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 25th August 2019, 17:41   #1
Mike Trident
Posted a thing or two
 
Mike Trident's Avatar
 
Rover 75 CDTi Saloon & Citroen C1

Join Date: Jun 2016
Location: Oakenshaw, Near Bradford
Posts: 1,618
Thanks: 385
Thanked 552 Times in 328 Posts
Default Serpentine belt tension?

When it's warm outside and I jump in start the car and the a/c cranks up to full. I move off and do a few full lock turns to the right and I get a loud groaning noise for the first few turns. It's done this for a couple of summers, so I keep putting it off. Like I said, it's only when the a/c is running flat out.

I am guessing a slightly loose serpentine belt, which slips a bit when under maximum load.

Do the tensioner wear out and need changing, or has the belt stretched enough that the tensioner can no longer keep it tight, or both?

Would like to hear your thoughts, anyone.
__________________
Rover 75 2.0 CDTi (131Ps) Conn SE Saloon. (Manual)
160 Remap, cruise control, electric window blind, temp gauge, Real walnut / ZT interior, FBH with GSM control.

BORN
Tuesday, 5th October 2004 @ 12:35:52
This vehicle was the 104,679th 75 to run off the production line, out of 112,381
This vehicle was the 3,318th 75 CDT Connoisseur SE (135) to be made out of 4,744
This vehicle was the 12,440th 75 in Starlight Silver (code: MBB) to be made out of 14,280 Starlight Silver 75s
Mike Trident is offline   Reply With Quote
Old 25th August 2019, 20:39   #2
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

The serpentine belt doesn't power the A/C compressor, so I doubt it's an aircon issue per se.





I also recall problems like this involving the power sterring pump (which is on the serpentine belt) and related to the mounting bolts I believe.


TC
T-Cut is offline   Reply With Quote
Old 25th August 2019, 22:30   #3
RogerHeinz57
I really should get out more.......
 
RogerHeinz57's Avatar
 
A Reasonably Priced Car

Join Date: Jan 2014
Location: Burton Latimer
Posts: 2,530
Thanks: 408
Thanked 1,064 Times in 712 Posts
Default

Also worth checking the condition of the crank pulley. Had one fail here but made no noises at all usually associated with pulley failure. The pulley was working correctly until a load was placed on it such as steering etc. The belt would stop turning the pulleys dead. Worth a check. Obviously if changing the belt set ensure all pulleys have minimal play or noise when rotated and are properly clean prior to belt installation.
RogerHeinz57 is offline   Reply With Quote
Old 25th August 2019, 23:11   #4
Mike Trident
Posted a thing or two
 
Mike Trident's Avatar
 
Rover 75 CDTi Saloon & Citroen C1

Join Date: Jun 2016
Location: Oakenshaw, Near Bradford
Posts: 1,618
Thanks: 385
Thanked 552 Times in 328 Posts
Default

Quote:
Originally Posted by T-Cut View Post
The serpentine belt doesn't power the A/C compressor, so I doubt it's an aircon issue per se.





I also recall problems like this involving the power sterring pump (which is on the serpentine belt) and related to the mounting bolts I believe.


TC
I figured it could be the extra load on the alternator when the fans are running flat out.

I really need to lift the bonnet with the a/c flat out and on full lock. See if I can see what's happening.

It only does it when extreme load is placed on the system. When the weather cools down and the a/c is only half load there will be no noise. Only when turning to the right for some reason, I am guessing the power steering pump works harder on right turns?
__________________
Rover 75 2.0 CDTi (131Ps) Conn SE Saloon. (Manual)
160 Remap, cruise control, electric window blind, temp gauge, Real walnut / ZT interior, FBH with GSM control.

BORN
Tuesday, 5th October 2004 @ 12:35:52
This vehicle was the 104,679th 75 to run off the production line, out of 112,381
This vehicle was the 3,318th 75 CDT Connoisseur SE (135) to be made out of 4,744
This vehicle was the 12,440th 75 in Starlight Silver (code: MBB) to be made out of 14,280 Starlight Silver 75s
Mike Trident is offline   Reply With Quote
Old 26th August 2019, 09:52   #5
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

You could check the steering system fluid level and the hydraulic connections,seals, etc. for leaks.


Try a keyword search for past threads on this issue. There are several.


TC
T-Cut is offline   Reply With Quote
Old 26th August 2019, 10:37   #6
Mike Trident
Posted a thing or two
 
Mike Trident's Avatar
 
Rover 75 CDTi Saloon & Citroen C1

Join Date: Jun 2016
Location: Oakenshaw, Near Bradford
Posts: 1,618
Thanks: 385
Thanked 552 Times in 328 Posts
Default

Quote:
Originally Posted by T-Cut View Post
You could check the steering system fluid level and the hydraulic connections,seals, etc. for leaks.


