EM6910 collar replacement - Abort, Abort!

[jazrotorman]

Replaced my brewhead seal two weeks ago.
Was running great, no leaks when all of a sudden: Leaks!

I ordered a new collar but then checked the seal and it has a gouge out of it. Not sure if the gouge is enough to let water through, but suspect it is and I should have just ordered another seal instead.



Thought I may as well replace the collar since it arrived this morning. Followed Wan's excellent guide but came unstuck when attempting to remove the Torx screws holding the collar. They all snapped on me!

At that point, I thought about drilling them out or buying a screw extractor, but realised I didnt have any replacement screws on hand, and the underlying feeling that I would go to a lot of effort to replace the collar, only to have it still leak due to the seal.

For now, I have tried to fill the gap in the seal to see if it is that, but suspect it wont hold until I get another seal.

I hope I don't have to buy a new seal every second week!

I find it quite hard to line up the portafilter handle. Often takes a few goes (seems to want to default to sitting at a 30 degree angle) until it is sitting flat and can be rotated into place. Does anyone else have that issue or have any tricks to help properly align it?

This is probably why there is now a chunk out of the brewhead seal. Guess I need to get another one and be very patient when trying to line up the portafilter handle.

[Xanthine]

I find it quite hard to line up the portafilter handle. Often takes a few goes (seems to want to default to sitting at a 30 degree angle) until it is sitting flat and can be rotated into place.

The group handle should go into place easily. I looked at a friend's machine recently which had a similar problem. It turned out that the group collar had lipped badly to the extent that it was jambing the sides of the portafilter when you tried to install it (similar to, but worse than, this).



He was able to carefully file the lips away so that it would fit again. In his case the lipping was only at the start of the ramps in the collar and his handle would only turn a little way before becoming tight. We pulled the seal out and found that there was a considerable build-up of scale under it like this one which has been scraped loose -



He packed the recess of his with paper towel soaked in vinegar to soften it before scraping it out. I just scraped this one with a broken piece of wooden chopstick then used a stainless steel scourer in it. Both sealed perfectly afterwards although the one in the photo above let the group handle turn past 90deg because of the collar wear.

It is possible that the collar lip was responsible for the chunk out of your seal but it would pay to check the rim of your group handle and basket for any roughness. The other possibility is that the seal had welded itself to the group handle after being left in place for too long.

Hope this helps
Trev

[TampIt]

Replaced my brewhead seal two weeks ago.
Was running great, no leaks when all of a sudden: Leaks!

I ordered a new collar but then checked the seal and it has a gouge out of it. Not sure if the gouge is enough to let water through, but suspect it is and I should have just ordered another seal instead.

[ATTACH=CONFIG]10145[/ATTACH]

Thought I may as well replace the collar since it arrived this morning. Followed Wan's excellent guide but came unstuck when attempting to remove the Torx screws holding the collar. They all snapped on me!

At that point, I thought about drilling them out or buying a screw extractor, but realised I didnt have any replacement screws on hand, and the underlying feeling that I would go to a lot of effort to replace the collar, only to have it still leak due to the seal.

For now, I have tried to fill the gap in the seal to see if it is that, but suspect it wont hold until I get another seal.

I hope I don't have to buy a new seal every second week!

I find it quite hard to line up the portafilter handle. Often takes a few goes (seems to want to default to sitting at a 30 degree angle) until it is sitting flat and can be rotated into place. Does anyone else have that issue or have any tricks to help properly align it?

This is probably why there is now a chunk out of the brewhead seal. Guess I need to get another one and be very patient when trying to line up the portafilter handle.

[ATTACH=CONFIG]10146[/ATTACH][ATTACH=CONFIG]10147[/ATTACH][ATTACH=CONFIG]10148[/ATTACH]

Hi jazrotorman

1) The "big white chunk" is a worry, however the inner ring of the seal is the first line of defence. Yours looks like the inner showersceen was mismounted and tore it (would need a photo at a better angle to be sure, but 1/2 inch both left & right from the white bit in your photo). Been there, done that so if you also managed it don't feel too bad. Nowadays I always run my fingers around the whole seal to make sure the first showerscreen is properly located. Ditto the second showerscreen. Sure makes the p/f hard to turn, doesn't it? I even managed to bend my showerscreen in the process (... unprintable self directed curses ...) whilst stuffing up the height for the p/f.
2) I am scrupulous in keeping all coffee grounds out of the seal area (all machines, not just my 6910 / 7000) as otherwise it forms a grinding paste and destroys things.
3) IF you ever decide to pull a collar off again, try a little Penetrene for at least a day or two first. It just slowly soaks in, removing corrosion and freeing such parts up. So much easier than stripping heads off.

