Gaggia D90 Group Gasket Size

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RKRobinson
Posts: 33
Joined: 1 year ago

#1: Post by RKRobinson »

Did I buy the wrong gaskets for my D90? I recently bought a set of Italia Gaskets for my Gaggia D90 from Brooks. Is the D90 not Italia?


I've been fighting with them for the last few days and havent been able to get any water through the group. Ive tried the recommended stack and every other arrangement I can imagine. . I tried to prime it with a portafilter. I tried different compressions.
I've checked the cut off valve and replaced the gasket, and cleaned out the piston and been able to blow air through it. Still nothing. Not a drop is coming into the group. There is some pressure that I can hear when putting in the piston but apparently not enough to pull water. And yes Ive cleaned the dipper.



Since Ive never done this before I have no reference. Still it seems I have the wrong size gaskets. Any advice? Where should I buy gaskets and what size?

RKRobinson (original poster)
Posts: 33
Joined: 1 year ago

#2: Post by RKRobinson (original poster) »

I should add this is what I pulled out of the group. The rubber gaskets were completely baked and not doing much of anything. They came out in bits. It seemed that the group was leaking and rather than replacing the rubber gaskets that sealed the group, they used teflon tape to stop the leaking. A real mess.


RKRobinson (original poster)
Posts: 33
Joined: 1 year ago

#3: Post by RKRobinson (original poster) »

Brooks confirms its the right gaskets. They said I might be blocking the hole in the brass ring but Im not. Any help out there in homebarista? Someone must have had this problem.

R

RKRobinson (original poster)
Posts: 33
Joined: 1 year ago

#4: Post by RKRobinson (original poster) »

Could it be the piston? Since its contained and there's no diagram, its inner workings are a bit of a mystery. The spring on the piston is working but maybe its not seating right? When I push the piston through and pull it up I get water, but not when I close it up and set the group. It seems the holes in the piston break the suction. Perhaps air is going through the screw at the end of the piston? Is it possible to take the piston apart?

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IamOiman
Team HB
Posts: 2154
Joined: 6 years ago

#5: Post by IamOiman »

First thing I would check is let the machine begin to boil and pressurize without the group piston installed. See if water begins to dribble from the inlet hole inside the group bore. If water does exit, then you need to play with the gasket stack height (I see a shim between the bottom two piston gaskets I think).

You also may need to adjust the height of the piston itself. This can be done when you turn the very top group casting around the big 80mm nut (after loosening the two grub screws on the big nut), and or adjusting the thread of the acorn cap nut + normal nut on the top of the rack. The lever orientation can be adjusted too as you play with the configurations, but you need to end up in a position where when you pull down the lever, the piston inlet holes will reach the small brass ring that you placed on top of the bottom two gaskets for water to enter the piston.
-Ryan
Using a spice grinder violates the Geneva Convention
LMWDP #612

RKRobinson (original poster)
Posts: 33
Joined: 1 year ago

#6: Post by RKRobinson (original poster) »

Thank you Ryan! I've havent turned it on yet. But yesterday I was able to push the plunger through and pull it back up to get some water through so that seems to work. Ive measured the holes and the height of the brass ring and I think Im pretty close on alignment. Im wondering if its the plunger itself? If its like everything else on this machine the holes are clogged. The previous owner put ptfe tape and gasket sealant on everything (but didnt replace any seals). I've gotten the bottom brass screw with the spring to work well. While Im able to get a small nail to bottom out in each of the holes in the plunger and they come out clean, but when I blow through the holes in the plunger they still seem a bit clogged with the spring extended. Should they have air flowing freely with the spring extended? Thats my guess and Im trying to seen if I can clear them more. They've been cleaned at least four times but still have little bits coming out.

RKRobinson (original poster)
Posts: 33
Joined: 1 year ago

#7: Post by RKRobinson (original poster) »

Okay Im a dummy. Heating it up did the trick. I did not realize how much pressure for the group came from the boiler. My other machine is a pavoni pub with a pump. This is my first lever. So again thanks Ryan. It heated up like a champ with only a leak in the water level gauge. On to the next set of problems.

billyc
Posts: 2
Joined: 3 months ago

#8: Post by billyc »

Hi there RKRobinson!

I'm currently restoring a vintage Gaggia lever machine and am looking for the gaskets. Where did you buy them from please?

billyc
Posts: 2
Joined: 3 months ago

#9: Post by billyc »




Looking for gaskets for this rebuild. Anyone know where I can find them?