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I've finally picked up restoring my 1990 Olympia Express Coffex espresso machine. This is a rebadged Maximatic that was sold under the Coffex name at Zabar's in New York. It's also been rebadged as Pasquini Livietta (not the current version). Some of the Pasquinis had 53 mm groups. The other Maximatics have 49 mm groups where the portafilter is compatible with the Olympia Express Cremina and some parts are interchangeable (i.e., drip tray and grate, steam knob, top nut, bottom plate, sight glass and probably some other things too).

This thread is to describe what it's like to restore one of these great old machines. My last post in a major thread on restoring these was titled "Restoration as Discovery," and that's a good place to pick up. I bought my machine on eBay and it worked for awhile with great steaming but somewhat bitter high pressure extractions. Then steaming dropped off, I looked inside, found lots or rust and knew it was time for a frame off rebuild.



Here's that thread:

Pasquini Livietta (Olympia Maximatic) restoration

It includes an excellent summary by Sherman Chong that starts here.

My notes on what I found in teardown start here.

Since then I've had the frame and water tank bracket powder coated, renewed the chrome plating on the group, portafilter and steam wand. I've kept the repaint on the case and used RustOleum to address a few rust spots that were starting inside. I was able to remove most of the fine abrasion marks on the face plate and top by hand polishing with Simichrome. That stuff's terrific! Although the Ulka pump still works I ordered a Fluid-o-Tec pump to replace it because these are said to offer close to ideal brew pressure. I'm attaching the Fluid-o-Tec companion bypass valve which has a dial setting to further control brew pressure. Attaching the bypass valve wasn't obvious, but Stefano at http://www.epressocare.com suggested I remove the snout fitting on the right and it hooked right up. Now I'll have to go to Radio Shack to source a 3 amp rectifier diode to make the pump quieter (added: as corrected by Eric below and acknowledged by Fluid-o-Tech the diode is needed for the pump to work and the Radio Shack spec wasn't clear enough for the FOT engineer so I got their part -- see below).



The original Olympia Coffex PSTAT got swapped into a 1987 Cremina I recently restored but the seller of that machine found a wonderful vintage Olympia PSTAT that came back to life very easily. I propped that old PSTAT upright, filled it with a 1:1 dilution of white vinegar and let it sit overnight. Then I rinsed the inside with water (being careful to leave the microswitch dry). I used some baking soda and water on a Q tip swab to clean the top, polished the brass a bit, fastened it in place and hoped. It works perfectly and adjusts easily.



I replaced the original wiring with the Orphan Espresso wiring harness upgrade to save the time of figuring out what plugs in where. A couple of the tabs had come off so I had to do some sleuthing but got it hooked up and working only to realize I'd installed the On/Off and Brew switches upside down. The clue is the legend on the front plate.



My next post will continue some of the rebuild details and other "improvisations"!

Now that I've restored several machines, it's helpful to have tools, supplies and some spare parts available. It saves time to have some of what I need on hand to improvise. For example, I ordered replacement feet from Orphan Espresso only to find that the holes on the frame are larger than where the screws on the generic feet would attach. Two sets of hollow punches, some thick gasket material and Teflon helped me solve that. I punched some thick gasket material to center the top of the foot in the frame hole and used some thick Teflon with a screw hole punched in the middle to secure it in place.



Similarly the new filter for the water tank does not attach the same way the old one does. I improvised a way to fit that, and it works. Here's a thread with those details.

Olympia Maximatic / Coffex / Pasquini Livietta Water Tank Filter Workaround

My other restorations are mostly on lever machines, which are generally simpler. I'd never dealt with a three-way valve before. Because my first disassembly photos went unrecorded I got help from H-B member Eastsideloco to figure it out. Thanks, David! Here's that brief thread:

Olympia Maximatic / Coffex / Pasquini Livietta 3 Way Valve Reassembly Question

Compared to the Cremina there are more tight spaces and precise pipe alignments. For instance the pipe connecting the HX with the boiler must align precisely and the end that inserts into the HX fitting relies on thread lock. These must be fitted in the same sitting. It's the short bent pipe on the top.



