It is possible that the grind you are using is too fine and causing so much back pressure that the portafilter is moving, also possible that the group gasket installed need to be replaced, I have also seen this happen with damaged screens.
Often these temperature differences are solved by descaling. Do never use vinegar. One can buy citric acid crystals or powder (not the same as lemon juice) and dissolve that chemical in water. I buy it in the Chinese Mall. Do not make a too strong acid. Shops sell maintenance powder which is the same but that is quite expensive. Let the acidic water go in and through the coffee maker until it looks clear. Next rinse with water for quite a number of runs. You may see how strong the citric acid that you make is by descaling something else and wait for about an hour. Another acid to be used in coffee makers is lactic acid. Lactic acid is bought as a cleaning agent. Also very strong and to be diluted with water.
It is most likely that something is blocking the pathway to the grinder. As the Rocky is a direct drive grinder there is no gear that could be broken.
Try to remove the beans from the hopper and inspect the pathway, move the beans that might be under the 'disk'. If that is not working you might have to open the grinder;
remove all coffee beans
unscrew the three screws in the bottom of the hopper
remove the hopper
Now you can see the grinder wheel and tell if it is turning normally.
This might be a good opportunity to give the grinder a thorough cleaning.
Do not soak it in water, just a stiff small brush (e.g. a toothbrush) is the best tool. And perhaps accompanied by a vacuum cleaner :)
If you have been using very 'oily' beans for a long time they might have clogged the grinding wheels.
Good luck,
Villi
First, I'm not a Rancilio tech but I have worked on similar models.
*** All service should be performed by a qualified technician. The following is for information only ***
* Usually one gets less water out of the portafilter rather than more (or faster). Check the amount of water on an empty shot. It should be between 1-1/2 oz to 3 oz (depending on your shot size) If this is a manual on/off shot then disreguard.
* Fast pour is directly related to the pressure setting (usually 9 bar), Coffee amount, Grind size, and Tamp (or compression). You can check most of it by following the many examples given on you tube. Water pressure is a bit harder as you will need a pressure guage portafilter.
* If your still having problems with fast shots then have your service vendor check and adjust the bar if needed.
Aloha, ukeboy57
P.S. Check if your using the right portafilter, There are many types used for different purposes; Pod, Capsule, Single, Double, Tripple, Drip coffee (Americano), Back pressure adjustable, ect.
Hi Daren,
You could replace the whole steam valve wand but you don't need to.
The rubber grommet inside the steam valve is worn out and the tap wont close properly - that is why the steam is coming out.
You will find these parts with a commercial rancilio supplier.
You need to contact a coffee technician that deals with Rancilio commercial machines.They would be able to trouble shoot.
But it would involve a call out to investigate the problem.