# Newbie gaggia classic rebuild seized snapped screws



## Bagpu55 (Dec 23, 2019)

Hello. Bit of advice please. I have a new to me 2007 classic and I started to strip it down yesterday. Most of it came apart quite well apart from the boiler screws and the opv screws. Using combinations of penetrating fluid and heat gun I am currently left with 1 boiler screw Insitu and a snapped corroded opv screws (see pic).

When I use heat do heat the brass base or the screw/boiler area? Penetrating fluid has been on for a day now and it's still solid. Do I try to untighten when it's still hot? Don't want to snap this one off of I can help it.

On the opv snapped screws what's the best way to remove this. I can try mole grips but probably get 1 shot before that snaps off inside

I want a project I said ?. Appreciate any help. I have read what other posts I could find.


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## El carajillo (Mar 16, 2013)

Apply the heat to the bolt head, boiler flange and corner of the brew head (away from the heating element) Also directly to the OPV stud. You will need to apply plenty of heat as the brass / ally will absorb a lot of heat. You can apply some penetrating fluid while HOT (but do it outside it stinks). Then try working the bolt /stud GENTLY backwards and forwards, applying more fluid as you do. If still no movement wrap some small pieces of rag around bolt and stud spray with P/fluid and leave to soak overnight or longer, reapplying fluid occaisionaly.

If the worst happens they can be drilled out and retapped to the same size


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## L&R (Mar 8, 2018)

You need a powerful torch for the bolts, if you make them red, they will come off. I use а vise to grab the bolts afterwards.


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## ratty (Sep 22, 2019)

Put the directly opposite hex head bolt back in the boiler (with some lube) then follow the other's advice to remove the tight boiler bolt hex head.

If the hex has been rounded off on the bolt, try a small pair of stilsons on the body of the bolt head if they will fit in the available space.


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## Bagpu55 (Dec 23, 2019)

Great advice all. I will try the above and let you know. Fingers crossed. Thankyou


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## MartinB (May 8, 2011)

Smash a torx into the remaining boiler bolt, that should grip it and then remove it.

I've probably got a spare group head if you get stuck ?


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## El carajillo (Mar 16, 2013)

ratty said:


> Put the directly opposite hex head bolt back in the boiler (with some lube) then follow the other's advice to remove the tight boiler bolt hex head.
> 
> If the hex has been rounded off on the bolt, try a small pair of stilsons on the body of the bolt head if they will fit in the available space.


 I have a set of 24" stilsons, would these do you think  :classic_biggrin: OR you could beat it into submission


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## Bagpu55 (Dec 23, 2019)

MartinB said:


> Smash a torx into the remaining boiler bolt, that should grip it and then remove it.
> 
> I've probably got a spare group head if you get stuck ?


 Haha cheers will go with the light approach first before I open the bottom draw in the tool chest. Cheers for the offer


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## Cooffe (Mar 7, 2019)

Have you tried an impact driver or applying tension and hitting fairly hard with a hammer? You just need to crack it and it'll go.


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## Tag1260 (Jun 17, 2019)

I broke three out of the four boiler screws and to my surprise, when I went to remove the pieces, they came right out. Seems that they were stuck in the unthreaded side if the boiler. Hopefully yours are the same.


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## ratty (Sep 22, 2019)

When (or if!) you remove the offending bolt, try and find some Zinc plated bolts to replace them, rather than Stainless Steel. Stainless and Aluminium will be significantly more prone to galvanic corrosion between the two metals than Zinc and Aluminium and could quite quickly give you a similar problem again!


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## Bagpu55 (Dec 23, 2019)

Cooffe said:


> Have you tried an impact driver or applying tension and hitting fairly hard with a hammer? You just need to crack it and it'll go.


 Yes tried hitting it but not under torque will give that a go now.


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## Bagpu55 (Dec 23, 2019)

ratty said:


> When (or if!) you remove the offending bolt, try and find some Zinc plated bolts to replace them, rather than Stainless Steel. Stainless and Aluminium will be significantly more prone to galvanic corrosion between the two metals than Zinc and Aluminium and could quite quickly give you a similar problem again!


 Thats a really good point will do, I guess ebay?? Do you apply any anti seize compound also? Not seen if the holes go straight through.


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## Bagpu55 (Dec 23, 2019)

Right going to dig the heat gun out and warm these suckers up!!


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## Bagpu55 (Dec 23, 2019)

You beauty!!!! Right now for the snapped one!!!


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## L&R (Mar 8, 2018)

Looks normal inside, clean it well and replace 6pcs M6x16 and 4 pcs M5 with stainless steel ones.


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## Cooffe (Mar 7, 2019)

@Bagpu55 how did you get it out in the end?


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## Bagpu55 (Dec 23, 2019)

Cooffe said:


> @Bagpu55 how did you get it out in the end?


 Lots of patience and heat, spray, wiggle. Was not trying to be a right monkey on a spanner. Had to use my socket set with a decent allen attachment. A soon as it shifted slightly I used my screw driver attachment tighten/unwind so not to force it too much. Still stuck with one though ?


