Craftsman eccentric pin to motor shaft connection question
I have a 25 year old Craftsman/Devilbiss twin cylinder oil-less 6 HP 33 gallon compressor (model 919052930). Bought it new, and for the most part it has been adequate for my needs except for when running a zizz wheel (which I don't do very often anyway). 6 months ago when I flipped the pressure switch to turn it on it fired up with a hellacious amount of rattling and banging. Turns out it had broken both connecting rods. I've been using my smaller portable compressor for the last 6 months, but finally got around to taking a closer look at the Craftsman. The parts I would need aren't available for the model anymore. After giving it some thought I decided I might just take the motor and remount it on a new top plate to turn a belt driven 3 HP Campbell VT4923 compressor pump I can get new for $200 online. My motor is a 230 volt AO Smith rated at 14.0 amps, so seemed to be capable of turning the 3 HP pump. If not I figured I could always slow it down some with a smaller pulley on the motor. The trouble started when I began breaking everything down to make sure that the motor was indeed compatible shaft wise with a new drive pulley. I don't know much about motors from a build standpoint.....I've mostly just matched them up and replaced them in blowers, fans, and such. Never dealt with one that didn't have either a keyed or flatted shaft. The first thing I noticed on the one off the Craftsman was that there isn't a bell on the drive end. The oil-less pump frame serves as the bell so to speak. I figured I could probably come up with a bell at Grainger or a motor supply place. But then after I took the connecting rods and counterweights off of the eccentric shaft/pin I noticed it was attached to the motor shaft in a way that I don't quite understand. After looking at some exploded parts diagrams online for my model as well as some similar 2 cylinder Devilbiss models I'm beginning to think that the shaft is some type of proprietary affair that is made for direct-drive oil-less compressors only. My only hope was that this odd-looking 1 inch shaft with an eccentric pin hooked into the side of it and held in place by the counterbalance which I imagine is pressed on to the shaft.....I hoped that maybe this whole assembly was somehow mounted to a conventional 5/8 inch shaft back behind the pump frame...and that I could then extend the shaft far enough out to put a pulley on it with the use of some type of coupler. But the more diagrams I see online the more I doubt it. I was hoping someone on here might have some insight into this, possibly having taking one apart themselves. The closest motor shop is 35 miles away and I just wanted to avoid the trouble of driving there only to have them laugh and say there's nothing you can do with this motor like you want to do.