I have a friend that just purchased a Chipper and we are having some trouble with it. It is an Asplundh style drum chipper. Cant find a maker, not sure if its Whisper, Altec, Mitts & Merrill or another. It has a steel plate under the drum that is spring tensioned that I assume controls the feed rate or chip size. Correct me if I am thinking wrong here. I had a disc style but have never messed with a drum chipper. Anyway when we put in a piece that is 3" or so in diameter it will only chip about 3 feet of it and then it stalls/ slips the belts. It has a Ford industrial V-8 on it and it runs good. Does anyone have a manual or procedure for adjusting the bottom plate on this style of chipper? Thanks.