self adjusting clutch cat 3208

I have a white 4-180 tractor with a 3208 cat motor. The clutch was replaced a couple of years ago and has low hours on it, It appears to be a self adjusting clutch. But it is now slipping under a load. My question is can these self adjust clutch be adjusted. Iam sure if it was a normal clutch I could adjust it to not slip. Thanks