Weird La Pavoni Professional Leak

[faberic]

Hello,

I've bought myself a 2nd hand La Pavoni Professional (Pre-Millenium), but it has a weird leak.

When has almost heated up, at the point that the pressure is rising, water starts leaking from here:

(where the drops are shown). When I pull up the lever during this leak, the water starts leaking in a rapid rate, but after i've filled a cup with water by pulling the lever to is highest point, the leaking stops and it won't start again when the lever is down again. After that, the pressure reaches his normal point and I can make espresso without any problems.

Sometimes I can prevent the leaking by filling a cup with water before the leaking has begun yet, but this should be done at the right moment before the leaking. There are even times when the leaking stays away.

The problem is that the grouphead gets incredibly hot during this whole leaking thing, so the espresso is brewed too hot most of the time. At times when it does not leak, there is no problem with the temperature.

I think it has something to do with wrong pressures at wrong places at wrong times. Does anyone recognise this problem? When I've stopped the leak by pulling the lever up and down, there is a powerful downwards pressure from the lever when I try to pull it up again. This pressure seems to prevent the leaking.

Can anyone help me? Any suggestions are welcome!

Cheers,

Eric

[mayhew]

Not so weird. There is a gasket at the top there, along with a c-clip. The gasket is leaking.

The thing to do is order a piston rebuild kit for your machine. You're going to have to do all the work involved in replacing the pistons, might as well do them all. It's a pretty easy repair and well documented (me like picture!) here. The minor hassle will be removing the c-clip for which (in this case) you're going to need a specific tool. They're fairly cheap (got mine for $7).

[TUS172]

Excerpt:

Not so weird. There is a gasket at the top there, along with a c-clip. The gasket is leaking. The thing to do is order a piston rebuild kit for your machine. You're going to have to do all the work involved in replacing the pistons, might as well do them all.

Agreed... Here is a site and diagram that you can look at to order the kit from.
http://partsguru.com/LaPavoniHome...ers.html#Diagram-2

[faberic]

So this should do the trick: http://www.shop.partsguru.com/product.sc?productId=336.

But what tools do I need to disassemble the group head? It looks quite solid.

[Jarno]

Yes, it's the clear gasket on the right that's the culprit. It is a V-gasket When you remove it, note the orientation of which way the gasket is facing.

Let's see. Other things:

1. The bolts attaching the head to the boiler are metric.
2. The e-clips attaching the lever to the piston rod, I believe, are 13 mm. There is not a e-clip tool that size. I used a flat-blade screwdriver against the edges of the ring to partially push the clip off, then a pair of pliers to pull it off. (if the clip flies off, watch where it lands )
3. Another challenge is the removing of the filter screen. It is held/wedged in place by another gasket. I've read where some pry the gasket out with a screwdriver but had concerns with resulting scratches on the head. Another used a rubber mallet against the piston rod, forcing the screen off the head. This didn't work for me. What I do is this. I bring the machine to operating temperature, then shut it off. I then use a bowl of cold (must be cold) water and submerge the bottom of the group in it. Then I pump the lever up and down vigorously which draws cold water in and out of the brew chamber. I don't raise the lever high enough to allow brew/hot water to enter. Somehow this loosens the gasket and allows it to fall enough to pry out easily with a screwdriver. I don't know if this trick works predictably, but it worked with mine. Good luck.

[mayhew]

Info with pictures here:
http://www.home-barista.com/lever-espresso-machines/refeathering-peacock-pavoni-head-gasket-replacement-t70.html

and, as always
http://www.pavoniexpress.com

[mrgnomer]

No precision equipment is really needed to take apart a lever, I find. Trick is not to damage the chrome of on the bolts and such. You can use an adjustable wrench if you want. Wrap the bolt in tape to protect it.

As far as circlips go, a circlip tool will remove any clip regardless of it's size from what I've found. If the circlip isn't spring steel, like the circlips on my Cremina, you'll stretch them by removing them and replacing them means squeezing them back into the lever pin grooves with a pair of pliers. Again, the only thing I've had to watch out for is damaging the group's chrome by scratching it with a sharp pair of pliers.

Pulling out the gasket/showerscreen involves the same considerations. Snaking a bent paper clip behind the gasket to pull it out might work. Whatever you do you just have to be careful to not damage the gasket by gouging it.

Replacing the piston into the cylinder also requires some consideration of the seals. With the plastic lined cylinder of the newer LaPavoni's it's probably not as important but you don't want to damage the rubber seals by trying to force the piston back in. The lip of the cylinder could cut the piston seals if you don't compress them when sliding them back in. A good lube like Dow 111 helps.

Unbolting the whole group is the easiest way I've found to work on it.

[ccfore]

Just a heads up if you are going to be placing an order with Parts Guru. I ordered a couple parts on April 6th and have not received them or heard anything besides the initial email response after a couple emails. People have had good luck with them in the past and maybe they are waiting on a part, I don't know as this is my first order with them.
I guess I'll give them a call. Just thought I'd let you know in case you were in a hurry.

[faberic]

Before ordering anything, I thought it would be helpful to dissassemble the whole. And guess what, the spring clip that is supposed to hold the top gasket in place just wasn't there. In the refeathering article I read that this clip tends to rust out. So it can disappear, can't it?

The gasket doesn't look quite good though, so I'm thinking of ordering this: La Pavoni Service Kit.
To replace the gaskets and the C-clip.
Has anyone experience with espressoservices?

Cheers,

Eric

[faberic]

I fixed it, what an amazing difference!