Resealing Leaking Air Compressors

[Freshmeat]

I have two air compressors I coupled together for my garage. It's a great set-up, as I can close off either compressor when I'm simply tinkering or run both when we're doing heavy duty wrenching.

My problem is that both compressors have leaks so they run an awful lot more than they need to. Without running any tools, both kick on roughly every five to ten minutes.

The vertical unit is a 110v unknown brand (bought it on Craigslist for $50 needing a regulator) and the leak is at the pressure switch, where the plastic section mates to the metal. It appears there's a glue of some sort that was used to seal it somewhere along the way- I don't know if it's original adhesive or if it's a previous owner's failed attempt to seal it. The leak is on the top side of the switch directly between the metal and plastic.

The horizontal unit is an old Sears-Roebuck Craftsman compressor. 220v, oiled pump. Someone left it at my parents' house probably a decade ago and never went back for it after numerous reminders it was there. I replaced the switch and changed the oil; it works great other than the leak. This one is leaking at the round air manifold between the top and bottom sections (the flathead screws hold the two together) as if there's a torn gasket.

Does anyone know the best way to reseal these two compressors? They run great. The vertical is insanely loud (I believe part of the exhaust assembly is missing), but still works too well to really want to replace it.

I have clearance to go pick up a new Ingersoll-Rand compressor (220v, 60gal, 11CFM @ 90psi) but if I can get these two running for the cost of resealing them (or a new pressure switch for the upright) I'd much rather do that so I can spend the money on something more important, like a new tool box.

These are strictly for hobby work (primarily modifying off-road vehicles) so I don't specifically need a massive unit. The pair are almost perfect for most of what we do here, but I'd really like to get them sealed for longevity and so my electric bill can catch a break when they're being used.

 

[vga]

All threaded fittings need to be cleaned up with a wire brush and resealed by wrapping the male threaded pipe/ guage or pipe ****** with teflon tape the rescrewing said pipe/ guage back into its place and tightened using a small pipe wrench or channel locks. I would buy a new pressure switch, Plastic parts and HP air air a no no. Never mix the two yogether. Copper, or even 304 ss. Black iron will do in a pinch but will rust from the inside and can fail with out warning.

 

[Freshmeat]

All threaded fittings need to be cleaned up with a wire brush and resealed by wrapping the male threaded pipe/ guage or pipe ****** with teflon tape the rescrewing said pipe/ guage back into its place and tightened using a small pipe wrench or channel locks. I would buy a new pressure switch, Plastic parts and HP air air a no no. Never mix the two yogether. Copper, or even 304 ss. Black iron will do in a pinch but will rust from the inside and can fail with out warning.

Thanks for the input.

I've been through all the threaded fittings and cleaned them thoroughly before taping and reinstalling. They're not leaking any more.

The round manifold on the Sears unit appears to have had a gasket at some point. I'll try to pull it apart tonight to see for sure. I can cut a new one pretty easily.

On the pressure switch I was kinda leaning the same way to replace it. Adjoining plastic to metal requires adhesive and I just don't see it being a long term fix to basically just glue it back. I've read that the switch design on the vertical unit is pretty cheap, where the manifold is built into the switch. I'll get a new Square D switch and make a manifold for it this weekend. I'd rather spend a little extra now if it means increased reliability down the road.

Thanks again for the input. Any more tips while I have these apart would be appreciated.