I've been reading a lot of posts about lubricating the seals in lever machines. My (probably stupid) question is - when you push down the lever and the piston goes up, doesn't it leave a small deposit of grease on the inside of the group cylinder that then comes into contact with the water? Is this something that needs to be avoided? And if so, how?

Thanks,
David.

I think this is unavoidable. If you use Dow 111 or other NSF food safe grease then you shouldn't have to worry about it.

A few days ago I wrote about the yellowish color of the water coming out of the boiler, and a slight odor.
Now I think it was from the original grease which indeed was yellow and had a similar smell.
Yesterday I took out the group, gave it a good clean (to remove as much of the original grease as possible), and applied Dow Corning 111.
It seems to have made a big difference - the water comes out very clear and with no smell.

So, to go back to the original question of whether its a problem that the lubricant comes into contact with the water....I guess what Yakster wrote above is about right.

david_menashe wrote:So, to go back to the original question of whether its a problem that the lubricant comes into contact with the water....I guess what Yakster wrote above is about right.

It really isnt a problem if you have the right lube. Nor should you use too much of it. Just a light coating rather than a full on smear. You will be fine with dow 111.

Remember most of the lubrication of the seals comes from the brew water itself. Therefore you should avoind operating the lever until the machine is up to full brew pressure. Then, when you pull the lever down water is forced into the group via boiler pressure, and the seals are lubricated.

I suppose if the machine is used every day the piston chamber always maintains some moisture. If you've given the seals a light coating of 111 you should be good for a while. The only time I ever had a seal tear on my spring lever was when it had been sitting dry for a couple of months.

PC

Therefore you should avoind operating the lever until the machine is up to full brew pressure

Thanks, worth remembering - I like to get some hot water through the portafilter and to heat the cup before brewing - and sometimes I don't have the patience to wait for full pressure to be reached.

peacecup wrote:Remember most of the lubrication of the seals comes from the brew water itself. Therefore you should avoind operating the lever until the machine is up to full brew pressure. Then, when you pull the lever down water is forced into the group via boiler pressure, and the seals are lubricated.

Interesting. Does it have to be full pressure? Once there is some pressure, the water is forced through isn't it? I do like David and flush the cup/PF with water as the machine once the machine has partial pressure..

And for the open kettle machines, you should probably let the water come up to temperature before starting to pull. I recently pulled the group head off my La Peppina for cleaning and it was sitting empty for a while. The first pulls while the water in the kettle were still cool were rough, but as the kettle came up to temp and the water started to flow, things became smoother.

I may still want to pull the cylinder apart and check it next time, though, but the group is pretty to pull off the machine and clean without too much work.