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Hi, quite recently I saw a plunger

Hi, quite recently I saw a plunger

Hi, quite recently I saw a plunger

Hi, quite recently I saw a plunger type positive displacement pump which had a strange plug at the bottom of the casing. The plig seemed to be slighlty leaking while running. When I removed the plug l, I found that it is not a plug but a sintered bronze air filter. This air filter was on the hydraulic oil side of the casing.
My question is that since we do not have a spare air filter, can I plug this with a temporary plug (not filter) and run the pump Also what is the purpose of this air filter, at the bottom of the pump casing. Thanks

RE: Hi, quite recently I saw a plunger

We have machines that use a sintered bronze plug as a breather vent. But, I cannot imagine using one of these at the bottom of a housing with liquid in it. Your description makes it sound like this plug is submerged with liquid on the inside of the housing. That could not be right. If it is a breather that is designed to allow a vapor space in the hydraulic system to breath, then plugging it up could cause problems. Oil doesn't like to run smoothly down a drain if it cannot breathe. That is why the drains in your house always have a vent pipe passing up through the roof. We would really need to seed cross-section of your machine, calling out the location of the breather plug to evaluate the possible implications of plugging the hole.

Johnny Pellin

RE: Hi, quite recently I saw a plunger

Many equipment casings, such as gear boxes have plugs on each side to allow it to be mounted in various orientations. They should all have solid plugs except the one on top is for a breather plug.

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