Thursday, April 14, 2011

Overhaul of Gaggia Classic Espresso Machine

A couple of years ago, I gave my father a Gaggia Classic espresso machine for Christmas. The Gaggia Classic is, in my opinion, the best value for a home espresso machine that uses a commercial type portafilter and has good frothing abilities. The only thing this machine is lacking is a double boiler - but that would significantly raise the cost of the machine.

Unfortunately the hard water where he lives clogged it up. This happened on my machine as well after about 4 years. The symptom is lack of pressure when it is on the brew cycle - but the pump is still able to pump through the frothing wand.

The cause is a clogged three-way valve and/or brew group. This shows how to fix both.

Here is the subject:


Cleaning out the three-way solenoid

The first thing you should do, obviously, is take all the loose accouterments off the machine. I then ran the pump for a few seconds to pump water out of the system, not specifically required, but it keeps water from leaking on your work surface. Definitely make sure it is unplugged and cool before attempting to take anything apart.

The machine enclosure is welded on all sides, so access is through the top. To gain access to the machine, undo the two phillips screws on the top of the machine:


You will then be able to access the insides of the machine. Looking at this machine it is really a marvel electronics are still made like this. It is like a 1960's Fender amp with point-to-point wiring - except the Gaggia has removable connectors at each point! The wiring and connectors are all ridiculously overbuilt for home use. The removable wiring and components also makes the machine easy to rebuild and maintain (like cars used to be).

To make some room to operate, I unplugged the wires from the on-off switch and also the side of the three-way switch (It is the black cube piece with the yellow round metal label on the top - this is what you are trying to access). You should write down which color wire goes to which connector so you don't forget!


Remove the tube from the top of the three way solenoid. I used needle nose pliers to squeeze the hose clip and then pulled off the tube.

Now you can see the three way solenoid at the top center of this picture with the tube removed. Remove the 14mm nut, washer and yellow metal washer. Slide off the magnet (the black cube)


Now remove the two 4mm allen bolts from the front of the brass piece holding it to the machine chassis.


These will be a bit of a squeeze to get your hands in there with the allen wrench. Now you can remove the brass part of the solenoid.

Here it is:


Look in these two holes, then take a pin or other small metal piece and clean out all of the scale. The hole on the right is the real problem as it has the smallest aperture and is prone to clogging.

Now you have to take off the large brass nut and clean out the insides of the solenoid. I found the best way to do this is to screw the solenoid to a 2x4 to be able to apply torque to the assembly. I think this bolt is a 23mm nut, not having a metric wrench that big - a 15/16" wrench will also work.

Here it is attached to a 2x4 with the wrench. I used some drywall screws to hold it down:


Now you can see the two small apertures inside the solenoid:


Clean these out well with a pin or other small metal piece. Make sure the spring mechanism will move in its sleeve.

As they say, reassembly is the reverse of dis-assembly. Make sure all of the wires are firmly back on their terminals.

Cleaning out the brew group:


Turn the machine over and remove the phillips screw holding in the shower screen:


Remove the two 5mm allen screws holding the brew group together:


Now remove the gasket. This is best done by using a screw to pull it out. Screw in a wood screw, then use pliers to pull out the gasket.

Screw in drywall screw to gasket and pull out:


gasket removed:


Now you can remove the brew head. This can be easy or hard depending on how much scale is holding it on there. This is my second time doing this. The first time I had to gently pry it up (put the pry device where the arrow is in the next picture) this time, it just came right out.

I have read other places where they suggest adding some de-scaler here if it is hard to remove - or threading a longer screw down the center to push it out. I did not have that much trouble getting it out.


I took a brass brush to remove all the scale in the brew head. You can see a small hole where the water is introduced. This area usually has more scale around it - clean it all out:


Once everything is cleaned out, insert the new gasket and bolt everything back together in the reverse order.

Run a cleaning cycle with de-scaler, then you are ready to go for a few more years of service!

33 comments:

  1. Fantastic guide, thanks! My machine doesn't get scaled as we're in a super-soft water area, but it had been leaking around the brew head collar for some time. As it's over 10 years old, I suspect the gasket has had it, so using your pics, it was easy to whip it out.

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  2. Hi I've just read your post and it got my Gaggia Classic back up and running ;)
    I live in a hard water area and I gave it a de-scale but still no joy so pulled out the whole boiler assembly, put back together yet still no joy so found your thread and pulled out the square black thing (what is it?) and found a very small piece of very hard scale.
    Put back together and wow yes it works ;)

    Thank you for your time putting this site together it helped a lot .

