Help is requested

I am a mechanic apprentice, it happens that we change Cluchk to a 2002 Cavalier, which after changing it, the pedal will be after a certain use, between 300km. We apply a purge with a new liquid and achieve this distance, if I purge it and only the level, it travels half that is about 150 km or 100km, without presenting a problem, I observe that the liquid gets a little dirty, and I think that in there the problem is going, the clochk is rebuilt, since the original is between about 600 dollars or 7500 Mexican pesos

Hello, the Cluchk will be the EMBREAGUE and if every 300km you have to purge and fill in the problem you have in these options 1. Teacher with 2. Slave winder.

Thanks, I'm going to verify these options, I'm in communication

It does not have to see the 300 but the pedal is burst ,,,, if it does not boot liquid .. it would be main brake bomb ... luck change packaging I think the embolo is stuck