Sunday, March 14, 2010

piston back together.

Because the piston comes apart, the gaskets are extremely easy to install. But because the gaskets were so hard, I was not able to get the assembled piston back in the group head. I had to take the piston and gasket apart, put the parts inside the group head, and reassemble it inside the grouphead.

gaskets compared



Here are the gaskets of the Cremina 2002 compared to the Cremina 67. On the top left is the 2002 grouphead gasket. Below it is the 67 grouphead gasket. The two are interchangeable and identical. In the center is a 67 piston gasket stacked on top of a 2002 piston gasket. To the right is a 2002 piston gasket above a 67 piston gasket.Here is a close up of the gaskets stacked on each other. They are very close in diameter, but the 2002 gasket has a slightly larger diameter.

clean parts

c

Here are the parts of the piston after cleaning, along with a portafilter.





Here is a pic of the new gaskets. They are extremely hard and seem to be very well made.

Here is a pic of the piston shaft. When I pulled it from the machine I noticed that it had deposits on it and was not smooth. It is my guess that the gasket at the top of the group head was not able to form a good seal because of the depostis and that is why I was getting a small leak. I scrubbed it the best that I could to bring it back to a smooth condition. Hopefully this will stop the leak.

Olympia Cremina 2002 has arrived!


I recently got my hands on a used Cremina 2002. It was in very good condition, but had been sitting in storage for the past four years. When I went to use it for the firtst time, a small leak developed where the top of the piston shaft exits the group head. No big deal, this is my fourth Cremina (first 2002 though), so I dont mind replacing the gaskets.
I contacted the U.S. Cremina distributor to get a new gasket set, and was notified that Olympia was no longer making the new style gaskets, and that all of the new machines would need to be retorfited with the older style gaskets (Cremina 67 gaskets). This process requires the installation of a new piston and the group head will need to be machined. The distributor has the tools to machine the group head on order, and as soon as it is in I will send the group head off to have the process done. Until then, I decided to remove the piston and give it a cleaning and lube.



Here is a pic of the gaskets of the piston. The one with the red band is for the lower groove on the piston and the one with the metal spring in it is for the upper.