Gaggia Classic rebuild

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

#1: Post by Rex1027 »

Hi all first post, I picked up a Gaggia Coffee Classic for $25 last night and I am currently doing a rebuild. The machine powers on and gets hot, but needs a good cleaning. It's dated 1997 I've already ordered a bunch of parts:

Top half boiler
New baskets
New water tank tubing
Tank lid
Rancilio steam wand
Steam thermostat
Water thermostat
Group gasket
Shower screen
Brass dispersion plate

I'm having trouble removing the green stuff(lime scale?) from the brass parts, I've soaked them in Cafiza. any tips?

Let me know if you guys think it'll need anything else.


tracer bullet

#2: Post by tracer bullet »

That's a lot of parts, you'll probably be good. Most things can be disassembled and cleaned and made to work including the OPV and such. I'd just see what works and fix / replace as needed. You won't go wrong with what you ordered but might not have needed all of it.

Be sure the gasket between the boiler halves is good.

I cleaned parts with 0000 steel wool in some cases, or 1000 grit wet / dry sandpaper. Might consider that on some of your mating surfaces, the sandpaper - with a piece of glass underneath or perhaps something like a marble counter top - to be sure they are flat.

Have fun!

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#3: Post by nirdvorai »

Nice find.
Try to use citric acid mixed with water or descale solution to clean the scale.
Cafiza is more for backflush or cleaning the portafilter and shower disc.

You might need new gaskets for the 3 way solenoid and the OPV.

Good luck.

Rex1027 (original poster)

#4: Post by Rex1027 (original poster) »

Do you know where I can buy these 2 gaskets?


#5: Post by Alslaw »

They look like simple o-rings. If you bring the old ones to your local hardware store, you can probably find replacements for pretty cheap.
LMWDP # 606


#6: Post by SJM »

nirdvorai wrote: Try to use citric acid mixed with water or descale solution to clean the scale.
Cafiza is more for backflush or cleaning the portafilter and shower disc.
What he said, but somewhat more emphatically:
Cafiza is a detergent and won't do anything for scale.
Use Citric Acid for scale (which may occur anywhere along the path of the water through the machine)
Use Cafiza for stuff that is external to the waterpath but contaminated with coffee oils (portafilter, shower screen, etc).

Backflushing is to get that one small portion of the machine which is internal but gets coffee oils too when water is pushed back up from the puck. For that? Right....Cafiza.

Just by the way, the brass dispersion plate is not a worthwhile expenditure. If you just want the bling, go for it, but it performs no better than the original showerscreen.

And, finally, although it is no longer active, there might be helpful information for you at the old Gaggia forum

Rex1027 (original poster)

#7: Post by Rex1027 (original poster) »

Thanks for the replies, great info!

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#8: Post by AZRich »

Not much to add to the other good advice posts, but one word of caution. If you remove the switch panel from the front face do not pry it off but only compress the clips on the back to remove it . From experience, (ahem..) a little prying from the front can result in broken plastic and switch parts flying everywhere! Your boiler looks good from the outside so likely did not need a replacement, just a descale. The brew thermostat has a wide deadband, and for < $50 a basic PID with SSR and bare wire TC I think is a very worthwhile and simple upgrade to bypass that thermo.