siezed bolts

WD40/penetrating oil and leave it for an hour or so to do its stuff. You then need a strong socket and a long bar. It may actually help to try tightening it 1/4 turn before loosening it.

I have to agree with this, and in really extreme cases you may wish to heat the offending fastener with a blowtorch to warm it up a bit - just to get it to 'move'.

Make sure you get the socket on well and really 'focus' on moving it - this is the only way as profanity, a machine gun or a bigger hammer rarely work.....

Artie

IME none of the so called penetrating oils actually penetrate a rusty or siezed thread. I still use it because I live in hope, but I don't really believe it does any good. On the few occasions I've soaked a rusty thread with the stuff, and then unscrewed it or cut it off without reapplying more, the thread has invariably been dry. It probably helps once the bolt has moved, as in effect that cracks the seal, allowing it to creep along the thread. OTOH, an oxy acetylene torch works every time, although I do appreciate that it's not a method available to most DIYers. Mike.

Loctite have a product called "Freeze and Release" which claims to work on the principle of freezing the seized or rusted part to minus 40 degrees which causes minute cracks allowing the lubricant to penetrate by capilliary action. I have never used it so can't say it if is any good. See:

I've used a blowlamp on the area outside the bolt as far as possible, followed by pipe freezer spray (Arctic Spray as sold in plumbing stores) on the bolt to give the joint a shock. As I also used penetrating oil (Plusgas is better than WD40 I think) I reckon I beat Loctite to this discovery by some 15 yrs. Seriously, it's not a new idea and it works perhaps 70% of the time.

Indeed - minus 40 degrees is only 50-ish degrees off ambient temperature, a blowlamp followed by a good squirt of WD40 works fine in many cases. For jobs like getting balljoints off swivel hubs I sometimes just stick the whole lot on top of the gas cooker for a while, then give it a squirt. Life was easier when I could borrow the oxy- acetylene gear from work, though ...

They do..you just have to leave it long enough. With the age of cars I'm currently spannering on, it's pretty much an essential.

I tried it. It didn't really freeze, and it most certainly didn't release.

What was more worrying is after noticing it didn't seem to live up to the first bit of its name, I sprayed it on myself... And was at best as mildly chilled as you'd expect from the expansion of a compressed gas.

I'm thinking about finding a suitable nozzle for a can of butane lighter gas, as that certainly seems to cool a great deal more. The idea being to freeze with that, then quickly spray Plusgas on as well. Haven't got anything I really feel like taking apart just to test the idea though.

Don't know if this will work but I noticed Maplins sell a can of Freezer spray which says it can freeze small bore pipes to carry out repairs without the need to drain. According to their FAQ's it is alcohol based and cools the object by the evaporation of the ethyl.

What is it that you can't get out? Is it that the head of the bolt is damaged or there's not enough room to get a socket or (ring) spanner on. I have a few pieces of old pipe I use as extension bars when I'm doing brake stuff and provided I can get something on the bolt heads it usually works sometimes also needing the use of a big hammer.