Fortunately I had Loctite 290 thread lock on hand which I'd gotten to seal a few boiler pinholes in the Cremina. Also ever since my Conti Prestina restoration I've relied on Loctite Food Grade Antiseize compound. That project included an epic struggle with removing rusted bolts. So any screw or fastener that can seize up or rust now gets slathered with that stuff. The only place I want a bare screw touching bare metal is the grounding connection to the frame. For this I file a powder coated hole to expose the metal and find a screw a little bigger to attach. Then I check for continuity with a multimeter to make sure the grounding works.

The Prestina project also involved a struggle trying to polish steel so I now have a healthy respect for avoiding scratches. Any fitting that connects with polished steel gets seated on a Teflon gasket I create with hollow punches. I've adopted another standard practice for dealing with parts that have been descaled or otherwise need a quick clean-up. Some wire brushes on a rotary tool quickly do the job. I try and avoid metal polishes that then require an extra step of removal to avoid contamination of items that may contact something I ingest. The bracket that holds the safety switch on the bottom of the machine had so badly rusted I treated it with Naval Jelly rust remover before a thorough rinse and a polish with the rotary tool. This wore it too thin so one of the arms snapped during installation. A handy Teflon spacer now holds it securely in place. Here are before and after photos:





The water tank bracket was so badly rusted that when it returned from bead blasting and powder coating, there was a pinhole and weakness on one surface. I used JB Weld to smooth that surface. After it set overnight I sanded it. The powder coater had provided some tinted powder for touch-ups, so I mixed that with acetone, applied it and let it sit overnight again. Now that surface is much more durable and the patch is hard to see on the top of the bracket.



The main rust damage was where the boiler base started losing its seal. It was previously "sealed" with automotive gasket maker, real quality work!



The original power cord was held in place with one of those professionally installed strain relievers that requires a special tool I don't have. I replaced the power cord with one obtained at Orchard Supply Hardware, threaded it through with a round grommet and secured it in place with a cable holder bought at Fry's Electronics. I secured all of that with cable ties to hold it securely in place. All of this required threading things through with big hands in a small space and required patience. Similarly when a quick release tab comes loose from a wire I now crimp and solder it in place and use heat shrink tubing to reduce water exposure.





My next post will bring you up to date with pressure testing earlier today.

Pressure testing today went well. There was a small leak in one fitting, which I tightened up. Later I noticed a small occasional steam leak that was so quiet it sounded like a sigh. I noticed a small amount of fogging occurred near the pressure safety release valve over the sight glass. I prayed that it was the pressure safety valve because when I went to check the sightglass fitting on top, there's no way to reach it with a wrench without removing the face plate. This would require detaching the group first, then unthreading two long, skinny screws on the bottom that are held on by tiny nuts that can easily slip and get lost. After cooling the machine a few turns of a hex key inside that valve. Whew!



I find it easiest to pressure test a home machine on the kitchen counter so the machine can heat and be watched while I'm doing other things. My trials with testing the Baby Lusso taught me to put it in diapers for such a test. I also plug these machines into GFCI outlets so a short will quickly cut power.



First I primed the pump and then saw the water exiting the group was a bit cool. It's a dragon, which means at first water comes boiling out of the group and you flush the group while counting to get to the right temperature. Adjusting the PSTAT was easy. I attached an Orphan Espresso steam wand manometer and opened it to set pressure at about 0.9 bar.

Since I'd used this machine a lot, pulling the first shot was easy too. I counted four seconds before locking in the portafilter dosed with 17.5 gm of Red Bird Espresso and ran that for about 25 seconds. The pour was even and it came out quite good. I used the grinder setting marked for the Isomac Amica E61 pump machine I sold a few months back. The taste was just slightly bitter, steaming is adequate but not strong, so there's a little more work to do. I'll soon install the Fluid-o-Tec pump. I'll set the pressure a bit higher and the pump's over pressure valve (OPV) should optimize brew pressure at about 8.5 bar. I'll tune that by taste.