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  3. my gaggia classic had no water from brew group (just a tiny drop getting through) but steam from spout. some other posts were not very clear but the advice above is excellent, really helpfull, clear to follow esp with pics and sorted my machine out a treat :) many thanks

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  4. Excellent guide... I had a small chunk of black (gasket or O-ring?) material which was in the solenoid right where you said it would be (we had the same symptoms of lower pressure from the brew group but full steam and/or water flow from the spout. It really is amazing that you can have so much flow through such a tiny hole in the solenoid... in hindsight an obvious contender for easy blockages. Earnt major man-points for fixing it! Many thanks!

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  5. glad it is working for everyone. i have done this procedure many times in the last few years and it works great. an inexpensive solution to getting a great machine back to top shape

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  6. Thank you for your time in putting this guide together, it gave me the confidence to fix my Gaggia Classic when it stopped producing water. There was not a lot of scale to be found, but as soon as I switched it on after re-assembly, it worked!

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  7. Thank you very much for this detailed description. I have a couple of questions. In the final step you mention putting in a new gasket. Do you mean replacing the one you took out or actually getting a new one? If a new one, where would I find that?
    Second, I find that when I am steaming, water continues to come out of the brew head. Not is much as if I am brewing, but still it is coming out. Any ideas on what might be causing this? Thanks very much.

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  8. Debk: You should replace the gasket with a new one. Like a lot of rubber gaskets, they get old and hard over time. You can buy a new one from whole latte love (call and ask for parts) or espresso zone website. As far as the water coming out of the brew group, you might get a few drips as residual water comes out, but it should not be any kind of water flow. It might need a new three-way valve to correct this problem.

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  9. Great advice. Just followed your instructions. Machine now working better than ever. Thanks for taking the time in posting this solution. Saved me a bundle + can have great tasting coffee again.

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  10. Martin, glad it worked for you - thanks for the feedback.

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  11. Just to join with all the rest in saying thanks for saving my gaggia - it had got slower and slower and finally stopped, despite descaling. It followed your excellent pics and despite having no idea what a solinoid does or is, managed to dismantle it. No scale was visible but I soaked it anyway in vinegar - something must have been there because on putting the whole thig back together, flow was restored. I have ordered a new gasket so the brew head will be my next challenge!

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  12. Thanks for all the info and photos,easy to follow and a complete success.I found it easier to remove the two allen keys first ,so that you could remove the solenoid as one complete unit and than work on the bench, but again many thanks your guide got me started.Now whose got a coffee machine that needs repairing??

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  13. Thanks for this! It was as easy as you made it look and it didn't cost me a lot of $ to get things going again.

    Steve

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  15. Thanks for all the comments. A follow up on a recent repair. I had a situation where the flow completely stopped but the pump was still energized. Removed a big chunk of scale from the 3-way valve using the above procedure and then it performed as intended.

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  16. Sunday morning disaster averted!. Water was coming out of the steam wand fine but very limited out of the brew head. Dismantled 3-way valve and the blockage seemed to be in the long thin part of the valve (near where the black tube attaches). Cleared with a pin and now working fine. Thanks for the good advice.

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  17. Thanks mate. This is the post that keeps on giving.

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  18. Many thanks for the excellent guide which I found very straightforward to follow. However, I was not able to solve my problem. I am getting hot water and steam from the wand but no water from the brew head though the pump sounds as though it's working. I followed the cleaning advice for the solenoid even though there was no scale evident. I also cleaned the brew head as instructed. I would be grateful for any further advice.
    Thank you for your time


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  19. I today picked up a Gaggia classic for free from freecycle with the understanding it didn't work. A quick insoectikn suggests its in dire need to a proper clean and descale, so your post is just what I need.

    To the previous commenter, this blog post is for an even more thorough strip down, so might be worth a try:

    http://protofusion.org/wordpress/2012/04/gaggia-classic-disassembly-and-cleaning/

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    Replies
    1. Thanks Dan for your input. I did the complete strip-down yesterday, very straightforward with the help of this excellent blog.

      I'm just about to reassemble so praying hard to the Coffee God !

      Good luck with your project, Dan !

