I had the same problem in addition to pump no longer being self priming. The replacement filter is different in size. No one at more wine answered my question if this was a compatible part. The replacement o ring was for the larger filter. I suggest contacting the pump manufacturer and list the problems identify the correct parts and figure out where your air leak is and how to correct it. More wine is attempting to get better tech support but they are apparently not end users so part numbers advice is well intentioned but not helpful.

The only thing I can say about air leaks I had the same problem at first and I put hose clamps at all connections and this seems to solve the problem.

I would actually think if air is getting in the outflow it would need to be put there on the inflow side. Otherwise I would think the outflow would leak as it's under pressure. I'm sure you probably could replace the o-rings. I am disappointed in the replacement pump head in that it pumps considerably slower than the original head that I replaced. But it was a whole lot less than a new pump.

I have the same problem tried again with another pump same thing The partis refurbished but I cant afford a new head. I'm a retired LA schoolteacher.

If the motor still runs it should work with a replacement head.

If the housing is cracked in any way it will not maintain suction. If the motor still runs it is likely a new head would work. If the shaft was damaged not so much.

Most likely yes. Remove the head (instructions can be found in the manual) and turn on the pump. If the motor and variable speed control still function replacing the head should put you back in business.

I would think that it should work if you replace the head

Hi Brian hard to know but that's a good place to start. If the motor still powers on but nothing is happening replacing the pump head may get it to work. If it does not power on at all the motor may have also been damaged during the fall which you may need to replace all together.