This will be my only pump machine (for now -- never say never!) and it will live in my office. Now that my skills have improved by a couple of years I'm surprised at how easy it is to use. My next posts will show completion steps.

Great looking rebuild, drgary. The pstat that you have installed is especially nice in how it has a label to show directionality (i.e. Counter clockwise for more pressure/temperature, clockwise for lower pressure/temperature).

Brew temperature is decoupled from boiler pressure, so the trade off of running at higher pressure is ultimately less significant than it would be on a non-hx lever. I run at 1.1 BAR because it gives the best compromise of flush volume to stream power - it's the lowest pressure setting that still provided sufficient steam for my cappas and lattes. During some informal testing, I found that 2, 3 and 5 second flushes correspond to hot, medium and cool brew temps (202, 200, and 198°F respectively), and intra-shot temperature stability was within 1°F for the duration of the shot. I ran some lungos to see how long it would take for the temperature to rise, and noticed that it started to creep up around 35 seconds, going up 2°F by 45 seconds. This is different behavior than heated groupheads like the Bezzera BZ07 or Strega, where you can effectively run shots for 60 seconds.

Now I'll have to go to Radio Shack to source a 3 amp rectifier diode to make the pump quieter.

The Fluid-o-Tech pump requires this diode to simply work and FOT sells a connector for the pump which includes the proper diode and 12" of wire w/ stripped leads all connected. The P/N is 3050090.

See this for more info on the FOT pump - Vibe pump question (related to low-flow at brew-group)

Thanks, guys. I couldn't have had two better responses. PSTAT dialing up, diode on the way! BTW I checked and discovered that my pump connector does have the flow restrictor RAS identified in the thread Eric just linked, showing these photos.





I was thinking of installing the FOT bypass valve in line with the stock Olympia fitting the way jonny did here. Is that redundant?

Is that redundant?

Yes. Now all you need to "work on" is a proper mounting arrangement for the FOT pump.

Eric:

No one I could find online sells the connector with the diode included. I've written to Fluid-o-Tech to locate a U.S. source.

I found this part at the local Radio Shack that seems to match what I've seen described:

6A, 50V Rectifier Diodes (4-Pack)
Model: 276-1661 | Catalog #: 276-1661

The price is right -- $2.99 for the pack. It looks like this.



Otherwise Espressoparts lists the type of diode needed: "FR306 DC or FR307 on terminals 2 and 3." They don't stock it or have a source. Searching FR307 on eBay locates 10 packs that ship from China for low cost, but why wait two weeks? I'll get my part at Radio Shack unless it's the wrong one.

Added: I talked to Sean at the Fluid-o-Tech Connecticut office and he didn't see enough spec info on the Radio Shack to know it would work. Their general phone number is 860-276-9270. He sold me the connector with the pigtail wire leads attached and the diode built in, which should run me about $15 shipped. That connector will give me a cleaner installation. He also acknowledged that the diode is needed for the pump to work. He didn't recognize the part number provided by Eric.

A note on gaskets:

When I disassembled the machine I discovered the previous gasket replacement was mostly with automotive gasket forming compound.



I cleaned that off and installed proper gaskets and o-rings all around. When installing the boiler gasket supplied by Orphan Espresso I was surprised that it compressed easily and started to deform, so I backed off the tightness of the heating element bolts It's held up fine without leaks. I've tightened enough that the gasket has spread somewhat beyond the outer edge of the lip and had to snip off a bit to fit the water tank bracket to the machine's base.



Here's one thing I wouldn't do next time. To polish scale off parts of the boiler I used a sanding wheel on my rotary tool. It took off the plating along with the scale. Brass won't rust so this won't hurt the functionality of the machine, but still it's a "learning experience."

Now that it's pressure tested and dialed in on the old pump I might as well run it with the case on. This is a very satisfying point in any restoration.