Got it home and it turns out it was just a broken wire on one of the control relays. Now it seems to work fine, but the tap selector switch is very stiff to turn, so I opened it up. The switch contacts look fine, but the inside is coated with some type of grease which has gotten very stiff. I guess the grease helped lube the switch to prevent corrosion and keep it free moving. I've cleaned out the old grease and am thinking of using Silicone spark plug contact grease or some thick Dow Silicone "O" ring lube that I have. I'm hoping the wiping action of the contacts will clear the contacts enough to allow good contact. The old grease dissolved in solvent very quickly, so it don't think the original grease was silicone based. The contacts are 1/8" thick by
3/4" wide bare copper strips in a housing about 6" diameter. Anyone try this on switch contacts for low voltage? The Silicone is a bitch to remove if this does not work..Thanks