Hi,

Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??

any help appreciated.

nige

On Mon, 27 Mar 2006 13:07:25 +0100, nige wrote:

They do unscrew anti clockwise dont they??

It's always worth turning a stuck nut clockwise, sometimes helps to
free it.

--
Nigel M

In article
nige wrote:
Hi,

Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??

Presumably you've already tried Plusgas. Heat would help, but it might
need oxy-acetylene rather than a propane torch. As a last resort
cutting them off is preferable to shearing studs.

Rob Morley wrote:
In article
nige wrote:
Hi,

Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??

Presumably you've already tried Plusgas. Heat would help, but it might
need oxy-acetylene rather than a propane torch. As a last resort
cutting them off is preferable to shearing studs.

I like heating to ~120C, then spraying with WD40, if possible.
The WD40 then boils, displacing air, and gets sucked in as it cools.

Rob Morley wrote:
In article
nige wrote:

Hi,

Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??


Presumably you've already tried Plusgas. Heat would help, but it might
need oxy-acetylene rather than a propane torch. As a last resort
cutting them off is preferable to shearing studs.

Propane should give the nut enough heat, but be careful if it is a cast
iron boiler. Cast iron likes to be heated uniformly. That's not to say a
propane torch will heat up the cast iron that much.

If the threads are corroded, even tightening them before removal may
well result in a sheared stud.

You have either to go for the heat, or use a nut splitter, available
from your local car accessory shop.

Dave

In article
Ian Stirling wrote:
Rob Morley wrote:
In article
nige wrote:
Hi,

Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??

Presumably you've already tried Plusgas. Heat would help, but it might
need oxy-acetylene rather than a propane torch. As a last resort
cutting them off is preferable to shearing studs.

I like heating to ~120C, then spraying with WD40, if possible.
The WD40 then boils, displacing air, and gets sucked in as it cools.

That method provides a bit of thermal shock which might be useful,
although I'm not sure that 120C is enough. I forgot to mention
attacking the exposed threads with a wire brush before undoing, and
wirebrushing everything and coating with copperease before reassembly.

Rob Morley wrote:
In article
Ian Stirling wrote:
Rob Morley wrote:
In article
nige wrote:
Hi,

Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??

Presumably you've already tried Plusgas. Heat would help, but it might
need oxy-acetylene rather than a propane torch. As a last resort
cutting them off is preferable to shearing studs.

I like heating to ~120C, then spraying with WD40, if possible.
The WD40 then boils, displacing air, and gets sucked in as it cools.

That method provides a bit of thermal shock which might be useful,
although I'm not sure that 120C is enough. I forgot to mention

It's probably not really.
This is for 'ordinarily' sticky bolts.

Hitting 170C (IIRC) causes the rust to start to change forms to a less
hydrated state, leading to it shrinking, and hopefully freeing up stuff.

Not to mention a bit of light hammering, using a suitable tube to hammer
the face of the nut.

Getting to 1700C frees even the stiffest nuts though

Ian Stirling wrote:
Rob Morley wrote:
nige wrote:
Trying to replace a heat exchanger on an ideal response 120
and the hexagon nuts wont budge a bit.
They do unscrew anti clockwise dont they??
Presumably you've already tried Plusgas. Heat would help, but it might
need oxy-acetylene rather than a propane torch. As a last resort
cutting them off is preferable to shearing studs.

I like heating to ~120C, then spraying with WD40, if possible.
The WD40 then boils, displacing air, and gets sucked in as it cools.

Sometimes heating nuts up, even to red hot, doesn't help. If
your stud's OK, you could snip your nuts off, and replace with
shiny new ones. Try bolt cutters, if you can fit them in.

On 27 Mar 2006 18:45:13 GMT, Ian Stirling
wrote:

I like heating to ~120C, then spraying with WD40, if possible.
The WD40 then boils, displacing air, and gets sucked in as it cools.

Except WD40 is a rather crap penetrating fluid. I find proper
penetrating fluid works much better (Plusgas or Halfords own brand)

Loctite now do something that works by freezing and penetrating.
Basically just a normal freezer spray (CO2?) and a penetrant combined.
On some really stubborn nuts (no I don't mean Dribble) on a
turbocharger exhaust manifold it worked really well. It also avoids
any possiblility of flareups as is usual when you have naked flames
and penetrating fluids.

I don't think it's available through retail outlets just yet though
but should be widely available from industrial suppliers - Loctite
Freeze and Release 8040 - about GBP5 for 400ml aerosol.




--

Matt wrote:
Except WD40 is a rather crap penetrating fluid.

Virtually useless on some things I've tried..

I find proper
penetrating fluid works much better (Plusgas or Halfords own brand)

Where can you get Plus Gas?

On Tue, 28 Mar 2006 08:52:22 +0100, Chris Bacon wrote:

Where can you get Plus Gas?

http://www.tool-up.co.uk/shop/diy/EAC803.html

--
Nigel M

Chris Bacon wrote in message
...
Matt wrote:
Except WD40 is a rather crap penetrating fluid.

Virtually useless on some things I've tried..


That's because WD40 is NOT a penetrating fluid. It's a water displacer (WD)
See http://www.ime.org.uk/ime/w/wd40.html



-- -

Thanks for your suggestions,
penetrating oil did the trick in
the end,

nige