I just changed my mud cups on my 58m shwing about a month ago. I didn't wash them after two pours in two days. Now they are leaking like crazy. Bad cylinders? Been washing them ever since. Can I fix it without changing them again? I tried using slick oack, but it doesn't work. Any ideas? Thanks. 

depending on the size of pours you did , you very well could have smoked the cups by not cleaning them out , what year is the pump ? And it could be your cylinders are scarred , just gotta look and see.

What do you mean by not washing them? Perhaps they were not installed properly. Or you didn't clean the material cylinders out and had mud chips left inside.

In my experience if the cups are leaking, it's time to change them. Luckily, it is a Schwing and cups are easy to change. Let this be a learning experience and clean your cups from now on. If you are worried about scored barrels, run your cup all the way down and put a mirror in your water box.

Take a good look at your pistons when you take them out. You can read them like you can read the wear of your tires. If the wear out of the piston is less than a inch its time to look at your barrels. There are people who have good experience whit a modification kit to Putzmeister pistons..

Balto and I do not understand what you mean by not washing your cups. If you mean you pumped two days with your water box running dry then I you would have burned your mud cups out. If you had water in the water box it is time for new barrels.

Washing mud cups? Do you mean spraying out the s tube or rock? If so you could have not possibly skipped that. Do you mean changing the water in the d box? this would have not done this either. If you installed them with out cleaning or grinding the outer crud off the barrels yes you could have damaged the cups when you pushed them in.. or if you didn't wash out the cylinders properly this could also. I doubt worn barrels are the cause.