I own an Izzo Duetto MK4. Bought back in 2014. I have serviced it a few times and has been a great learning tool. Recently I noticed that the coffee seemed weak and a cursory look at the brew pressure gauge identified a low pressure of around 4 bar. I also noticed the backflush was weak. So I stripped the e61 down and lubricated ( molykote). the backflush problem was instantly cured but the pressure remained low. I decided to adjust the brew pressure screw and after reaching the maximum adjustment I now have 9 or so bar pressure but more importantly great coffee again. Although it would appear there is no problem now I suspect myself the OPV is playing up as why do I need to adjust to maximum the brew pressure? Compensating for a leaky OPV maybe? I have phoned BB and spoke to a technician who said the OPV has nothing to do with it. if the pressure is low then the pump is at fault. I am sceptical. My question is: Can a faulty OPV cause low pressure? If that is the case where is the water going to? as there is none coming out of the little tube by the tray. The machine is plumbed in. How difficult is it to change an OPV on the izzo? Where can I find the part if I need to? Is it maybe the pump? What symptom’s should I look for? I should point out that about a year ago I cleaned the OPV as water was constantly coming out of the little tube by the front tray. That rectified the fault at the time. Don’t get me wrong the coffee extraction is perfect but I feel with the brew adjustment on maximum is not right.

coffeealex 1 Can a faulty OPV cause low pressure? 2 If that is the case where is the water going to? as there is none coming out of the little tube by the tray. The machine is plumbed in. 3. How difficult is it to change an OPV on the izzo? 4. Where can I find the part if I need to? 5. Is it maybe the pump? 6. What symptom’s should I look for? It can. It would be being returned to the tank (in quantity) via the tube from the Expansion valve (OPV). Have a look and see if this is happening when pulling a shot against a blind filter. If it’s not, discount the expansion valve. It’s easy Bella Barista or most internet espresso machine spares retailer, the part is quite generic. Remember this part is only to vent excess hydraulic water pressure due to water expansion on heating. It has no part in brew pressure regulation as in a vibration pump machine. It’s unlikely to be the cause of your problems (as you have described them) Yes, most likely The things to watch for are each symptoms cause stated in order of probability: the brew pressure needle showing back and forth variations, e.g. from 5 bar to 9 bar or 7 bar to 9 bar etc.. (balanced bypass playing up, seizing pump, failing capacitor) funny noises (pump seizing up, balanced bypass) the motor sometimes failing to start (capacitor) Pump struggles to make pressure (damaged/worn vanes, motor capacitor) Make a good quality video (with sound) of a shot pulled against a blind filter, upload to YouTube and link to it here. Show the brew pressure gauge

Thank you for your answer. I have uploaded the video. As previously mentioned it does reach pressure ok but the brew pressure setting is at maximum. The guy at BB said at the time that in his opinion the valve was stuck and that by turning the screwhead i freed it and so the pressure went up and is now ok. Does not explain why I needed to turn it so much to get it back up again. Excuse my ignorance in this.

coffeealex was the motor/pump always that noisy? Can you show a photo of your pump and what you adjusted. Look at the weep hole in the pump connection to the motor, has water been coming out?

I have posted a few pics. The screwhead (acorn shape) is shape is what I adjusted clockwise. I think the weep hole is that pipe and it looks dry. The noise has changed. It was more like a wow wow sound before and the case made a vibration sound. Now the vibration from the case has gone and thinking about it it does seem a bit louder.

Another pic from top. Also had a look at water tank to see if water is going back to it and it is bone dry. The green stuff on top of the brew boiler I am assuming is a previous leak to maybe when I replaced the temperature probe as although it looks green it is dry .

Well a few things…that tube is a waste of time….it does nothing to protect the motor bearings. I wrote this article after the MK1 Duetto was launched. You may well need to inspect yours…torch and spanner required. http://coffeetime.wikidot.com/duetto-pump-checks-and-home-made-leake-detector you should take a video with the top off and the camera on the pump…shot against a blind filter…oh you can leave the pump running for more than 3 seconds after the pressure maxes. The machine needs a serious clean in side and the bottom below all the components and boilers. A clean machine allows you to see problems faster then if it’s still leaking, fix the leaks, esp on top of the brew boiler. What water are you running? Have you owned it from new, or did you buy it used? What does your servicing entail, what have you replaced? Take a photo from the top at a greater distance, we might spot other problems for you.

Listened to your great advice and started to clean it. The water is coming through a bestmax premium filter Yes i have owned from new. Purchased in 2014 from BB replaced temp probe on brew boiler. Opened up OPV and cleaned after it was constantly losing water from tube into drip tray. Problem solved after cleaning inside of OPV. Have cleaned and lubricated cam on brew lever about 9 times. cleaned filter under brewhead and replaced later. Changed gasket seal under brewhead. Recently stripped all of e61 , top( mushroom) and bottom and cleaned as water was not backflushing with any force. Now it does after clean.

Looks much better, now you can see where leaks are coming from. I’d double check the hardness of your water. Pump or motor sounds noisy, split pump from motor and check for leaking.

Thank you Davec. I have never removed a pump before so can I check the procedure please. Make sure the machine is off and cold loosen 2 nuts: 13mm and 17mm loosen screw from collar underneath pump and lift body of pump upwards check underneath pump and in well for signs of water leakage. Is the above right? Thanks I have found this link which seems to explain which nuts to loosen : https://clivecoffee.zendesk.com/hc/en-us/articles/360001221713-Izzo-Duetto-Pump-Replacement The more I think about it the more I don’t think the pump was ever this noisy, so I am starting to think along reason 4 you mentioned earlier DavecUK Pump struggles to make pressure (damaged/worn vanes, motor capacitor) This is a great learning curve. I really appreciate you passing your knowledge on.

