|
||
|
31st October 2021, 15:56 | #1 |
Newbie
Rover 75 Saloon Join Date: Feb 2021
Location: Anytown
Posts: 28
Thanks: 0
Thanked 1 Time in 1 Post
|
Hot air fine when moving, but cool stationary?
Hi all.
Got a perplexing problem at moment, especially with winter coming. I have a R75 Connie 2.5v6 petrol auto. It's had a replacement stat a year ago, no leaks or drop in coolant level, but my mechanic fixed a leak from the short straight plastic pipe a few months ago. I think he put some kind of rad fix solution in, which I wasn't happy about. After that I had no hot air. I asked him to flush out all the coolant and replace, and while at it flush out the matrix. Since then coolant seems fine, no loss, and car runs fine, but hot air is fine when car is moving forward but as soon as you stop, (with engine running) the cabin air drops to just barely warm. Start moving forward and goes hot again??? When running the engine runs at around 81° which I know is a bit cool, but the hot air is fine when moving. Air con was degassed and checked about six months ago. Any ideas? Thanks Last edited by Fred Pitt; 31st October 2021 at 15:57.. Reason: Mistake |
31st October 2021, 17:07 | #2 |
Loves to post
Rover75 tourer Join Date: Jun 2018
Location: Ashton
Posts: 428
Thanks: 121
Thanked 206 Times in 145 Posts
|
When you say " but hot air is fine when car is moving forward but as soon as you stop, (with engine running) the cabin air drops to just barely warm. Start moving forward and goes hot again??? "
I presume you have the heater fan running at a reasonable speed both when moving and when stationary ?
__________________
Common sense isn't a gift, it's a punishment because you have to deal with everyone who doesn't have it. |
31st October 2021, 20:09 | #3 |
Premium Trader
Rover 75 Join Date: Nov 2010
Location: Devon
Posts: 33,802
Thanks: 8,837
Thanked 14,831 Times in 8,030 Posts
|
You have an airlock!!!
__________________
Lest we forget..
|
1st November 2021, 06:58 | #4 |
Doesn't do things by halves
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,446
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
|
That's my first thought too. There's a specific procedure for refilling and bleeding the KV6. How handy are you with the spanners Darren? Oh, and steer clear of that mechanic. Putting sealing potions in the coolant can, and has caused catastrophic long term problems. Simon
__________________
"Whatever is rightly done, however humble, is noble." Sir Henry Royce. |
3rd November 2021, 07:54 | #5 | |
Newbie
Rover 75 Saloon Join Date: Feb 2021
Location: Anytown
Posts: 28
Thanks: 0
Thanked 1 Time in 1 Post
|
Quote:
|
|
3rd November 2021, 07:57 | #6 | |
Newbie
Rover 75 Saloon Join Date: Feb 2021
Location: Anytown
Posts: 28
Thanks: 0
Thanked 1 Time in 1 Post
|
Quote:
What's annoying is I asked him to do a coolant system flush and refill, and and assume he would follow rover procedures. Do I need to empty it again and refill, following rover kv6 procedures? |
|
3rd November 2021, 07:57 | #7 |
Newbie
Rover 75 Saloon Join Date: Feb 2021
Location: Anytown
Posts: 28
Thanks: 0
Thanked 1 Time in 1 Post
|
|
3rd November 2021, 09:21 | #8 | |
Doesn't do things by halves
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,446
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
|
Quote:
Unfortunately garages are under pressure to work as quickly as possible so don't have the time to look through workshop manuals for any special requirements, particularly when those manuals were, as in MG Rover's case, on CD ROM. Please keep us updated! Simon
__________________
"Whatever is rightly done, however humble, is noble." Sir Henry Royce. |
|
3rd November 2021, 12:41 | #9 |
Gets stuck in
75 Tourer CDT MK2 manual in Glorious Grey Join Date: Jan 2018
Location: Slovakia
Posts: 987
Thanks: 926
Thanked 346 Times in 252 Posts
|
People who are smarter and more experienced with the 75 than I say an airlock is the likely culprit. Who am I to argue with that? They're probably correct.
The one other thing that comes to mind, though, is the possibility that the heater core (matrix) may still be restricted with the remnants of the goop that was put in to fix the original leak. That stuff is just evil. Some heater cores have smaller passages than radiators. I'd be prepared for another flush - maybe even just the core through the heater hoses and with a cleaning agent or vinegar or something. If the drain/refill process doesn't do the job... Good luck, Glenn
__________________
Southern Slovakia Anything can happen in Formula 1 and usually does - Murray Walker 1999 Triumph Trophy 900, Saddlesore 1600, Iron Butt Riders Association #63720 2005 Rover 75 CDT Tourer MK2 |
3rd November 2021, 14:16 | #10 | |
Doesn't do things by halves
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,446
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
|
Quote:
Hmmm, that's around 10° too cool so your thermostat has probably been sealed in a partial or fully open position. Your going to need several flushes using a cleaning agent and another new thermostat which should all be at the garage's expense, not yours. Simon
__________________
"Whatever is rightly done, however humble, is noble." Sir Henry Royce. |
|
|
|