Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 31st October 2019, 23:12   #11
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

Quote:
Originally Posted by TOMPARKER44 View Post
T-cut - will try (this evening) and get that to work but don't have a trip computer on my car, would be useful to see engine temp though!
The trip mileage reset button is what you use. All 75/ZTs have one and all can run in Diagnostic Mode. Read the HowTo and you can't go wrong.

EDIT: Ah, I see you've twigged it.


TC

Last edited by T-Cut; 31st October 2019 at 23:15..
T-Cut is online now   Reply With Quote
Old 1st November 2019, 00:42   #12
Briodyjl01
Gets stuck in
 
Rover 75 Tourer, Rover 75 Saloon

Join Date: May 2018
Location: Castleford
Posts: 959
Thanks: 237
Thanked 185 Times in 113 Posts
Default

Quote:
Originally Posted by T-Cut View Post
As a diesel, it may well be suffering the widespread problem of the underperforming thermostat. It's very common and has filled reams of forum space over the years. Of course, you won't get any heating if the coolant's not hot enough, so I'd suggest you first check the actual running temperaure. Don't rely on the temperature gauge to tell to anything. The pointer at 'normal' means very little. If it runs below the 'normal' point, you know it's below 75C, which is pretty poor for everything, heating, fuel economy and engine wear. So, run the Trip Screen Diagnostic test while driving normally and tell us the result. You want it near 90C.


HowTo (see section 7): https://www.the75andztclub.co.uk/for...ad.php?t=55585





Diesel owners with the low temperature running issue typically fit the in-line thermostat modification with good results. Choose the stat carefully though using advice on here.


TC

I have done the coolant temp check and it is reading high 80s to high 90s but fluctuating up and down a lot between them number. But the heater is still freezing and like the original poster said about 2500 RPM it starts to get warm then drops cold again when you slow down
__________________
Too many Rovers to count ……
Briodyjl01 is offline   Reply With Quote
Old 1st November 2019, 09:04   #13
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,265
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

Quote:
Originally Posted by Briodyjl01 View Post
... my cdt just drinks coolant. there is supposed to be a leak somewhere but I cant seem to find it.
Quote:
Originally Posted by Briodyjl01 View Post
... it is reading high 80s to high 90s but fluctuating up and down a lot ... But the heater is still freezing ... about 2500 RPM it starts to get warm then drops cold again when you slow down
Josh; the most likely reason for this is that your cooling system isn't pressurising probably due to an ineffective seal between two components or, for example, a tiny defect in the radiator. These can be very hard to find and won't necessarily result in a stream of visible coolant.

The other possibility is an air lock particularly if work has been carried out and the proper refilling/bleeding procedure not followed.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Old 1st November 2019, 09:06   #14
Number 6
This is my second home
 
Rover 75 tourer Club CD/Limo Tints

Join Date: Nov 2008
Location: Meneac
Posts: 6,759
Thanks: 5,007
Thanked 1,609 Times in 869 Posts
Default

Quote:
Originally Posted by Briodyjl01 View Post
very interested in this!!!!!!

my cdt just drinks coolant. there is supposed to be a leak somewhere but I cant seem to find it. Every time I fill the bottle up its empty by the next time I look in it. the temp doesn't over heat. The heater / AC sometimes gets warm but normally i just blows cold.
Check your oil level!!! Is it going up?
__________________
]

"I started out with nothing, and Ive still got most of it left!"
Number 6 is offline   Reply With Quote
Old 1st November 2019, 10:15   #15
Briodyjl01
Gets stuck in
 
Rover 75 Tourer, Rover 75 Saloon

Join Date: May 2018
Location: Castleford
Posts: 959
Thanks: 237
Thanked 185 Times in 113 Posts
Default

Quote:
Originally Posted by SD1too View Post
Josh; the most likely reason for this is that your cooling system isn't pressurising probably due to an ineffective seal between two components or, for example, a tiny defect in the radiator. These can be very hard to find and won't necessarily result in a stream of visible coolant.

The other possibility is an air lock particularly if work has been carried out and the proper refilling/bleeding procedure not followed.

Simon

When I bleed it I do it the same way I do my metros, open the bleed screw next to the battery and put a funnel n the coolant bottle and fill that with coolant to force the air out. I know that works on them.
__________________
Too many Rovers to count ……
Briodyjl01 is offline   Reply With Quote
Old 1st November 2019, 10:16   #16
Briodyjl01
Gets stuck in
 
Rover 75 Tourer, Rover 75 Saloon

Join Date: May 2018
Location: Castleford
Posts: 959
Thanks: 237
Thanked 185 Times in 113 Posts
Default

someone said earlier on in the post about 2500 rpm and it gets warm. this is what mines doing as well.
__________________
Too many Rovers to count ……
Briodyjl01 is offline   Reply With Quote
Old 1st November 2019, 11:10   #17
trikey
Premium Trader
 
trikey's Avatar
 
Rover 75

Join Date: Nov 2010
Location: Devon
Posts: 33,711
Thanks: 8,837
Thanked 14,831 Times in 8,030 Posts
Default

You have an airlock Josh, I would remove the hoses that go to the matrix and back flush them, then refill and bleed correctly and see what happens.
__________________
Lest we forget..
trikey is offline   Reply With Quote
Old 1st November 2019, 11:21   #18
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,265
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

And here is the correct method of refilling/bleeding a 75/ZT diesel Josh.

To increase your chances of success at the first attempt, I would follow MG Rover's recommendation that the system is first fully drained (after which you can back-flush the heater matrix as Trikey suggests) including the cylinder block drain plug.

I don't have a diesel, I have a petrol 75, but by following the MGR procedure for my engine exactly, I have never had an air lock, overheating or poor heater performance.

Let us know how you get on.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too 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 19:50.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd