I started this at alt.coffee. but feel this is a better location since I will be posting a load of pictures.

This is a project to revitalize a model year 2000 Laurentis single group commercial espresso machine that I will be using at home. This machine is identical to the Astoria Argenta Junior Automatic 1 group machine. Like the Astoria, it is made by CMA (Wega, Rio, etc). I purchased the machine on ebay. The seller said it had been in a "high end gas station". This is my third espresso machine coming in behind first a Saeco Vienna super auto, then a Silvia. My goal is to get this machine working properly and to do some hot rodding and make some cosmetic improvements. More on that later.

The machine arrived yesterday April 7th. This machine requires plumbing so I performed the minimal to get that setup. I split my ice maker valve and ran the supply into the that T fitting and ran the drain into a bucket. I had a 20 amp outlet waiting, so I turned on the water, pushed the manual fill valve, then turned the machine on. I couldnt tell immediately the reading on the tank level site because I didnt know I was looking for a little black floating ball. After I discovered the little ball, I realized the machine came to me with a full tank of water (explaining the soaking wet box). After turning the switch (2 position - 0 or 1) to 1, I could hear the heating element and the telltale moaning and groaning of heating metal. I turned on the manual group head dispenser and water trickled out. I noticed the brew pressure was at about 6 bars. It drops slightly when water is moving through the system, but it does not climb. This is line pressure.

The machine heated up and the boiler pressure rose to just above 1.1 bar. This seemed about right, so I fiddled with the Auto buttons and hot water came through the brew group in a trickle. I open up the steam wand and steam came out in gushes at first, then like an F-14 in full afterburner. I opened the Americano wand and green water came out like a fire extinguisher, high pressure with a lot of steam mixed in. I pulled about a quart of water out of the boiler via the Americano wand and then let it sit for a few minutes. Loads of sediment settle in the container. I continued to run water out of the wand in hopes of cycling clean water into the boiler. At this point something bizarre occurred.

I heard a clunk that I assume was the auto-fill solenoid opening a valve to let water into the boiler. This seemed to cycling on and off several times. While this happened, the American wand started to dry up. By that I mean that only steam came out of the wand, then as the boiler pressure continued to drop, less and less came out until the boiler pressure was at 0. I could however hear the solenoid clunking on and off. I really dont know why this happened. Maybe it is related to the pump and motor not working? At this point, I knew more or less the general condition of the machine so I shut her down and planned my assault.

I have now begun taking her apart. I know that the motor and pump are not working. The pump drive shaft is quite stiff to turn with my fingers. The motor weighs more than some of my bikes so it sure seems like it would have enough torque to drive even the stiffened up pump shaft? I am somewhat at a loss as to how to test the motor now that it is removed from the machine? It seems like it may be a good idea to just get a new pump and motor?

The boiler was surprisingly clean inside. There was very little scale. Only some soft buildup around the various inlet and outlet holes and at the high tide line. The heating element was mostly clean and not deformed. Some of the pipes had some scale buildup but most did not. Either way I will soak them all in a citric acid solution. Here are the regular maintenance things I think I am going to replace:

- group head gasket
- group shower screen
- anti-syphon valve (when I took it apart it showed signs of poor repairs -Teflon tape wadded up to stop a leak)
- Pump
- Pump motor
- Boiler level site glass assembly (some hissing coming from that general vicinity and a slight leak from the top of the glass tube)

Here is a pic of the right side. The pump can be seen at the lower right corner and the motor is attached behind it. I unscrewed that pipe to drain the boiler. The outlet was clogged with junk that simply took a screwdriver shoved in there to clear:




This next picture is from the rear of the machine. The big gray thing on the bottom is the motor. Top right is the pressure-stat which inside looks very clean. I have no idea what the black box on the upper left is. That longish silver piece between the elbow and the braided hose has a shutoff valve on the other side. What is that?




I would appreciate any help or advice anyone can offer. And I thank you in advance. This is going to be an ongoing saga until complete.


Thanks,

Chris

Take the pump and motor out of the frame. Remove the pump, there should be a metal band with a screw or bolt holding the works together. Just loosen it and the two parts will separate. You should have three power leads on the motor (actually two and one ground), take a set of meter test leads, hook them up to the motor terminals (not the ground!) and put the other ends in the wall outlet. It would be advisable to have someone hold the motor when you apply power, it will want to torque to one side when it spins up.

Motors are pretty bulletproof but pumps wear out. You should also have a capacitor attached to the motor. It probably looks like a silver tube attached to the motor. If the motor does not spin up, and the shaft rotates freely with your fingers, you could have a bad cap. You may want to check it before you replace the motor.

