Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club General Forum
Register FAQ Image Gallery Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
Old 6th December 2011, 07:20   #1
fintious maximus
Newbie
 
Rover 75 saloon

Join Date: Dec 2011
Location: Sheffield
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Default heater blowing cold andwindscreen misting

Hi all, posting on behalf of my dadand his beloved75 2.0cdti.....

his windscreen mists throughout the year and now cold weather is here the heater won't blow hot air. Also needs air con regassing as doesn't blow really cold in summer.

Any suggestions? Thoughts are possibly heater matrix/thermostat.....
fintious maximus is offline   Reply With Quote
Old 6th December 2011, 07:27   #2
scouseeric
Passed On
 
scouseeric's Avatar
 
75 contemporary se cdti

Join Date: Dec 2010
Location: Liverpool
Posts: 1,582
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Good morning Andy, i think you may need another 'stat fitted in the top hose. Welcome to the club!:xmas-smiley-003:

Eric
__________________
curteous driving costs nothing - free with every rover 75

OBD2 SCANNER AVAILABLE TO USE LOCALLY
scouseeric is offline   Reply With Quote
Old 6th December 2011, 10:58   #3
Unclefista
It was on fire when I got here..
 
Unclefista's Avatar
 
Rover 75 CDT

Join Date: Sep 2011
Location: Bradford
Posts: 1,479
Thanks: 1
Thanked 6 Times in 6 Posts
Default

Quote:
Originally Posted by fintious maximus View Post
Hi all, posting on behalf of my dadand his beloved75 2.0cdti.....

his windscreen mists throughout the year and now cold weather is here the heater won't blow hot air. Also needs air con regassing as doesn't blow really cold in summer.

Any suggestions? Thoughts are possibly heater matrix/thermostat.....
You need to find out if your thermostat is stuck open, there's a way of displaying the OBD coolant temp on the dash if you have a search, that should tell you whether the thermostat is working.
If the thermostat is fine, next thing I'd look at is coolant level, too low and it doesn't reach the matrix.
After that I'd remove the matrix (easy job) and either replace or clean it out.

All my own opinion, if anyone has anything else to add I'd welcome it
__________________
Love is like a snowmobile, speeding across the frozen tundra.
Which suddenly flips, pinning you underneath.
At night the ice-weasels come...

Unclefista is offline   Reply With Quote
Old 6th December 2011, 11:10   #4
kissifer1972
Posted a thing or two
 
Rover 75 CDTi Conn Tourer & Rover 75 CDT Conn SE Saloon

Join Date: May 2010
Location: Queensbury
Posts: 1,368
Thanks: 0
Thanked 1 Time in 1 Post
Default

Regarding the misting, has anyone checked that his plenums are clear of water?

The misting could be, and usually is, down to the pollen filter being wet from water in the plenum chamber. That needs sorting as a matter of urgency.

It could also be that his radiator fan is not working and therefore not cooling the air con condensor causing his air con to not blow cold. A common fault.

Chris
__________________
Mods so far
X-Power Performance Upgrade
LED interior lights and sidelights
Genuine Rover Xenons - now removed and sold
Kenlowe fan
Synergy 2
EGR Bypass

Last edited by kissifer1972; 6th December 2011 at 19:03..
kissifer1972 is offline   Reply With Quote
Old 6th December 2011, 16:43   #5
fintious maximus
Newbie
 
Rover 75 saloon

Join Date: Dec 2011
Location: Sheffield
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Default

thanks for the replies guys. Popped round to see him this morning and checked coolant level which was fine. Started her up and after ten or so mins the temp guage had hardly moved from cold - does this point to thermostat?

Also, what and where is the plenum chamber?
fintious maximus is offline   Reply With Quote
Old 6th December 2011, 19:11   #6
kissifer1972
Posted a thing or two
 
Rover 75 CDTi Conn Tourer & Rover 75 CDT Conn SE Saloon

Join Date: May 2010
Location: Queensbury
Posts: 1,368
Thanks: 0
Thanked 1 Time in 1 Post
Default

Quote:
Originally Posted by fintious maximus View Post
thanks for the replies guys. Popped round to see him this morning and checked coolant level which was fine. Started her up and after ten or so mins the temp guage had hardly moved from cold - does this point to thermostat?