Try a keyword search for past threads on this issue. There are several.


TC
Yes, everything is fine. This only happens maybe 3 or 4 days a year when it's hot outside and the a/c turns the fans up to max when I start up.

This is why I have left it so long. When the summer has gone, it won't do it again until next year.
__________________
Rover 75 2.0 CDTi (131Ps) Conn SE Saloon. (Manual)
160 Remap, cruise control, electric window blind, temp gauge, Real walnut / ZT interior, FBH with GSM control.

BORN
Tuesday, 5th October 2004 @ 12:35:52
This vehicle was the 104,679th 75 to run off the production line, out of 112,381
This vehicle was the 3,318th 75 CDT Connoisseur SE (135) to be made out of 4,744
This vehicle was the 12,440th 75 in Starlight Silver (code: MBB) to be made out of 14,280 Starlight Silver 75s
Mike Trident is offline   Reply With Quote
Old 26th August 2019, 10:47   #7
Mike Trident
Posted a thing or two
 
Mike Trident's Avatar
 
Rover 75 CDTi Saloon & Citroen C1

Join Date: Jun 2016
Location: Oakenshaw, Near Bradford
Posts: 1,618
Thanks: 385
Thanked 552 Times in 328 Posts
Default

I have done a search and found a few interesting posts.

I am guessing this is going to be a process of elimination, starting with a new belt and tensioner.
__________________
Rover 75 2.0 CDTi (131Ps) Conn SE Saloon. (Manual)
160 Remap, cruise control, electric window blind, temp gauge, Real walnut / ZT interior, FBH with GSM control.

BORN
Tuesday, 5th October 2004 @ 12:35:52
This vehicle was the 104,679th 75 to run off the production line, out of 112,381
This vehicle was the 3,318th 75 CDT Connoisseur SE (135) to be made out of 4,744
This vehicle was the 12,440th 75 in Starlight Silver (code: MBB) to be made out of 14,280 Starlight Silver 75s
Mike Trident is offline   Reply With Quote
Old 26th August 2019, 18:17   #8
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 Mike Trident View Post
This only happens maybe 3 or 4 days a year when it's hot outside and the a/c turns the fans up to max when I start up.

So your radiator cooling fan runs at high speed when the aircon is switched on in hot weather. I can see how it could, but I don't think it's normal. The normal aircon cooling fan is at low speed, which trips to high/higher speed if it's overheating/stressed. The system should cope with anything the UK can throw at it, though ambients of 30+ Centigrade might test it I suppose. However, I get the impresssion this effect has persisted over several summers, including the usual variety?


TC
T-Cut is offline   Reply With Quote
Old 26th August 2019, 20:14   #9
Mike Noc
This is my second home
 
Mike Noc's Avatar
 
Rover 75 CDT Manual Connoisseur SE, Rover 75 CDT Automatic Connoisseur SE & a Freelander Td4.

Join Date: Jul 2009
Location: Hampshire
Posts: 11,531
Thanks: 3,470
Thanked 3,119 Times in 2,247 Posts
Default

Hate to state the obvious but why not drive with a bit of mehanical sympathy and avoid using full lock?


At full lock you are loading up the power steering hydrulics.
Mike Noc is offline   Reply With Quote
Old 27th August 2019, 05:53   #10
Mike Trident
Posted a thing or two
 
Mike Trident's Avatar
 
Rover 75 CDTi Saloon & Citroen C1

Join Date: Jun 2016
Location: Oakenshaw, Near Bradford
Posts: 1,618
Thanks: 385
Thanked 552 Times in 328 Posts
Default

Lol, difficult when manuvering out of a Costa coffee car park.


No, it's not the external fan that runs at high speed it's the interior blower fan. If the car has been parked in the sun, the a/c will crank the interior blower up to the max for a while to get the cabin temp down.

As you can see, from both comments I have written above they are linked. Jump into car after a bit of shopping or a coffee. Car has been parked in the sun, and in a car parking bay. Start car, a/c ramps up the interior blower to full speed, full lock needed to get out of the car park.

Yes, I understand the mechanical sympathy bit. But a car that can't be driven in a car park is not exactly fit for purpose.
__________________
Rover 75 2.0 CDTi (131Ps) Conn SE Saloon. (Manual)
160 Remap, cruise control, electric window blind, temp gauge, Real walnut / ZT interior, FBH with GSM control.

BORN
Tuesday, 5th October 2004 @ 12:35:52
This vehicle was the 104,679th 75 to run off the production line, out of 112,381
This vehicle was the 3,318th 75 CDT Connoisseur SE (135) to be made out of 4,744
This vehicle was the 12,440th 75 in Starlight Silver (code: MBB) to be made out of 14,280 Starlight Silver 75s

Last edited by Mike Trident; 27th August 2019 at 05:57..
Mike Trident 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 10:54.


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