Hello everyone,

 I was giving my pump a good look over today and noticed a hair line crack in the Rock shaft itself, since it was in the garage I removed the rock just to be sure as it was very hard to tell, the crack goes long ways down(  around the shaft )the shaft from the ram splined end of the shaft.

The question I have is has anyone ever seen this happen on a schwing rock shaft and also the rock valve is 100% so I'm just going to change the shaft has anyone any tips on replacing the shaft itself.

Thanks for and advice or tips.

Here is the shaft im talking about circled in the picture its welded into the head of the Rock, if anyone was wondering  what i eas talking about. 

you need to replace the complete rock, if you gouge the shaft out, the alignment of the shaft to the rock will be off. that's just the way it is, but all the extra work trying to get the shaft out is not worth the time. when you do replace the rock, be sure to get all new orings and seals

Thanks very much for the reply, i can get a new shaft from schwing but was wondering was it a big job to remove the shaft  and get the new one 100% aligned, so you reckon a shaft and rock complete is the way to go even with the huge price difference of just the shaft on its own compared  to a complete unit

We have replaced many shafts.  It is time consuming removing the old shaft but not too bad, and installing the new one according to the directions from Schwing is pretty self explanatory.  Haven't had any alignment problems in the past.

That's sounds promising, I'll ask Schwing for the alignment procedure but as you said its fairly self-explanatory, measure twice cut once as they say, Mark everything before removal.

Any progress on the rock shaft