Also, what and where is the plenum chamber?
Did you have a feel of the pipe to the radiator? Did it feel warm? After tens mins, even with the thermostat open, the temp gauge should have moved off cold, maybe not to 9 O'clock but moved quite a bit. I wonder if the temp sensor is shot?

Anyway the plenums are under the plastic covers at the rear of the engine bay, just in front of the windscreen. The driver's side one is the easiest to check for water through. Unclip it and remove and look for water in the bottom. I would bet there is some in there as, if unchecked, the drains clog up and water builds up in there. Potentially disastrous, as I recently found out, if your ECU gets wet.

Here is a pic of the driver's side plenum cover http://www.ephestione.it/uploads/2011/03/IMAG0742.jpg

Be careful if you have to remove the scuttle panel - the bit that runs along the bottom of the windscreen - as the oval shaped clips that hold it down ping off everywhere - put a little masking tape over each one as one tip I've seen - or have someone who is good at catching handy as you tug it free.

To check the fan with the ignition in position 2 - turn the heater to demist the screen - you should hear the fan run.

HTH

Chris
__________________
Mods so far
X-Power Performance Upgrade
LED interior lights and sidelights
Genuine Rover Xenons - now removed and sold
Kenlowe fan
Synergy 2
EGR Bypass
kissifer1972 is offline   Reply With Quote
Old 7th December 2011, 16:35   #7
fintious maximus
Newbie
 
Rover 75 saloon

Join Date: Dec 2011
Location: Sheffield
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Temp guage did move a bit to maybe 7 o'clock position.... Didn't feel pipes though.

Anyway today I nipped into Unipart to get a thermostat to give that a try until I discovered that it was £60 (usually pay around a fiver) - it isn't a straight forward part though. So before I spend that much on a 'try' is there anyway of telling that the stat does work?
fintious maximus is offline   Reply With Quote
Old 7th December 2011, 19:16   #8
SD1too
This is a real leaf!
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Middlesex
Posts: 8,474
Thanks: 148
Thanked 442 Times in 418 Posts
Default

Hi Andy,

The 7 o'clock position on the temperature gauge translates to a coolant temperature of 55 degrees. I don't think you'll be wasting your money replacing the thermostat! It's a very common fault on the diesel according to this forum.

Simon.
__________________
Confidence is what you have before you understand the problem.
(Woody Allen)
SD1too is offline   Reply With Quote
Old 7th December 2011, 21:47   #9
kissifer1972
Posted a thing or two
 
Rover 75 CDTi Conn Tourer & Rover 75 CDT Conn SE Saloon

Join Date: May 2010
Location: Queensbury
Posts: 1,368
Thanks: 0
Thanked 1 Time in 1 Post
Default

There is a much cheaper fix than the genuine stat - you can fit one in the top hose - costs about £10

You'll have to have a search on here for details - look for inline stat diesel

see here http://www.the75andztclub.co.uk/foru...ne+stat+diesel

Chris
__________________
Mods so far
X-Power Performance Upgrade
LED interior lights and sidelights
Genuine Rover Xenons - now removed and sold
Kenlowe fan
Synergy 2
EGR Bypass

Last edited by kissifer1972; 7th December 2011 at 21:51..
kissifer1972 is offline   Reply With Quote
Old 8th December 2011, 18:10   #10
fintious maximus
Newbie
 
Rover 75 saloon

Join Date: Dec 2011
Location: Sheffield
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Thanks for the info thus far. Going to get a proper stat cos me dad likes it that way!

Just had the car in my garage and took the plastic grids off to expose pollen filter which was in about an inch of water and the filter was a black gooey mess. Managed to prod the drain hole and a torrent of water was released so hopefully that will solve the misting up problem.........

Stat on Sunday and then hopefully job done!
fintious maximus is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 10:24.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright © 2006-2014, The Rover 75 & MG ZT Owners Club Ltd