I bought a Delta 40-440 scroll saw at a garage sale a few months ago. Tested it and it seemed to work fine. It was just a little noisy. I used non-detergent 30 weight oil in the oil reservoir.
Recently, I noticed an oil leak developing underneath on the belt side of the scroll saw. Yesterday, I took it apart and discovered the original gasket had crumbled apart.
And, I also discovered the resin block inside the head mechanism had broken in-half. Thank god for Ebay. I bought a replacement after haggling with a guy on Ebay. The resin block apparently was used in the older design. I thought about just using a block of wood but figured it might swell or something.
I sanded off the old gasket by hand with some sandpaper. Cleaned off the crankcase. Then applied some Black gasket sealant from Autozone.
Reassembled the saw crankcase. Topped off the oil. And fired her up.
Initially, the saw had a loud knocking noise and I thought I had screwed something up. But I left it running and after a few minutes, the saw noise level dropped significantly.
It now sounds like a sewing machine.
Now, the only issue is a small crack in one of the steps in the front 4 step pulley. I think I can replace it with a standard 1/2 bore 4 step pulley.
But for now, It works great!!