EM6910 Collar Replacement. A How To Guide

[Xanthine]

Following this guide is a good way to snap the nipple at the back of the thermoblock connecting the solenoid valve to the thermoblock.

It seems like you just have to look at this pipe the wrong way and it snaps off. I have just managed to break one in the course of replacing a 3way solenoid. Normally this would require a replacement of the brew thermoblock which is both expensive and time consuming but with a bit of thought and quite a bit of time I have managed to make a repair.
Fortunately the break to the pipe always seems to be right at the brass olive leaving most of the pipe from the themoblock intact.

Here’s how I went about it -
The first thing was to remove the thermoblock and then press the olive off the broken pipe using the cap nut and the shank of a broken 4.5mm drill in the vice as a press.







The olive came off quite easily and then it and the cap nut were refitted to the stub protruding from the thermoblock after part of the adjacent screw mount had been cut away to allow the cap nut to be turned.








Before fitting the connecting pipe to the three-way the “u” needed to be carefully stretched to make up for the missing 10mm of pipe and the collar screw head adjacent was ground down so it could be correctly fitted.







BTW, the 3 way failure was caused by a crack in the brass tube containing the plunger. This caused leakage into the coil which burnt out and leaked current to earth and kept tripping the breaker.

[Karyn]

Dredging up an old post but I also would like to know the answer to this!

We ended up contacting a local repairer. They sent us some of the stuff they use, so not sure of brand but they said it should go in the collar, where it makes contact with the filter handle when you put it in.

[level3ninja]

If anyone is looking for a working link it's available in the documentation section: https://coffeesnobs.com.au/forum/equ...lacement-guide

[scottwright]

Hi, it mentions needing food grade grease in the tutorial but doesnt mention where its used?. Also, what type grease is best?. Thanks for any help.

Dredging up an old post but I also would like to know the answer to this!

[Shortie]

How did the second collar replacement work out?
Do you have any tips to offer?
I'm getting by with a new seal & home-made packing washers; will need to eventually replace collar. Thanks.

[Karyn]

Hi, it mentions needing food grade grease in the tutorial but doesnt mention where its used?. Also, what type grease is best?. Thanks for any help.

[LeroyC]

I have just replaced the collar in my Em6910, using (what I assume are) the original instructions. Care and time are mandatory, but the job was a success. The handle now locks positively, zero leakage.

When disassembling, I was somewhat surprised to find that the collar screws were quite loose. I wondered, for a moment, if just tightening them might have saved a replacement. But obviously, as I had bought the collar, I pushed ahead

Anyway, encouraged by the successful restoration, I treated myself to a new M2M stepless grinder. Happy Days!

They’re all like that. Tightening them doesn’t make any difference.

[prh]

I have just replaced the collar in my Em6910, using (what I assume are) the original instructions. Care and time are mandatory, but the job was a success. The handle now locks positively, zero leakage.

When disassembling, I was somewhat surprised to find that the collar screws were quite loose. I wondered, for a moment, if just tightening them might have saved a replacement. But obviously, as I had bought the collar, I pushed ahead

Anyway, encouraged by the successful restoration, I treated myself to a new M2M stepless grinder. Happy Days!

[Peteski79]

anyone know if this guide is suitable for the em7000?
Thanks.

[HomeBrew]

This guide is missing some steps that I would like to have seen. Following this guide is a good way to snap the nipple at the back of the thermoblock connecting the solenoid valve to the thermoblock.
It makes it quicker in some ways but in the long run, it's far riskier. I'm in the slow process of compiling another guide. It will take longer but is far safer and much less stressful. ...

I know it a good 3 ½ years since this post, so I'm guessing the updated guide stalled and got overtaken by other priorities.

I'm at the stage of having to replace my collar again. I was not overly comfortable with the removal step in the current guide and be more than happy to spend more time to remove the thermoblock (if that is all that is required). I notice that LeroyC made a similar comment further on.

Do either of you (noidle22, LeroyC or anyone else that has done this/ese extra step(s)) have the time to give at least an overview of the additional work. I'd be happy to document the steps for future repairers.

Thanks.

[doniuv]

Sweet, thanks I'll go with that. I have tried to pack the seal with some gasket paper but that was not enough. I put 2 layers in and figured I don't want to have half a seal sitting in the housing and start folding the shower plates backwards. It's looking like the collar as thats the last item that will influence the locking in and upward pressure onto the seal. Appreciate the pointers thanks

[TampIt]

Just read through the doco, really impressed with the attention to detail. I am figuring that the collar is the part I have to change as I have tried changing out the seal and that made no difference. It seems that the collar is "key" in getting upward pressure on the basket against the seal. The collar must be made out of some cheap metal as there doesn't seem to be much wear on the lobes on my basket. Many thanks for passing this on.

G'day doniuv

My starting point:-

Try either seal with a spacer between the top of the seal and the collar. It is a standard SB part, however you can easily make one yourself.

Most 6910s I encounter just need a thorough clean + a spacer. Replacing the collar is overkill - unless the previous owner got coffee grinds everywhere and then the grounds act like grinding paste and destroy the collar.

TampIt

[LeroyC]

Just read through the doco, really impressed with the attention to detail. I am figuring that the collar is the part I have to change as I have tried changing out the seal and that made no difference. It seems that the collar is "key" in getting upward pressure on the basket against the seal. The collar must be made out of some cheap metal as there doesn't seem to be much wear on the lobes on my basket. Many thanks for passing this on.

This guide was what got me started on refurbishing EM6910s. I’ve since done about 5 of them and while I still think the guide is a good starting point I disagree with how they suggest getting the collar out without removing the brew thermoblock. While it does involve removing a few more parts to get the thermoblock out it makes the job much easier overall and gives you an opportunity to clean out any coffee that’s in there at the same time. Just make sure you either take photos or make notes as you disassemble the machine so you know how to put it back together again. The only tricky bit is undoing (and reattaching) the brass nut that connects to the 3-way solenoid, but you just have to take your time and go easy.

[doniuv]

Just read through the doco, really impressed with the attention to detail. I am figuring that the collar is the part I have to change as I have tried changing out the seal and that made no difference. It seems that the collar is "key" in getting upward pressure on the basket against the seal. The collar must be made out of some cheap metal as there doesn't seem to be much wear on the lobes on my basket. Many thanks for passing this on.

[noidle22]

Part number is EM6910106.

The revised EM6900 collar will still work fine, you just need different bolts to attach the collar to the thermoblock as they used a smaller thread.