The small black box looks like a Parker solenoid, it is hard to tell from the photos but that may be your boiler fill solenoid.

A filled boiler and heat exchanger is real bad. If the temperatures are below freezing, the water could freeze and rupture your HX or boiler. Think of a can of pop in the freezer. When I rebuilt my Faema, I put everything in a drum full of descale solution to clean it up.

Your machine is in pristine condition compared to what my two group looked like. A good descale and cleaning and you will probably be up and running.

A personal suggestion. If you are taking it apart anyway, replace every seal, gasket and O-ring in the machine. Your 1/4 ice maker waterline will probably need upgraded to a 3/8 line.

Edit....
Your switch, one position will be off, another on with no power to the heating element (so you can fill the boiler before energizing the heater) and the last power and heat. The thing I found strange on my Faema, down position was off, second position was power with heat and the third was power no heat. You would think the heat would be the last setting. It was a good thing I took a meter to everything to verify my electronics before I actually put power to the box.

If your boiler was not shipped full, you would have energized a dry heating element. A few seconds of power and you would have gotten a lowed POW as you heating element exploded.

Thanks for the reply. Your Faema project has been an inspiration for me. And due to the severe condition some people start with, I wanted to be specific that my project is just a revitalization, not a rebuild.

The boiler and HX were fine when I took the boiler cover off today. No signs of freezing and the HX has no cracks.

I actually took the motor and pump out today. The motor has two wires exiting the rear. Each wire has a connector with two little plugs ( I can take a picture). Are you saying I can simply connect two leads between these two connectors and a wall outlet and it should turn over? Even though the capacitor is not inline? I dont want to kill it if it isnt already dead.



Thanks,

Chris

Interesting. Maybe you motor does not need a cap. There should be a ground somewhere unless it grounds via the motor mount to the frame. My motor was/is rubber mounted to reduce vibration and noise. You can hook those two lines to power and off it goes. I used test leads with alligator clips. My power hooked to a terminal block on the motor so I connected the gator clips to the studs and put the test lead ends into the wall socket. Just use some common sense when doing it; you do not want to electrocute yourself.

If it does have a cap somewhere before the motor, it will simply not spin if you bypass it. You will not hurt the motor, it will simply not run.

Day 2:

The tear down continued. I removed the rest of the copper and steel pipes. I removed the front face plate with the control system and gauge in tact. I removed the HX from the boiler. I started deliming using CLR (I could not find in citric acid locally, yet). The HX, some fittings, pipes and valves got very very very clean (too clean?). The copper turned very coppery colored. I think it is ok.

Here is a photo of the decapitated front of the machine. That gaping hole feeds the group:




Here is a closeup of that hole showing a lot of green scale buildup inside. I could not get those three outer bolts loose. They hold the boiler to the frame. I may need to torch them if I really want to get the boiler off. I haven't decided yet.



Here is a picture of the group head. The gasket is spiritually bonded up in there. I am probably going to have to take a torch to it to clean it out well:



The last two pictures are the motor and the pump. The pump is still very tight (no magic happened during the evening that fixed it). The motor is as yet untested. Any more advice on testing would be great. I am still wondering... is it water cooled? Is that what the piping is about?





Next steps are to finish deliming the rest of the pipes, valves and etc. I still have to pull a few things off the frame and then hose out the boiler...

More to come.


Chris

cannonfodder wrote:Interesting. Maybe you motor does not need a cap. There should be a ground somewhere unless it grounds via the motor mount to the frame. My motor was/is rubber mounted to reduce vibration and noise. You can hook those two lines to power and off it goes. I used test leads with alligator clips. My power hooked to a terminal block on the motor so I connected the gator clips to the studs and put the test lead ends into the wall socket. Just use some common sense when doing it; you do not want to electrocute yourself.

If it does have a cap somewhere before the motor, it will simply not spin if you bypass it. You will not hurt the motor, it will simply not run.

Follow up on this: There is a capacitor still mounted to the frame. I guess testing could be trickier than just jammin the ends of the wires into a wall outlet. There was also a ground wire attached via a screw. The wire led back to a common area on the frame where many wires grounded. I may take it to a local shop to have a look at it.

C.

I'm not sure that I'm getting all of this 100%, but capacitors are so cheap that is just makes sense to replace them if they are in question ( EDIT: and would allow testing of the motor in its intended manner). Copy down the info written on them and call RadioShak. Alternatively, a decent multimeter would have a test function for capicitance, microFarads I think. Don't mean to intrude; i'm just so cheap that I hate to take things to the 'shop' for stuff like testing, etc.


cheers,
dan r.

