La Pavoni Europiccola grouphead bolt snapped - Help!

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john402052000
Posts: 151
Joined: 12 years ago

#1: Post by john402052000 »

Oh boy -- just started the rebuild on my premillenium Europiccola. When I went to unbolt the left group head bolt it snapped. Photo attached. Where can I get a replacement bolt and, more importantly, what's the best way to get the snapped off bolt out? Thanks in advance.

john402052000 (original poster)
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Joined: 12 years ago

#2: Post by john402052000 (original poster) »

Well the hits keep coming. Got the screen and piston out and discovered that the rod seal was broken. I guess I can get these the same place I can hopefully get the new bolt. Any advice on how to get the remaining piece of the seal out? Seems stuck in there pretty tight.

forbeskm
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Joined: 11 years ago

#3: Post by forbeskm »

For the threads, you look to have plenty left to get a grip on.

I would try penetrating oil being careful not to spray into the tank, cover the boiler hole. Then heat and vise grips. You can also try tightening just a bit before loosening, which sometimes works.

Otherwise you can try and easy out like I had to but mine was basically flush and you have something to work with.

Four or so Pavoni rebuild thread

john402052000 (original poster)
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#4: Post by john402052000 (original poster) »

Thanks! A couple quick questions:

1) I've got Gunk Liquid Wrench Super Penetrant. It's for freeing rusted bolts. Would that work?

2) How should I apply the heat?

ira
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#5: Post by ira »

Heat makes things expand, cold makes them shrink so in a perfect world you want to warm the housing and freeze the bolt and then try. Heat will also make some things softer which makes it easier to turn. I've heard lots of people swear by Kroil but the important part is patience, Warm the case with a heat gun or torch and then apply the penetrant and wait, warm and reapply a few time a day for a couple of days before trying and occasionally try moving it. Do not get the heat anywhere near enough to boil or burn the penetrant. Big ViceGrips are really handy for stuff like this. Don't turn it so hard you break it again.

And always remember, patience is your friend. You want to penetrant to soak all the way into the threads and that takes time.

Ira

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rpavlis
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#6: Post by rpavlis »

This is NOT a special bolt. (M6x1.0 threads, I believe) However, you should not put an ordinary steel one in it. Many of these have shorter bolts than the La Pavoni specifications. These gave the opposite problem on mine, the threads began to strip! If I remember correctly the specification is for 14mm length. You can measure the depth of the bore and put a longer one in. Soaking with various oils to help remove bolts will likely help. Heating with an heat gun once oil has been applied and allowed to stand for a long time may help.

It is surprising that this bolt ever had a chance to get into that condition because the group tends to need frequent disassembly to avoid having it be filled with nasty things, and to replace seals which give out from time to time.

If all else fail, the bolt could be drilled out, preferably with a left handed drill bit. It would need to be chucked very very well, and the drilling would need to be done with great care, because the surrounding material is brass.

You may have to run an M6x0.75 tap down the bore to clean the threads. Make sure that the threads are in good shape. Should you find them in bad condition, you should probably get a piece of M6x0.75 threaded rod and cut a piece to be long enough to go to the bottom of the bore, and then put a decorative acorn nut on it. (If you should fail to be able to find M6x0.75 threaded rod, you can decapitate a long enough M6x0.75 bolt.)

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crazy4espresso
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#7: Post by crazy4espresso »

Inside the group you've got a broken c-clip. You should be able to remove that easily with a pick tool. Underneath is a brass ring, then the seal.
I've encountered badly rusted c-clips that have been a pain to remove. Fortunately that's not the case with yours.
"I would rather suffer with coffee than be senseless." — Napoleon Bonaparte
LMWDP #427

john402052000 (original poster)
Posts: 151
Joined: 12 years ago

#8: Post by john402052000 (original poster) »

I was able to get the clip out. It also looks like I can order a replacement bolt from Stephano's and a new clip set from OE.

Regarding the bolt -- since I won't have the parts to rebuild for a while I'll plan on setting the unit on its back and putting a few drops of the Gunk at the base of the broken screw and leaving it a few days. I'll see if I can borrow a heat gun from someone.

I'm not handy enough to want to try and tap the bolt out if it shears at the boiler face, so if that happens I may take it to a machine shop, or some other place that has the skill to get the part out.

Here's the front and back of the stuff I've got. Smells like WD 40 or 3 in 1 oil to me.

thanks!



ira
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#9: Post by ira »

A hair dryer will help to warm it up as will an air popcorn popper or even a candle if you pay attention.

Ira

ira
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#10: Post by ira »

ira wrote:A hair dryer will help to warm it up as will an air popcorn popper or even a candle if you pay attention. Sometimes I'll even turn on the over to 250F, let it warm up completely, turn it off and then put in something to warm. Turning it off insures it will not get hot spots and hurt what you put in. You'll have to air it out if it has the oil on it though.

Ira

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