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  20. Hi Chris,
    This is the best step by step guide to cleaning a Gaggia Classic on the web and the only one to include cleaning the solenoid. Thanks a million - just fixed our 3 year old machine without another trip to the service agent. Cheers, Joe

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  21. thanks for the comments. also took a look at the other site with the complete boiler removal and dis-assembly. in doing dozens of machines, the low performance issues can be solved by cleaning out the 3-way solenoid as the prime problem. there is certainly a lot more to take apart, but this is the weak point in the design.

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  22. A huge thank-you to you, Chris: I once again have schiuma on my espresso after several days of tossing out cup after cup of a bitter, tarry substance claiming to be coffee. Despite my best efforts in cleaning out the usual bits, the pressure just wasn't there anymore... until I followed your guide. My Classic is 13 years old (with one or two younger parts in the group head), so it was well due for an internal cleansing!

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  23. Great guide - many thanks. My 9 year old Gaggia had, I thought, chucked it in and I was about to replace it. There was No water flow whatsoever, so couldn't run any descaling stuff through it. It's now like new.
    A couple of comments; I have a 15mm nut on the solenoid. And while getting the two Allen nuts off, getting them back on was a real strain. As well, my solenoid was very jammed and I couldn't loosen it with a pin. So I soaked it in white vinegar for 30 min. That did it.
    Thanks again. A great machine carries on.

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  24. My 1999 $10 garage sale Gaggia Classic wasn't doing well. After the solenoid cleaning I am 100% stoked!
    Rather than using a pin I inserted a short piece of solid bailing wire and heard a crunch so I knew one of the solenoid openings was blocked. This plus a 30 minute vinegar soak cleared the opening.
    Tip: After breaking loose the two allen screws holding the solenoid on, use a short flat blade screw driver to loosen/tighten the allen screws till the final tightening.
    Also to be clear...you must have a new rubber gasket for the brew head on hand if you plan to use a wood screw to remove the old gasket as described as using the wood screw destroys the old gasket.
    Thanks a million for this java-giving tutorial!

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  25. Hello Sir.
    I seem to have gotten off to a bad start following your good blog on servicing my Classic.
    On your third picture down: I tried to disconnect the two connectors to the mains outlet. (Right of pic with arrow pointing down).
    I pulled away the top connector and then tried the other, but it seem to be stuck, so I stopped.
    Then when I tried to re-connect the top connector again I found that it wouldn't. Was it soldered, and have I broke it?
    Then I tried to remove the black plastic 3-way mains module to pass it out of the casing so that I could work on re-connecting it without the clutter. I broke some of the plastic structure that holds it snug to the case.
    Do you think I should give up?
    The reason I began this journey is because I needed to replace the gasket, which I did successfully. But after pouring my first espresso which poured painfully slow, I tried using a descaler. This didn't improve anything, so I came across your blog and decided to go deeper.
    This is a machine that has sat around doing nothing for a long time and is no doubt in need of service and clean up.
    I suspect that I could take it in for a professional repair, but I suspect that the costs would be at least half the cost of buying a brand new one with a warranty.
    I would very much appreciate getting some advise from you.
    Kindest regards
    Clive

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  26. Hello Christopher,

    Thanks for your guide. It was a great help, and the best thing I have found on the internet for dismantling/ cleaning the Classic.

    David. York, UK.

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  27. Thanks for this guide. It was really easy to follow. My only problem was with unscrewing the bolts that required the Allen wrench, because they are hard to reach. Otherwise it was very easy to do. I am right now with my beloved cup of coffee in hand, thanks to your help.

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  28. Hi this one is great and is really a good post. I think it will help me a lot in the related stuff and is very much useful for me.find the best Atlanta water line repair services

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  29. Now what?? The steam wand works but no flow from the group head. I descaled, cleaned the group head, and now removed the solenoid. But solenoid was perfectly clean. The motor sounds just fine. Does anyone have a suggestion?? Thanks, all.

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  30. Hello, thanks for posting this. I have an additional tip for those who (like me) found removing and replacing the allen bolts that hold the solenoid to the body the hardest part of this process. It is easy to remove the pump (which is mounted on a flexible rubber neck toward the back of the machine) from the rail it is attached to. Simply remove the two philips head screws, unplug the two leads to the mains power (blue on top!) and shove the whole assembly aside. Then there is plenty of room to maneuver to get the solenoid allen bolts off and on. Thanks again, saved me a bundle of money and I got to impress the wife and kids with my handiness (which may be a mixed blessing...)

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