INGERSOLL RAND Model 312 question

[Youngfd]

I have an IR Model 312 orbital sander that I have had for years, but maybe used a half dozen times. Last time I used it was probably 10 years ago. I tried to use it last week and it just shoots air out the exhaust holes when I push the lever down. I tried air tool oil and nothing. I even soaked it Marvel Mystery oil for a week and same results. Any ideas? Or where can I send it for repair?

 

[The Cobbler]

I'm wondering of the vanes are stuck in place or the bearings are seized a bit from sitting . I'd open it up at least to where I could spin the motor and see if that helps anything
maybe pull the valve assy out & see if there's any deteriorated o rings too

 

[American Locomotive]

If the air is coming out of the exhaust port, then it's most likely the vanes in the rotor are just stuck/gummed up. Pretty common on air motors that sit for a while. Usually if you give the air motor a little spin it will come good with some oil. Try "orbiting" the sand pad with the trigger depressed and air flowing through.