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## Bagpu55 (Dec 23, 2019)

Just stuck with the broken opv screw. It is stuck solid. Tried a load of heat (2000w heat gun best I have) and a lot of penetrating oil but won't budge. Getting hard to grip it now. Any other ideas for this one.


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## Tag1260 (Jun 17, 2019)

Can only say not near enough heat.


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## MartinB (May 8, 2011)

Freeze it?


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## ashcroc (Oct 28, 2016)

Bagpu55 said:


> Just stuck with the broken opv screw. It is stuck solid. Tried a load of heat (2000w heat gun best I have) and a lot of penetrating oil but won't budge. Getting hard to grip it now. Any other ideas for this one.
> <img alt="IMG_20200106_210402678.thumb.jpg.6942848a07760a2b912957197f3a5663.jpg" data-fileid="35158" data-src="<fileStore.core_Attachment>/monthly_2020_01/IMG_20200106_210402678.thumb.jpg.6942848a07760a2b912957197f3a5663.jpg" src="https://www.coffeeforums.co.uk/applications/core/interface/js/spacer.png">


Is there enough meat left to cut a slot in the end to fit a flat screwdriver?


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## ratty (Sep 22, 2019)

L&R said:


> Looks normal inside, clean it well and replace 6pcs M6x16 and 4 pcs M5 with stainless steel ones.


 As I said previously a bad choice using stainless steel bolts. There is a large potential difference between Stainless steel and aluminium which will cause galvanic corrosion.

Much less potential difference between zinc and aluminium, so it's much preferable to use zinc plated bolts,


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## Cooffe (Mar 7, 2019)

I'd say Mole grips and a butane torch should get that right out...


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## El carajillo (Mar 16, 2013)

After a couple of applications of heat, allow to completely cool. Stand on edge stud to top, build a small 'moat' with some putty / blu-tack/ similar, fill with P/fluid and leave to soak. A couple of days now could save you a lot of grief== drilling +tapping.


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## L&R (Mar 8, 2018)

ratty said:


> As I said previously a bad choice using stainless steel bolts. There is a large potential difference between Stainless steel and aluminium which will cause galvanic corrosion.
> 
> Much less potential difference between zinc and aluminium, so it's much preferable to use zinc plated bolts,


 I have changed lots of bolts on Classics, yesterday stripped down one of the refurbished machines(2y ago) for cleaning, bolts and all around them were like new.

BR


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## ratty (Sep 22, 2019)

L&R said:


> I have changed lots of bolts on Classics, yesterday stripped down one of the refurbished machines(2y ago) for cleaning, bolts and all around them were like new.
> 
> BR


 What can I say?

Seems like you've got me beat!

But being as you quoted me;

Ratty

20 years shop floor worker at SPS Technologies (Boltmaker)

HND Mechanical Engineering

BSc (Hons) Industrial Engineering (Manufacturing)

5 years post graduate engineering researcher at Coventry, Birmingham, Nottingham and Loughborough Universites.


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## L&R (Mar 8, 2018)

That is impressive but having seen lots of rusty(almost welded in alu boiler) cheap zink coated bolts in Classics I won't put anything different from A2 bolts in there.

I am a simple programmer though and coffee machines are just my hobby.


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## Bagpu55 (Dec 23, 2019)

El carajillo said:


> After a couple of applications of heat, allow to completely cool. Stand on edge stud to top, build a small 'moat' with some putty / blu-tack/ similar, fill with P/fluid and leave to soak. A couple of days now could save you a lot of grief== drilling +tapping.


 I think I will try this, will pick up a torch, give it a good heat and P fluid soak. Id rather get it out than having to drill and tap.


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## Bagpu55 (Dec 23, 2019)

L&R said:


> That is impressive but having seen lots of rusty(almost welded in alu boiler) cheap zink coated bolts in Classics I won't put anything different from A2 bolts in there.
> 
> I am a simple programmer though and coffee machines are just my hobby.


 Do people replace with bolts, rather than an allen headed screws? A spanner fitting has got to be better. In honesty once I get it sorted I would replace them regularly as part of a service. But the corrosion issue is nuisance.


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## Tag1260 (Jun 17, 2019)

Right or wrong I used some Never-Seize on mine.


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## El carajillo (Mar 16, 2013)

Replacing them with bolts can cause a problem due to the fact the bolt head is too close to the boiler to get a socket / ring spanner on some of them .


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## MartinB (May 8, 2011)

In dealing with many classics, I've never encountered a stuck opv or solenoid bolt. Nothing wrong with Allen-headed bolts from my perspective!

Definitely a rare occasion, this...


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## Bagpu55 (Dec 23, 2019)

Well so I bought a butane gun, a week of heating, cooling, tapping, soaking, praying, swearing. The little screw is still stuck solid it will not budge. Tried taking it to the local blacksmith but too intricate for him (I only do big stuff, I had to laugh). At this rate it might be coffee by xmas, cant say I havn't been patient with it. I might try taking it down to the local garden centre with the miniature steam train enthusiasts this weekend. Frustration!!


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## Tag1260 (Jun 17, 2019)

Clean it up the best you can and try soaking it for a couple of days in strong citric acid or vinegar. Might be scale and that might get it loose enough to move.

Hey, you've tried everything else so why not!!!!


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