Oh well. I think its game over. I loosened off the pump and I think water has been going into the motor. Does that mean a new motor and pump would be needed? The odd thing is it works still ok? Is the loud noise coming from the motor rather than the pump? I am no expert and far from the inspirational knowledge of Dave C and others, but surely is that not a stupid design to put a pump over a motor that way or am I way too ignorant to see the merit?

Alex Izzo Duetto Mk4 low brew pressure

DavecUK

coffeealex Possibly it would briefly reduce the noise….but the bearing is shot…which may have damaged the bottom one as well due to vibration and runout. WD 40 isn’t bearing lubrication and shouldn’t be sprayed into factory sealed and grease lubricated races.

Just replace it. BB had 1 motor, I’d advise you get it, as a restock won’t be that price. I know what the factories in italy pay for those units.

P.S. I think it’s quite likely an Izzo Alex/Duetto motor.

coffeealex

DavecUK Thank you. I will give them another ring in the morning and give it a go. If i get stuck I will take it to them. Just quite eager not to admit defeat and end up letting BB do it. It will all depend on how its mounted at the bottom and whether it needs tapping or just hopefully a little bit of drilling. When i originally spoke to them they seemed to think it needed tapping. Im dubious but then what do i know? You get such satisfaction doing a job yourself and its a real pleasurable learning curve for me. If I had just a modicum of your knowledge base I would have a different mindset. So really appreciate all inputs on this forum . Best forum by a country mile!

coffeealex

DavecUK Ordered a new motor and pump yesterday from BB. You are totally right it would be folly to risk that they have none in stock as the price of the motor is very reasonable. I have also an agreement that if in the worst case scenario there is a compatibility problem they will take it back and refund. Therefore its a low risk move.

CoyoteOldMan

coffeealex When i originally spoke to them they seemed to think it needed tapping.

I’d be surprised if this were the case. Where are you based? Some people may be able to help with a tap tool or two…

Cuprajake

Why don’t you take the machine to them for repair and have a try if the ones in stock see what you think.

Then when yours is mended you can pick up you choice

coffeealex

Cuprajake Thanks for the suggestion. I had thought about that but a combination of the fact that I am stubborn and will not admit defeat easily, and also the fact they apparently would not be able to repair it while I wait as they could not guarantee the slot as they might get called away to a commercial job. Its also a pity Jordan is no longer there, he was a great technician and a great guy. TBH at the moment I just consider myself so lucky to be on such a forum, with many great helpful people like yourself, that whichever way my duetto ends up I am a lucky guy.

Cuprajake

I did mean leave it with them haha

coffeealex

CoyoteOldMan i’m in the Midlands

CoyoteOldMan

coffeealex Happy to travel to the “South” part of the Midlands (say as far North as Leicester/Birmingham) with a set of tools, if it helps!

coffeealex

CoyoteOldMan That’s really kind of you. I don’t want to put anyone out with their kind generosity. I may be able to travel down south to London as we sometimes go up there. Is it possible to Pm you and give you my phone number and maybe have a chat to work something out?

CoyoteOldMan

coffeealex I’m near Oxford, so it’s better than London traffic-wise (though you may not have any reason to go to/pass by Oxford to get to London if you are in Nottingham rather than anywhere on the M40 corridor), but we’ll manage something.

The forum has no PM facilities, unfortunately. If you want to ping me an email at the address in the signature, we’ll take it from there!

DavecUK

coffeealex I am also fairly sure it’s exactly the same motor as in your machine as I believe it has been in stock a very long time.

P.S. Do NOT spray WD shite or anything else into it’s bearings thinking the grease in them has dried up. It won’t have, and you will ruin the long term life of the motor. In fact the best thing you can do with the WD40 is give it to someone you don’t like.

CoyoteOldMan

DavecUK And suggest they spray it as an ‘extraction aid’ on their freshly tamped grounds.

coffeealex

Arrived quicker than I thought

DavecUK

coffeealex make sure the spring is in the inlet port… bit with cotton wool in it.

coffeealex

DavecUK

Would explain why there is cotton wool stuck in only one port. Is the spring that bit that you can see?

DavecUK

coffeealex Can’t see a spring. Perhaps they stopped using them? Part number 25. It acts as the bypass retainer.

https://www.fluidotech.it/site/assets/files/1300/co_50-200_rotary_vane_pump_spare_parts.pdf

How about a few more photos so I can see if it’s a Procon or FOT and the number. Who did you get the pump from.

coffeealex

DavecUK

Maybe, but then why put cotton wool in there. Might be worth me ringing BB to check if spec has changed. What is the spring supposed to do?

coffeealex

DavecUK For the little I know and looking at the Fluid O Tech website most have a spring although some like the 50-100 don’t. So as you say unless the site is not up to date and the spec has changed the 50- 200 should have a spring and one thing is for sure you have seen a lot more pumps than I have, so definitely guided by what you say. Thank you.

DavecUK

coffeealex

The balanced bypass valves opens under pressure to allow water to flow from outlet to inlet. The spring prevents the valve entering the inlet chamber.

It would be super great if you put up the photos I asked for so I’m not working blind.

P.S. the foam or in your case cotton wool stops crap getting into the pump, as per the installation manual and is removed just before connection.

coffeealex

DavecUK Sorry Dave. Just saw the bit about the photos. My bad. will do that now

DavecUK

coffeealex Remember, your old pump should have one in the inlet, if it’s original.

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