Blowing Fuses

I have an older shocker set with the 280c compressor. I just rebuilt the piston in the compressor and cleaned the motor good, I hooked everything back up and I keep blowing fuses. I stared at 20 amps and went to 30 amp fuses. It wont even run a full cycle and fill the 2 gallon tank before it blows the fuse. Some times it even blowes when it starts up. Any help would be greatly appreciated!!!

I thought they normally would have a 40Amp fuse?