Capacitors are cheap and you can test it with a meter and Dan suggests. Problem may be finding the correct size cap. You being in Oklahoma city, electronic specialty shops should not be to hard to come by.

The two big thing you need are the voltage and Mf off the cap. You may have an electronic schematic on the pump motor or a label with the motor spec. The capacitor details should be on that. You may be given a Mf range which might make finding a working part easier.

It looks like you have a Teflon boiler gasket. It was recommended to me to use the Teflon and not the paper gasket. When you reinstall the element, pay particular attention to the gasket. It sits on a small ridge around the element back plate. If you are not paying attention, it may slip off as you reinstall the element. If you tighten down the bolts while it is off center, you may ruin the gasket (crush it or cut it). I almost did that on my machine.

That does look like a water cool jacket on the motor. I have seen a couple of others that used a coil around the exterior of the motor for cooling. Don't forget to descale in it as well.

OkcEspresso wrote:Here is a picture of the group head. The gasket is spiritually bonded up in there. I am probably going to have to take a torch to it to clean it out well:

image: http://www.myhuevos.com/pics/laurentis/groupHead.jpg

The PF gasket is easy (well, not really, but it doesn't require a torcj) to remove. The local espresso engineers here showed me what they use. Its an awl, from TrueValue Hardware! They just poke it into the gasket and start pulling pieces up until the gasket comes apart, and then they pry the thing loose. Be careful not to scar the bed that it sits in doing this, though. It takes a bit of grunt and some patience, but it'll come.
Oh, and being that they are so cheap, the proper cap could be gotten from the CMA reps here in the states, General Espresso Equipment. And, getting the rating on the cap is important, but the voltage only needs to meet or exceed the original, it doesn't have to be exact, i.e., a 32V cap could be used in place of a 16V cap.

cannonfodder wrote:That does look like a water cool jacket on the motor. I have seen a couple of others that used a coil around the exterior of the motor for cooling. Don't forget to descale in it as well.

A couple of questions about this:

- In a pinch, if this motor is dead, could I use a different motor and just reroute the water lines that made it happen? A new one of these puppies is $350+

- I am assuming I can't just drop the whole motor in my descaling solution. Any thoughts on the best way to descale?

- Could the pump be replaced with a procon or other similar unit?


Thanks,

C.

*Just pulled a double of Capri from Caffe D'arte on the Silvia... she doesnt know about Laurent yet.

Don't know about the motor. Seeing how tight things are in there, a non cooled motor may get too hot. As far as descaleing the water jacket, just use a funnel and pour some solution in. You may want to cap the fittings with a cork or other device so you can soak it on one side, then rotate to get the other. Then empty and flush.

Pumps are relatively generic, you need the appropriate flow rate and pressure but brand is not important. Having said that, I have not replaced a pump, mine was good, so someone more knowledgeable may want to chime in.

Are you sure the motor cannot be serviced? A decent electric shop would have bearings/brushes and could re-wrap it. For 350 bucks you'd think it could be re-furbd. Alternatively, perhaps the pump is used in more mundane machines and available through a third party retailer. Just some thoughts.

Just re-read your post; what does the motor's sticker say on it? Zecchini?


cheers,
dan r.

Dan Rotigel wrote:Are you sure the motor cannot be serviced? A decent electric shop would have bearings/brushes and could re-wrap it. For 350 bucks you'd think it could be re-furbd. Alternatively, perhaps the pump is used in more mundane machines and available through a third party retailer. Just some thoughts.

Just re-read your post; what does the motor's sticker say on it? Zecchini?


cheers,
dan r.

Dan, the motor is a Zecchini. The guy who sold this machine to me has agreed to reimburse me for a new motor and pump. I think that even if the motor and pump are operational right now, I will get the new ones. This will prevent the "it just stopped working" two weeks into use problem. I am going to switch to a non-water cooled motor so some internal replumbing will be required but it will be more simple to work on and maintain.

More fun!

Thanks for the feedback.

C.

Friday evening update:

Finally, the machine is operational. Nothing was ever really wrong it other than a couple of very well hidden wires were disconnected which prevented the pump motor from running.

Everything is put back together and I have been doing some baseline testing. I noticed a small leak on the screw end of the stainless steel pipe that supplies water to the heat exchanger. There is a valve between the supply and this pipe that has a stub leading into the drain. I believe maybe it is either backflow prevention or some kind of pressure relief?

