Olympia Cremina's coffee puck has a dent after replacing the seal?! - Page 8

Postby samuellaw178 on Sat Dec 24, 2011 5:37 pm

bostonbuzz wrote:I will be ordering that and hoping it's the right diameter.


Hold on!!Don't order that! I have the filter and it doesn't fit. I was suggesting to find something that looks like the Coava disk but is smaller. The Coava disk is too big to fit.
User avatar
samuellaw178
 
Posts: 473
Joined: Apr 10, 2011
Location: KL, Malaysia
www.compasscoffeeroasting.com: coffee is culinary
www.compasscoffeeroasting.com: coffee is culinary

Postby Vc on Fri Dec 30, 2011 1:23 am

Very interesting!
I stumbled upon this discussion tonite.

I have owned a 1988 cremina for 6 months.
The previous owner said it was rebuilt by OE less than a year before I got it.

Every 6 or 7 weeks I pop the dispersion screen by removing the pins in the lever and using a wood mallet to force the piston down and pop off the dispersion screen.
I clean the group and lubricate with Dow 111.

When I did this last nite, I noticed 2 things:

1. I locking the portafilter into the group is now difficult. That is, I have to push up a bit and then lock in (did not have to push up before).

2. I have a bottomless portafilter and I notice that at about 11:00, there maybe a fracture/channel since that is where the coffee first comes thru the screen. Occasionally it will spray from that 11:00 spot.

This did not happen before my last cleaning.

I removed the group and cleaned everything thoroughly with Cafiza (the screen was not dirty).


Help!
Vc
 
Posts: 31
Joined: Dec 30, 2011
Location: Philadelphia, pa

Postby samuellaw178 on Fri Dec 30, 2011 9:15 am

Vc wrote:1. I locking the portafilter into the group is now difficult. That is, I have to push up a bit and then lock in (did not have to push up before).


Vincenzo,
That was probably just the portafilter group gasket that came off its seat. Try checking if it's in the groove completely.

As for your second problem, I have no idea. Are you sure it's happening every time? Sometimes it just happens because *ah hem* of distribution problem of the coffee. As for mine, I keep getting that in every shot and the crater on my coffee puck was very evident after I remove the dry puck. Still can't find a way to solve that other than using the old seals..
User avatar
samuellaw178
 
Posts: 473
Joined: Apr 10, 2011
Location: KL, Malaysia

Postby bostonbuzz on Fri Dec 30, 2011 12:04 pm

I agree about the grouphead seal. My pf is also randomly harder or easier to lock in after I lubricate the group, no doubt because of moving that seal around. Keep in mind that the OE seals had marginal improvements for me, and I have a fine stainless steel mesh screen waiting for me when I get home tomorrow. Hopefully it will solve the spraying problem when I drop it above the dispersion screen. I'd love to get a typical E-61 dispersion screen with the hard metal holes on top, and the mesh screen below it, but of course they are much too big. I will let you know how things go!
LMWDP #353
User avatar
bostonbuzz
 
Posts: 780
Joined: Dec 15, 2010
Location: Philadelphia

Postby scythide on Sat Jan 07, 2012 9:41 pm

This might be related, but I rebuilt my '83 Cremina today and also had some issues with the OE piston gaskets. When using them, I noticed that water would start exiting the grouphead when the lever was only halfway up. I took off the dispersion screen and noticed that a single stream of water would jet out from the side of the pison as I lifted the lever to the halfway point, as if the gasket was not sealing all the way around the chamber. No water came out when the lever was all the way down though (so perhaps only when the water inlet is against the piston itself?). When I swapped the original gaskets back, I no longer had any issues and water would only come out when the lever was in the upright position.

Edit: Sorry, I see this was discussed on the last page.
LMWDP #361, Pharos #285
scythide
 
Posts: 25
Joined: Nov 28, 2011
Location: Poughkeepsie, NY

Postby Vc on Mon Jan 09, 2012 4:03 pm

this gets more interesting...

regarding the gasket, i find that i have to leave the portafilter in extra tight when i turn off the machine so as to "re-seat" the gasket...i find this helps, otherwise when i go to lock in the portafilter to pull a shot, sometimes it isn't smooth.

regarding the piston seals, i find experience the same, i.e., water jets a bit when i go half way up.

lastly, my machine also has leaked 10-15 ml of water while coming up to temperature. then no more leaking.
this happened once before and barb from OE suggested the seals may be dirty.

i removed the seals (several months ago) and cleaned and lubed with Dow 111...no more leaking.

now its leaking again. will remove the seals tonite.
how can i tell if they are seals from olympia or aftermarket?
Vc
 
Posts: 31
Joined: Dec 30, 2011
Location: Philadelphia, pa

Postby samuellaw178 on Mon Jan 09, 2012 6:37 pm

I think most probably they're OE's viton seals. That's because Olympia's are much more expensive and OE's actually work better when they work (from what I read). So it would make sense OE installs the viton instead of the Olympia's, unless there's a special request.

The way you can tell them apart, at least on mine, is that the olympia seals are very tight fit and OE viton seals are a tad looser. You can pinch gently on the OE seals around the circumferences and part of them will come out, not with the Olympia old original seal.
User avatar
samuellaw178
 
Posts: 473
Joined: Apr 10, 2011
Location: KL, Malaysia

Postby scythide on Mon Jan 09, 2012 6:55 pm

So I think I know the cause of my issues.

Image

Image

My piston shaft is not straight! This is causing one side of the cylinder to be tighter than the other. The original Cremina seals seem to flex more, so are more forgiving than the OE seals, which I believe is why they are working better for me. Anyone know if there is any way to fix this?
LMWDP #361, Pharos #285
scythide
 
Posts: 25
Joined: Nov 28, 2011
Location: Poughkeepsie, NY

Postby samuellaw178 on Mon Jan 09, 2012 7:00 pm

Interesting! I will go dissect my Cremina once I got home. hahaha.

Did you try unscrewing the piston shaft? They could be unscrewed from the piston face. Then see what you can do with it after you take it out... :roll:
User avatar
samuellaw178
 
Posts: 473
Joined: Apr 10, 2011
Location: KL, Malaysia

Postby scythide on Mon Jan 09, 2012 7:03 pm

How do you get enough leverage to unscrew it? I am thinking perhaps someone unscrewed it and threaded it in wrong?
LMWDP #361, Pharos #285
scythide
 
Posts: 25
Joined: Nov 28, 2011
Location: Poughkeepsie, NY