Insulation of expansion valve

Moderators: davidr, BigCatXJS, dhdove

davidr

Moderator
Posts: 1877
Joined: Thu Sep 08, 2005 8:31 pm
Location: Salisbury, Wilts

Insulation of expansion valve

Postby davidr » Sun Jan 17, 2016 9:37 pm

Evening all - I replaced the expansion valve in my 1989 V12 this weekend. There is a copper sensor coil that is connected to the bulb on the expansion valve. This is clamped to the outlet from the evaporator and is meant to feed back the temperature of the gas emerging from the evaporator in the cabin so the expansion valve opens and closes accordingly.
To ensure that it measures that output temperature and is not affected by the ambient temperature of the engine bay it is insulated.
I had to remove the insulation to install the new expansion valve and I'm not sure what to replace it with. Anyone got any ideas?
XJS FORUM COORDINATOR
1996 XJS Celebration Conv. (shown on the JEC stand at NEC Nov 2015)
2001 XKR Convertible

Previously enjoyed!
1989 XJ-S V12 Coupe. 2006 XJ TDVi Sovereign. 1995 XJ6 3.2. 2013 XF 2.2d. 2009 X Type 2.0d Sovereign estate

Brakebuster
Posts: 3131
Joined: Tue Apr 18, 2006 1:17 pm
Location: Gloucester UK

Re: Insulation of expansion valve

Postby Brakebuster » Sun Jan 17, 2016 11:04 pm

hmm

i too have to insulate this part

i will put on my thinking cap ,


BB
1989 5.3ltr V12 XJS Coupé FULLY RESTORED
2004 2.1V6 X-Type Saloon in platinum silver for the good wife
1994 3.2S XJ40 in Morocco Red with Doeskin interior

used to have
1999 4ltr Sovereign XJ8 in Seafrost

davidr

Moderator
Posts: 1877
Joined: Thu Sep 08, 2005 8:31 pm
Location: Salisbury, Wilts

Re: Insulation of expansion valve

Postby davidr » Sun Jan 17, 2016 11:26 pm

Hi BB - I guess it needs to be something that gives good thermal insulation and is heat resistant. I don't know if there's some kind of foam in a can?
I had considered using silicon rubber but I'm not sure how well that keeps the heat out.

ptjs1

Member
Posts: 2572
Joined: Thu Apr 27, 2006 7:14 pm
Location: Kent

Re: Insulation of expansion valve

Postby ptjs1 » Sun Jan 17, 2016 11:31 pm

David,

Could you cut a small piece (or two) of standard closed cell grey foam pipe lagging and then tie wrap it around the valve? Cheap to buy from B&Q or similar.

Paul
1995 XJS 4.0 Convertible
1980 XJ-S Pre-HE
Jaguar 4.2 Supercharged engine (but not with a Jaguar body..)

davidr

Moderator
Posts: 1877
Joined: Thu Sep 08, 2005 8:31 pm
Location: Salisbury, Wilts

Re: Insulation of expansion valve

Postby davidr » Sun Jan 17, 2016 11:38 pm

Hi Paul - I had considered that but it's not a straight forward shape. Previous stuff used was a gooey sticky substance which I guess was original.

User avatar
poprivet

Member
Posts: 1743
Joined: Mon Jan 16, 2006 3:20 pm
Location: Hampshire

Re: Insulation of expansion valve

Postby poprivet » Mon Jan 18, 2016 10:48 am

It seems to be a Self-Amalgamating putty or duct putty.

I think its more for holding things in place and sealing up the gaps more then purely insulating. I've seen similar stuff used by electricians to seal cable going through bulkheads.
1988 3.6 XJ-S coupe
'Remember that the value of your investment can plummet as well as fall'

Brakebuster
Posts: 3131
Joined: Tue Apr 18, 2006 1:17 pm
Location: Gloucester UK

Re: Insulation of expansion valve

Postby Brakebuster » Mon Jan 18, 2016 10:57 am

ah , if its what we call ' brown ' its as pop describes, though does not have ' insulating properties ' that I am aware of

I have some already , and can bring it along to Kemble

BB
1989 5.3ltr V12 XJS Coupé FULLY RESTORED
2004 2.1V6 X-Type Saloon in platinum silver for the good wife
1994 3.2S XJ40 in Morocco Red with Doeskin interior

used to have
1999 4ltr Sovereign XJ8 in Seafrost

davidr

Moderator
Posts: 1877
Joined: Thu Sep 08, 2005 8:31 pm
Location: Salisbury, Wilts

Re: Insulation of expansion valve

Postby davidr » Mon Jan 18, 2016 8:52 pm

This is the kind of thing I'm talking about. Lifted this image from Google - not sure what car it is - probably not even a Jag but it does show the gooey stuff used for insulation.
Attachments
image.jpeg


Who is online

Users browsing this forum: No registered users and 3 guests