I agree with Trev - give the whole area an A to Z clean and then check for wear and jagged edges. After working out the 6910's quirks, I am still on the same seal (three+ years). Ditto my 2 group La Pav - the first one went twenty years without needing a new seal, however it had never had a coffee ground in the critical space since new.

Hope this helps

TampIt

[jazrotorman]

Thanks a lot for your replies Xanthine and TampIt.

Sure enough, there is a small tear on the inner part of the seal where the shower screen goes in.

Thankfully, the company I ordered the seal though last time, but failed to deliver, should still have it in stock. Hoping I can pick it up tomorrow - the sooner I get another one the better, missing the nice coffee that this machine makes.

I have felt the collar and don't feel anything too jaggered. I suspect when I put the portafilter in, I probably tried twisting it in when it was not sitting perfectly level. I guess I just need to take more care.

[jazrotorman]

So close...



Off to buy a screw extractor tonight. Tried giving it a gentle hit with a screwdriver and hammer (after soaking in some CRC for half an hour) and after a while was able to loosen it as per the gap in the photo. It is very stubborn and wants to fight. Looking forward to getting the new collar in so I can get back to some good coffee!

[rawill]

If you haven't got the extractors go for the square ones, they are tapered, have 4 real hardened edges, you drill a hole, tap them in, they are magic, come in a set.
Much better than any other easyouts I have used, often they just burr off the edge, and sometimes break off making the job even worse.

[noidle22]

You don't really need to extract the broken screws as long as the heads have snapped cleanly off.

The thermoblock does not have any thread on it, the thread is in the collar itself. Seeing as you are replacing the collar, remove the thermoblock completely from the machine and then pry off the collar and the broken threaded sections should come away with it.

If you do this, be careful of the copper piping leading to the solenoid valve as the connection at the thermoblock can be a bit weak and the compression fitting there can sometimes snap.

If you want a new set of OEM screws, inbox me and I can post some to you.

[jazrotorman]

I managed to pick up one, but unfortunately the t bar that I bought kept slipping. In the end, I got a bit brutal with it and gave the old collar a whack with a hammer and screwdriver. After some time, it eventually came loose.
As per this photo, you can see the old loktite and the sheared off screws. You can also see the wear on the collar.
Have fitted the new collar and now the leaks are gone. Well, actually this morning it did leak but I think that was because I hadnt turned the portafilter handle enough. Need to be more forceful with it I think.

[jazrotorman]

Thanks noidle22, like you suggested, I used a screwdriver and pried it off (and gave it a head start with a few good hits of the hammer! Thanks for the offer of the OEM screws but I managed to pick some up (Not OEM ones but hopefully they will hold for a while).

[noidle22]

Good news. There's nothing special about the OEM screws really, they're just mild steel I think.

The ones you have used as long as they are long enough to thread a decent amount into the collar and you remembered to fit the spring washers should be fine.

[bryonvp]

Hi all,
I have just finished replacing the collar on my old 6910. New collar, and new group seal.
After successfully putting it all back together, I now find the portafilter is extremely tight - I can barely get it to lock into the collar. Way short of 6 o'clock position.
Any thoughts on what could be wrong? There were a couple of thin flat washers left over - were these supposed to go between the thermoblock and collar when reassembling? (there were only 2 - so I guess not)
Interestingly - the collar was damaged after the collar / portafilter became tight after my last seal replacement and it wore the collar out. I thought they were genuine seals - but maybe they are too thick?
Any help would be appreciated!

[Xanthine]

Have you tried cleaning the scale out of the seal groove as mentioned near the start of this thread?

Sorry, can't help with any suggestions for the washers.

[gordons]

Hi bryonvp,

I have just gone through the same exercise. The original collar was replaced under warranty and lasted 10 months. The second time I decided to replace myself. Have done so but now experience group head locking at 7 o'clock and also tight. I had replaced seal prior to replacing collar. As it was leaking coffee all over the place before replacing collar I will remove seal to check for coffee grounds buildup.

I also noticed 3 spacing shims on each collar screw. If there is no coffee buildup under seal then I guess I will need more shims. I don't know if the shims are normal as I haven't seen reference to them in other posts -even the excellent instruction to replace collar elsewhere in this forum- or perhaps it is a new feature! One thing for sure it gets real easy after disassembling several times!

My collar was warn substantially at the start of tightening group head. Elsewhere in forums this suggests I have been over filling baskets, so I will need to use less coffee and see.

Anyway I hope your problems have been sorted out and you are enjoying a good shot once more.