Old Air Compressor Road Testing??

[dimwittedmoose51]

Have found an old(1946, supposedly) PAR(Lynch Manufacturing Co., maybe out of Ohio?) locally that would likely be all the compressor I would ever need. 2HP humongous Wagner motor runs either 110 or 220(I have 220 in the shop) Dual stage(I think) and maybe a 50 gallon tank(4' long horizontal model and about 23" in diameter). It needs two belts and is currently not wired and not operational.
My inspection questions are as follows:
1. I'm new to big compressors, but this one, the compressor flywheel/pulley spins pretty freely. Is that a sign the rings are shot or do they all do that? My precious two yard sale small compressors both did the same thing, but they could've been shot too. The most recent one would generate 90 psi though. How would you "test" the "compression" of such a unit anyway??

2. Is it possible to inspect the innards of the tank with a bright mini LED maglite through he pipe plug hole? Can't imagine one of the older tanks like this rusting through, but if there were thin spots, wouldn't they be on the bottom? Would tapping lightly with a hammer reveal a change in pitch that might detect weak parts of the tank?

3. I hate to even ask, but if replacement parts are available for this unit, is it cost effective to rebuild the compressor, or find a new unit for the tank when the time comes?

I'd need to be able to run a small sandblaster(intermittently, as I'm not in a big hurry or trying to use this in a business sense), maybe a bead blasting hood, and air tools, but only one item at a time. The copper in the electirc motor has to be worth $100 or more by itself, so ifg I can get this thing for $175, am I going to get burned somewhere down the road?

Thanks in advance for your collective expertise.

DM&FS

 

[Davefr]

I'd keep shopping.

In my experience you should definitely feel compression if you turn the pump by hand unless it has some sort of unloader valve stuck open.

I think your chances of finding parts are slim to none.

The best method of evaluating tank condition is having it hydrotested. A first pass inspection through the port may be difficult because that plug is likely to be rusted frozen to the tank and very tough to remove.

For $175 I'd want to see it running.

 

[mrpizza]

If it has an unloader setup you will be able to turn it quite easily. I say see it running though.

 

[Dale B]

How easy is easy ? can you stick your finger in a pully spoke and spin it around ? It's either severly worn or the crank is broken . All mine will turn with my hand on the rim of the pully , but it takes some effort to overcome the internal friction and compression . I'm with Dave ,for $50 I'll take a chance , but I want to see it run for $175.