To the point. Something is awry with the connection between the stainless pipe and the valve. It is a compression pipe fitting like all the other stainless pipes on these machines. This pipe is going to be difficult to track down and more importantly, it will delay my gratification at least another week. What I am wondering is if perhaps this stainless steel pipe could be temporarily replaced with some kind of plumbing pipe? Maybe a flexible braided pipe? Can anyone see any kind of hazard with this?

The pipe in question can be seen below. It is protruding from the lower left side of the boiler and then doubling back underneathe the boiler:



Thanks for any help with this,

Chris

That little stub is probably an OPV (over pressure valve). Rotary pumps have a built in pressure release but if for some reason it malfunctions or you have the pressure ramped up way too high, a little valve opens to vent the excess pump pressure.

As you describe it, that line is on the pressurized side of the pump. I doubt a flex line could contain the pressure. It would probably burst around the flex joint. You could order the bullet ends from am espresso parts dealer and solder them onto some copper and bend your own tube.

Glad the machine is coming together for you. There is nothing more satisfying than rebuilding/reconditioning a machine with you own two hands.

Thanks for the support!

You are correct. It is the pressurized side of the pump. I pulled the pipe off and inspected. There is a hairline crack just on the inside of that nipple. It is covered by the bolt when the pipe is attached which is why it appears to be leaking out of the bolt. I wonder if some plumbing solder or maybe some JB Weld would be a viable alternative (even if just temporary?).

Some braided flexible hoses can hold the pressure, although I don't know if they all can. The outlet side of the vibe pump on my Faema 1-group is to a braided hose.

Also, JB Weld (or JB Water Weld) will work.

CMA ended up having the part (fortunately since the design has changed thereby eliminating this pipe). It came in last night and the journey began.

Some initial observations:

- Rotary pumps are quite
- This machine has an endless supply of steam. It never goes away. And it sprays milk farther than any other machine I have used.
- The hot water arm is too big. I am going to replace it with one of those short arms.
- Plumbed in machines are a no-brainer. If you are on the fence.... leap.
- Adjusting pressure and temp are very simple... and make for interesting analysis
- The shower screen is much deeper than on the Silvia

More comments to follow.

Next steps: Aesthetics.

Upcoming steps: PID, pre-infusion delay.


C.

PaulTheRoaster wrote:Some braided flexible hoses can hold the pressure, although I don't know if they all can. The outlet side of the vibe pump on my Faema 1-group is to a braided hose.

Also, JB Weld (or JB Water Weld) will work.

I was actually thinking about the stiff flex hose. The rubber hose with the stainless braid will hold the pressure. My two group uses the SS braided hose for the pump input and output to the copper lines. I misunderstood which type of pipe you were referring to.

Glad to see you found the OEM pipe and got it working. I must agree with you initial statements, a rotary pump along with inbound and outbound plumbing is wonderful. I will never go back to a drip tray and pourover, or anything smaller than a 3L boiler.

Congratulations on the accomplishment. It is a wonderful feeling isn't it.

A few weeks have gone by since bringing the machine home. I have been contemplating what I could do to improve the aesthetics of this machine. I think the answer is: nearly anything. I saw some pictures of Paul Pratt's P1 machine with the (polycarbonate?) panels and thought about putting together an either translucent or even transparent paneling system in conjunction with the existing stainless panels. The plastic-ish type materials would be interesting because they could be easily cut and then glued together to fabricate shapes at home. Metalwork would have to be done at a shop. I am definitely going to replace the legs. I can actually get the machine down to kitchen counter top height with these mods. The plastic panels will make it easier to build a box for the PID and temp controls.

I am also working out what electronic mods. Ken's PIDing his HX makes sense to me. I will have a custom thermocouple made either by Omega or by myself to fit into the only port available - the pressurestat tube (once removed). I also want to add a thermocouple in the group water path via a large bored bolt on top of my group just about the giculeur. I am thinking of making that one myself. I want to hook the group t/c up to a single purpose temp monitor that just displays the temperature. It seem difficult to find something like this. The housing for the PID and the temp monitor needs to be aesthetically pleasing and mounting them in the same box will make it attractive as well as make it easier to hook up a datalogger through some interface later on.

A couple of questions:

1. Is there any downside to making your own thermocouples?
2. I have read a gazillion posts related to the topic but can only conclude that there must be some longevity benefits from having one manufactured?
3. Does anyone know of some kind of flat LCD or LED thermocouple thermometer that could be used in this case?
4. Would a T type t/c be the best bet? Is there a downside to a T type?

Thanks,

Chris