PRONTO ME717 – COMMON FAULT RESOLVED

This was the first Pronto machine I’ve met, but it’s reputation preceded it, so I knew what to expect. A mate in the industry asked me why I wanted to get involved with these machines and the best answer I can think of is that I want to keep some plastic out of the ocean.
Seriously these are not bad machines and many will end up in the landfill before their useful life is exceeded if somebody doesn’t stock parts and build up some expertise on them. So I’m doing it for the turtles.

This machine had an issue that is common with Saeco and Merol machines as well. The machine would boot up ok, run the rinse ok, but when it would come to making a coffee, it ran the grinder positioned the brew unit in the infusion position (attempted too) but did not stop and then continued cycling the brew unit and dumped the coffee grounds without attempting to make a shot of coffee.

The first thing I noticed was how coarse the coffee grounds were. So it was obvious that the volume of coffee was too great for the brew chamber. The larger the particles of coffee, the greater the volume of coffee in the brew chamber (more coffee grounds are produced in the allocated grind time). When the software detects too much current draw (or it may be detected by a switch in this machine) as a brew unit pushes down on a bulky mass of coffee, it can not get the brew unit to the brew position, so it rejects the coffee by returning the brew unit to the home position. So I set the coffee dose to the lowest setting and sure enough the machine went through and made a shot. Not a great one but it worked.

Now why, I noticed the adjustment knob was next too useless, so it was impossible to adjust the grind, but even more obvious, the blades were seriously blunt. This thing is going to chew not chop the coffee beans and it had only done 1625 cups. It looks like cheap metal. So the solution went as follows.

  1. Dismantle the grinder and replace the blades. yes I stock the Jura blades which fit perfectly.
  2. Calibrate the grinder with the adjustment mechanism removed. With the new blades and the grinder adjusted correctly I had good coffee and pucks again. And fantastic extraction, see the photo below. A little sloppy, but this was rectified when I selected a stronger dose. A new brew unit would probably rectify this. See pic of the pucks after new blades below.
  3. Lubed the brew unit, cleaned the filter and changed the main oring. Again I sell the merol service kits for doing this.

Now some people are also replacing the brew unit and it has been suggested that gears strip on this model. I opened up this machine and the gears were all ok. See photo.

Below are some pictures showing the various steps which may be helpful. Note you could probably have kept the old grinder blades but I don’t suggest that. It may also be necessary in some cases to replace the grinder.

I hope that helps and if you require parts I do not have listed. Please ask and I will order them with my next order. They make take time but I will get them. Think of the turtles before you dump these machines.

Coffee grounds too coarse.
removing the blunt old cheap blades
Removing the Grinder Adjustment Mec

Blades Remove from a Pronto Grinder
Old Blades Removed and New one Installed

Purchase Pronto Parts Here

Perfect Pucks after Changing the Blades and Calibrating
Gears all Ok, easy to access via LHS Panel.
Bloody Good Extraction with the New Blades. Even I would drink that.

Comments are closed.

%d bloggers like this: