Old DeVilbiss Air Compressor

I have a Devilbiss 130 compressor pump. I got it from my Grandma after my Grandpa died. The tank has a plate on it that says 1949! My question is, the compressor pumps to about 20 psi, and then it starts to slow down tremendously. When I got it, it had a 1HP electric motor on it. I thought that the lack of power was the reason that It was slowing down, so I bought a 3 HP motor. Well, I installed that, and it does exactly the same thing. Any ideas? Is it supposed to slow down that much? It seems to hit a plateau at 20 psi. It pretty much stops building pressure at that point.

Thanks in advance for your help.

Kent

That old air compressor is a beautifully simple mechanism. One of the things that taking that apart and putting it back together did for me was to create a greater appreciation for the engineers of old. I will say that they must have been a little spoiled by using such tough materials as solid iron and steel. Newer air compressors are all made of Aluminum with iron parts in key places.

Here are a few pics of the old beast. She is awaiting a new paint job. I am thinking about Black with Flames ;-) Anyone have any ideas?

• Old Compressor Photos