I recently replaced all the gaskets on the Olympia Cremina 67 lever machine. In doing so, I unwisely fiddled with the temperature wheel. Since then, my shots have tasted sour. I rented the boiler gauge and got it to 1.1 bars or more, adjusting the pressure to get rid of the sour taste. Nothing seemed to work.

I know that the sour taste is supposed to be a sign that the temp is too low, but as I said I have tried raising the temp as well. Also, after the light comes on, I do allow the machine enough time to get back up to temp. I'm a little perplexed and am missing my old taste!

Any advice would be appreciated.

Peter

Just a thought,
Try giving the machine a few less than full pumps, meaning move the lever till just before the water would flow. Do that a few times to get the group up to temp before locking in the portafilter. With poor seals, there may have been enough leakage to get the group to temperature without the fiddle. I find that I have to give the machine a full flush and a few false pumps if it was turned on less than 20 minutes and then at least one flush.
I use one of Orphan's temperature strips to assure my group is hot enough.
A thread about its use
Click Here
-Richard

+1

Thanks for the tip. I think my shots are getting better. If I may, I'd like to run through my procedure for pulling a shot and see what you think:

1) Turn on the machine. Wait about 10 minutes for the light to go off, then release false pressure through the wand. A few minutes later the light turns off again.

2) At that point (maybe after several minutes if I'm doing something else), I flush water through with about 5 pumps until the light comes back on. I dry the P/F, empty the cup, get ready, until the light goes off again.

3) At this point I grind my beans and insert P/F into group head (not locking it in until the handle is a little more than halfway up).

4) I raise the lever to the top and give a few tiny pumps until a few drops come out, then I pull my shot.

Does this sound right? And what you're saying is that if that if the machine hasn't been on terribly long, I should do more work at getting the group head hotter?

Thanks for your help.

The basic procedure sounds fine. In my experience the extra small pumps are unnecessary and could potentially cause problems with the coffee puck. The group head heats up so fast that if your first shot is sour it should be perfect the second shot. I find that after 3-4 shots its to hot and needs cooling. My method is flush, insert portafilter, lift lever, count to 10, lower lever - fantastic shot. If you want to set your pressure yourself, with confidence, buy a pressure adapter and gauge from Richard Penny.

"snip.. If I may, I'd like to run through my procedure for pulling a shot and see what you think:"

***I also agree with the response above as to group heating. Because I am usually pulling for myself and at most one other person i may use the methods below. The second shot of most lever machines is often the best because the group is at perhaps the best temperature.!***Boiler pressure is a correct way to set the pressurestat. The gauges may also be rented from some suppliers***RP

"1) Turn on the machine. Wait about 10 minutes for the light to go off, then release false pressure through the wand. A few minutes later the light turns off again."
***yes

"2) At that point (maybe after several minutes if I'm doing something else), I flush water through with about 5 pumps until the light comes back on. I dry the P/F, empty the cup, get ready, until the light goes off again."
*** A few false pumps. No water comes out unless you wish to clean the bottom of the portafilter basket. A final full pump will also heat the portafilter...a good thing!
( The way the group is plumbed to the boiler, there is water above the piston. When the lever is raised, the water is returned to the boiler and when the lever is lowered more hot water comes from the boiler over the piston. When the lever is raised to near the top of its stroke, that allows hot water from the boiler to enter the group below the piston. This is the water used to make the shot when the lever is lowered)

"3) At this point I grind my beans and insert P/F into group head (not locking it in until the handle is a little more than halfway up)."
*** Yes.

"4) I raise the lever to the top and give a few tiny pumps until a few drops come out, then I pull my shot."
*** Yes. Although depending on your roast and grind, the waiting for the first drop pulls may be un-necessary.
OR, even not a good thing. There are some roasts and beans that will swell quickly and may choke the machine. In those cases, to have enough grind in the basket for a correct ratio of water to grind for the correct time of the pull, I use the following method. Instead of waiting for the first drop with those roasts, I generally may accept less brew and only do a single pull.

"Does this sound right? And what you're saying is that if that if the machine hasn't been on terribly long, I should do more work at getting the group head hotter?"
*** You have the right of it!

"Thanks for your help."
***You are very welcome! Remember that after three years I am still learning to use the Cremina.
Many Happy Pulls!
-Richard

Richard Penney said "There are some roasts and beans that will swell quickly and may choke the machine. In those cases, to have enough grind in the basket for a correct ratio of water to grind for the correct time of the pull, I use the following method. Instead of waiting for the first drop with those roasts, I generally may accept less brew and only do a single pull."
---------------------
This point is OFTEN overlooked!
Every blend/SO is different: add in the roasting method, roast degree, age of the roast, etc and you have to throw the "one technique fit's all" thing out the window.
For consistency (for me) I eschew extra pumps and such, as that seemed more like a spring lever sort of thing.
A one and done approach, like Richard performs has given me the most consistent results. YMMV

BTW, Richard is being way too modest. His tampers and other paraphernalia are used by many around here.

PKR wrote:
2) At that point (maybe after several minutes if I'm doing something else), I flush water through with about 5 pumps until the light comes back on. I dry the P/F, empty the cup, get ready, until the light goes off again.

On my Cremina fve pulls would have overheated the machine, and my pstat was set low, around 0.8.
But maybe I don't understand what you mean by "with about 5 pumps". Are these part-way or full lifts of the lever?