Caravel group leaking

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
pacificmanitou
Posts: 1302
Joined: 12 years ago

#1: Post by pacificmanitou »

I recently acquired a caravel, and replaced the seals with ones from OE. however, the group still drips and the small o-ring in the piston is shorter than the recessed hole it goes in. Is that normal? How do I stop the leakage? I'd like to use my caravel for more than a decoration.
LMWDP #366

User avatar
peacecup
Posts: 3649
Joined: 19 years ago

#2: Post by peacecup »

I ended up going back to the original seals. You could try that if you still have them. KurtAugust has posted that he has come custom-made Caravel seals for sale on the B/S forum.

One thing I did was to keep water in the boiler at all times, including overnight, and whenever you're not using it. Put a container big enough to hold all of the water under the group, then fill it part way. Just keep refilling it, and after a while the leaks in mine stopped completely. It sometimes dripped while it was heating, but after a while even that stopped.

With a little patience most have gotten this problem figured out. It should be worth the effort.

PC
LMWDP #049
Hand-ground, hand-pulled: "hands down.."

pacificmanitou (original poster)
Posts: 1302
Joined: 12 years ago

#3: Post by pacificmanitou (original poster) »

I'm glad Im not the only one who has had a caravel go drip till the boiler is empty. I saw Kurt's custom seals, if this keeps up, I'll have to spring for those. It's strange, because the seals work perfectly for making espresso, and the taste is wonderful. It's just when the piston sits idle that it turns into a sieve.
LMWDP #366

User avatar
grog
Posts: 1807
Joined: 12 years ago

#4: Post by grog »

I've got the same issue. I may try Peacecup's solution - I know that on my Export, I had a base to boiler gasket that took a few days to completely seal. Hopefully it will work on the Caravel, too. Pacifocmanitou, as you point out, happily the leak doesn't impact the action of pulling shots. Mostly it's just annoying to have to manage the boiler leaking when it isn't in use. I've even tried leaving the portafilter and basket in place with spent puck and all, and all it does is make the leak slightly slower. Water still gets through.
LMWDP #514

pacificmanitou (original poster)
Posts: 1302
Joined: 12 years ago

#5: Post by pacificmanitou (original poster) »

Yeah it seems we've got the same issue. Once it's up to temp does your quit dripping?
LMWDP #366

User avatar
sorrentinacoffee
Posts: 747
Joined: 16 years ago

#6: Post by sorrentinacoffee »

I would say the leak does not affect shot pulling because the leak is caused by the small o-ring in the piston- not the piston seals. Have a look at your local hardware- chances are they have a selection of small o-rings and one of them fits well. If you find one that is slightly too large you can sand it down a little with fine sandpaper.

pacificmanitou (original poster)
Posts: 1302
Joined: 12 years ago

#7: Post by pacificmanitou (original poster) »

Another anomolie: if the kettle is more than half full, water comes out the top of the group on the upstroke. Is that also attributed to the o-ring? Also concerning the o-ring, I can't seem to figure out why it exists rather than a solid piston. Is there intentonal flow through the piston at any point? More specifically: would plugging the hole hurt anything?
LMWDP #366

Seacoffee
Posts: 338
Joined: 12 years ago

#8: Post by Seacoffee »

It breaks the vacuum and also allows the air to escape when the cylinder is filling with water on the upstroke then closes on the downstroke. A number of designs use a similar principle i.e. faema faemina.If you continue to hold on the upstroke with a filled boiler then water will flow out the top of the group and exit where the handle locks in.

The original Vam does not have the O ring and is a solid piston as you suggest.

User avatar
grog
Posts: 1807
Joined: 12 years ago

#9: Post by grog »

Interesting. I topped up the boiler yesterday afternoon after pulling a shot, and placed a bowl under the group to catch the anticipated draining water...and this morning, the bowl is still nearly empty. In the past the entire boiler has drained out overnight. Maybe the o-ring has finally resealed itself. Peacecup, thanks for the reminder that sometimes these seals just need time to settle in, basically.
LMWDP #514

pacificmanitou (original poster)
Posts: 1302
Joined: 12 years ago

#10: Post by pacificmanitou (original poster) »

I did the same, and while there was water in mine, there was less than before. I did have it on all day, I'm not sure if that helped or did anything at all.
LMWDP #366

Post Reply