Old Gaggia Espresso - Won't Brew

Equipment doesn't work? Troubleshooting? If you're handy, members can help.

#1: Post by mbiang »

Greetings all: Hoping you can help me shed some light on my problem. I've got an old Gaggia Espresso model machine that is having trouble brewing. I've gone through decalcification, but I don't get any water flow at all. The pump seems to be running just fine. I've disassembled the shower plate, which revealed a hex nut. Removing the hex nut reveals a spring and rubber plug at the top. (photos attached).

When I run the machine without the spring, plug and nut assembly, water flows just fine. However, when I install the spring, plug and nut, no water flows out of the machine. Is my pump going bad? am I assembling something wrong, perhaps over tightening the nut? I'm not exactly sure how this "valve / spring / plug" assembly is supposed to function, so thanks for any help you can provide!


#2: Post by RobAnybody »

the spring-plug assembly is supposed to open at a certain water pressure. since it doesn't this most likely means your pump is not producing enough pressure.
As the pump still is able to pump water when unrestricted you can probably get it to work again by disassembling and cleaning the pump and changing the internal o-ring.
(see also here: Repairing a ULKA vibratory pump)
one other option is that the overpressure valve is stuck open and when the spring-plug assembly restricts the flow the water is pumped directly back into the reservoir.
this you should be able to see, just have the pump run with the spring-plug assembly in place and check if there is water coming out of the return line.
hope this helps,
LMWDP #647

mbiang (original poster)

#3: Post by mbiang (original poster) »

Thanks Rob! I'll give those both a try.

mbiang (original poster)

#4: Post by mbiang (original poster) »

Hmm... I ended up getting this to work by descaling the machine, cleaning all the disassembled parts, and then by opening and closing the steam wand valve. My suspicion is that the steam wand valve, while seeming to be closed, was somehow letting some small amount of pressure leak. It now brews as good as ever! Thanks!