Vintage Sears Compressor

[elise111]

Picked up an oldie and have been going through it. After thinking about what I want to do with it, I settled on the goal to have 'free air' available to cyclists in the neighborhood. I've read through some threads here and wanted to run a few questions by the experienced folks.

Background- this is the '1/2hp' version but has been fitted with a 1hp 3450 rpm sears motor.

1. Motor pulley is 1.75in and looks small compared to the similar vintage compressors I've seen posted here. All of those seem to be the larger versions of this compressor though. Does anyone know what size this should be?

2. The notched V belt (11AV1080) is old and chewed up, and perhaps the small pulley doesn't help belt life. Assuming the pulley is the wrong size, does anyone know the belt size to go with it?

3. I added some foam as an air filter. I noticed that one side of the foam blows upwards. Does this mean a reed valve leak perhaps?

4. Oiling the sleeve bearing motor- do I remove these rubber plugs and fill the vertical cavity with SAE 20?

Pete
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[Showkey]

Those were infamous for rusting tank bottoms. Pin hole leaks.......so be careful.

That is likely 30-40 years old.

 

[elise111]

Thanks- is it safe to assume that leaks just mean it won’t hold air, and it may send rust through the lines? Or is there a safety risk as well?

 

[American Locomotive]

Usually it just manifests itself as a leak, but there is a chance the tank could rupture. I'd just take a hammer and tap all long the bottom of the tank listening for soft spots.

It's hard to tell for sure, but I would say that pulley size *seems* about right for a 1/2HP compressor with a 3450 RPM motor and a twin-piston pump.

If you have air blowing out of one of the filters, the read valve is likely in a bit of distress. Sometimes just running the compressor for a while will get them to come back. If not you may need to very carefully try and clean the valve. Likely some dirt stuck in it if the compressor ran with no filter for a long time.