Hi I am working on a 30 year old two head machine this unit should be in the graveyard. It has 409A in hopper compressor, 408A on one side and 134A on the other side. The complaint was ice cream not coming out fast enough and product spoiling in hopper. I think the ice cream problem can be solved my using metal scrapers instead of plastic and correct me if I am wrong. The ice cream temp is 19 degress. The hopper refrigerator is working good but I do get temp difference from the front to back 37 degrees in front and over 50 in back can this be a bearing problem on the auger? Next question is can this problem be solved? Thanks Paul