freeing pot metal parts

[John Hamilton]

A Madison-Kipp mechanical oiler has pot metal parts that work the pumps. Mine are frozen to the collars. Penetrating oils, carb cleaners, etc have not worked although they have soaked for about 9 months. Everything but the pot metal is shiny, bright and working. Help please.

[Jordan]

Have You Tried Gibbs John???

[Kevin O. Pulver]

John, I have limited experience with potmetal, but I believe that it can somewhat "expand" when it corrodes. I don't have a lot of confidence in pot metal stuff, but hopefully yours are OK. You might try the electrolysis. There is a lot of information archived here on that. Not sure how it works with potmetal. Maybe you will have to drill them out somehow and turn out some brass ones. I'm not at all familiar with the oiler pieces you mention so I don't know how tough that would be. I'm just concerned that after you get them out they might be worthless anyhow. Hope I'm wrong. Kevin

[Tanner Remillard]

Pot metal is so worthless it is REALLY hard to save if it is stuck or cracked. I would like to hear some good tricks too if there are any. Who ever invented that crap needs to be slaped in the face.

[Gasengin]

I used a small tip on my torch and lightly heated just the steel. Worked on mine, but the pot metal was in petty good shape. If the metal is cracked up, it might not be possible to get it apart without breaking it.

[KidDynamo]

Potmetals vary widely. Some will sweat beads of molten metal if heated with just a propane torch. I don't know for sure what these beads are- maybe lead or tin, but it is probably a bad thing for the part. Other potmetal alloys can take more heat but it is hard to tell ahead of damage-time.

If your assembly hasn't got seals and gaskets to worry about, I might consider using an oven or maybe a toaster oven to heat the entire assembly and then let it cool, numerous times. Just keep the heat down to a reasonably low temp, like 300 or 350 degrees or less, maybe working your way up the scale. The idea is that different metal alloys may expand and contract at different rates so heating and cooling cycles may create enough movement between them to allow some separation.

I am a big fan of hot water as well. If your assembly can withstand it, consider boiling it for a while in a pot of water. Sometimes water works when oil doesn't. Furthermore, if you get some water to "slip between the cracks" and then heat it in an oven, the steam produced can also cause some movement, even if potmetal swelling is part of the problem. However unlikely, though, beware of mini-steam explosions.

Along similar lines, several 'Stakers are strong promoters of "Simple Green" as a penetrant. Since oil-based penetrants don't seem to be helping you, maybe Simple Green might help. I bought a gallon of the stuff years ago, never figured out how to use it as a cleaner so I am now experimenting with it on old engine stuff.

I don't own a Madison Kipp lubricator and haven't seen the particular pieces that are troubling you so its a little unclear just what you are up against. The two Manzel lubricators that I own and have tinkered with don't seem to have parts that quite correspond to what you're facing. I think there is a bit of reprinted literature available as well as occassional pieces of original stuff on eBay.

Curious problem! Sounds like you've got the patience to solve it.

[Craig A]

I have found THIS method to work like a DREAM:
Gently heat the eccentric with a propane torch until water will bounce off when "flicked" on the heated part. At that point quench it. I haven't lost an eccentric yet with this method although I DID before I tried this method.
Then file the surface that rotates in the yoke so when it picks up moisture AGAIN it doesn't get stuck. They DON'T HAVE TO FIT that tightly to work properly.