I was given an old Cremina that has a leaky boiler seal. Two of the bolts that hold the boiler's heating element in place are frozen. A small soft brass screw where the boiler is bolted onto the frame is frozen as well. I've applied WD-40 overnight and tapped gently with a hammer but they're still firmly in place.

We have hard water here and the machine laid collecting dust for many years before it came my way. Could it be I'm dealing a combination of rust and calcium deposits?

Any tips on where to go from here? I'd really like to avoid breaking off a bolt head or damaging the brass screw. I've considered getting a propane torch but thought to ask you all first.

Thanks,
Jon

I found an article related to removing similar fasteners in a boating environment. Some of the tips may be useful. Look here.

Instead of a propane torch but along the same lines, try using one of those mini-butane torches typically used in the production of creme brulee. The idea being to heat and thus expand the surrounding metal - go gently.

Another idea, certainly not original, is to try tightening the fasteners a little and then attempt to remove. The idea being to break the corrosion and not the fastener.

roadman wrote:I was given an old Cremina that has a leaky boiler seal. Two of the bolts that hold the boiler's heating element in place are frozen. A small soft brass screw where the boiler is bolted onto the frame is frozen as well. I've applied WD-40 overnight and tapped gently with a hammer but they're still firmly in place.

Any tips on where to go from here? I'd really like to avoid breaking off a bolt head or damaging the brass screw. I've considered getting a propane torch but thought to ask you all first.

Well, first of all, I hate to tell you but the odds of getting a frozen brass screw out intact are small. I've had better luck with Aero Kroil than I have with WD-40. If it's hard water that's the problem, LimeAway can also be effective, although you need to be careful about where you put it. Your friends here are shock, heat, and penetrating oil. I agree that a small torch will help so you can carefully expand the surrounding surface. You may need to remove the head on the brass screw; sometimes getting the stress off the thread will allow it to come free. You may wind up drilling through the center of the brass screw and then picking out the pieces with a probe. That's the worst-case, but at least the brass is fairly easy to drill. Cheer yourself with the thought that at least you don't have to lie underneath the machine with oil dripping in your face while you work. Someday you'll be able to laugh about this.

Best,
David

Do you own a CO2 type of bicycle tube inflater? Try light heat, then hit with the CO2. The rapid change in temp can break loose seized parts. I've used this technique for loosening small bolts and larger parts on metal to metal contact bicycle components that were fused together due to corrosion or when people forgot to use anti-seize.

I second the Kroil idea. It is actually pretty amazing how well it works compared to other penetrants. You can find it at good hardware stores, and and any decent gun shop as it works quite well as a bore cleaner/conditioner also.

And if that doesn't work heating and shock cooling with the co2 is prolly your next step. You are wise to exercise patience and avoid breaking the bolts.

Tim

Ditto on the Kroil - it's one of the best for loosening frozen bolts!

Thanks one and all for the help and advice.

Kroil isn't available here so I'll see if I can find something similar in the meantime.

Sounds like I've got my work cut out for me.

Jon

Inox MX-3 is also a good penetrating lubricant that can be used to free up frozen fasteners, and it is food-safe:

http://www.inox-mx3.com/inox.htm


Might be hard to find here in the States in small quantities, as they're an Australian company still developing their distributorship here. I bought a couple of small cans last year from this distributor, but I do not know if they're still doing Inox distribution:

Audio Advancements LLC
10 bridle Way
Wantage, New Jersey 07461

Telephone: NINE SEVEN THREE EIGHT SEVEN FIVE EIGHT SEVEN ZERO FIVE
Fax: NINE SEVEN THREE EIGHT SEVEN FIVE EIGHT SEVEN THREE FIVE
Mob: NINE SEVEN THREE SEVEN ONE THREE THREE NINE FOUR THREE
Email: audadv[at]earthlink[dot]net


Regards
Timo

Here's the frozen bolt update.

They were soaked with penetrating oil for a couple weeks but wouldn't budge. They were then heated with a butane torch and still no dice. Finally took it to a machine shop. The guy there put a few drops of penetrating oil and heated the bolt with heat gun. Voilà the bolt yielded.

He said that in his experience the torch's flame burns off the penetrating oil, making it really hard to remove a stubborn bolt. In this case he appears to be right.

The brass screw was soaked down in liquid copper polish for several weeks as well, as Ralph's boating article suggested. Guess the corrosion was too nasty because in the end it needed to be drilled out.

Thanks again to one and all for the help and advice.

Jon