Oh jeez, where do i start? - Page 3

bl52krz · 4th April 2022, 21:56

Can not wait for the finale on this NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD- up. Have a look at the bolt that holds the header tank in to see if it is scuffed from undoing it to raise the tank up. Bet it isn’t.

SD1too · 5th April 2022, 07:11

Quote:

Originally Posted by bl52krz

Have a look at the bolt that holds the header tank in to see if it is scuffed from undoing it to raise the tank up. Bet it isn’t.

That was one of the pieces of evidence I noted David. You're right, it's still nicely coated in light rust.

Simon

YMGF · 5th April 2022, 13:29

Simon, I did that thermostat replacement job a few months ago and think (hope!) I put the clips the correct way up. I may be missing something very obvious, but do you know the reason for having the clips a particular way up though? It wasn't clear to me how they function or why it would matter.
Michael.

SD1too · 5th April 2022, 18:53

There seems to be more to this car than meets the eye. The amount of coolant drained (5 litres) was short of the capacity (7.2 litres). Following the bleeding procedure the expansion tank filled up much earlier than the other KV6s I've worked on, including my own.

The initial test. drive was encouraging but now we're back to square one; rapidly varying temperature readings (for example 97 to 102 in two seconds) and one instance of 111˚ yet the top radiator hose doesn't reflect this and the bottom radiator hose is tepid.

I think there's still an air lock and this car has the modified oil cooler circuit. I intend to drain that tomorrow as this worked on another member's car last summer.

Simon

lida · 6th April 2022, 07:30

Spent yesterday, Tuesday, with Simon. After a sterling job the same problem remained – erratic coolant temperature, rising or falling in milliseconds. The two radiator hoses remain warm and touchable, when in fact they should be scorching.

If we cannot solve the issue today, then I will take my Rover back to the garage to establish my legal situation. I need to allow them to see the problem in action.

I later realised what they meant by having kept an eye on the temp/fan after the works and before I collected the car last week. I think they checked the temp gauge on the dash and saw that it did not change at all. I did explain to them that a peculiarity of the V6 is that the temp gauge needle will not fluctuate. The first time a driver without experience of this car will know there is a problem is when that needle zooms up towards the red mark.

I think that's why they were so shocked when I said that I was observing the cooling system temperature via the onboard diagnostic that T-Cut and others have spoken of.

dave lincs · 6th April 2022, 07:39

Hi Lida just a thought does the heater get hot in the car when on high and stay hot with the car ticking over?

SD1too · 6th April 2022, 10:22

Quote:

Originally Posted by dave lincs

Hi Lida just a thought does the heater get hot in the car when on high and stay hot with the car ticking over?

I checked that Dave and yes it does.

Simon

Arctic · 6th April 2022, 11:58

Hi Simon.
Did you take the car for a run get it up to thermostat opening temp, then switch the heating on to highest temp it can go and have the internal fan blowing as hard as it can? try that and see if the air block goes.

SD1too · 6th April 2022, 17:20

Today I drained the cooling system once more but this time I included the oil cooler hoses (the later connections in the heater return to cylinder head circuit). It made no difference.

The abnormal behaviour is as follows:

Following bleeding, when the engine is started the level in the expansion tank does not drop to allow coolant to be added as described in RAVE.
When the expansion tank cap is refitted, the temperature quickly climbs to 100˚ which is unusual at idle in Spring temperatures.
The slow speed fan is unable to cool the engine. It remained at 100˚ even increasing to 101˚.
When the engine speed is raised to 2,000 rpm the temperature drops quickly to 95˚. Release the accelerator and it climbs equally quickly back up to 100˚.
The bottom radiator hose remains tepid throughout.

The main dealer had renewed the thermostat housing invoicing specifically for the MGR part number. The above evidence suggests to me that this new thermostat is opening only partially, i.e. it's faulty.

Lida's problem is that from her conversations with the dealer, it is clear that they have scant knowledge of how the KV6 cooling system works. They believe that yesterday's driving temperature of 106˚ with the fan running is normal (my 75 in identical circumstances reads 91˚).

There is little chance that the garage will agree to change Lida's thermostat again.

Simon

PS Thanks Steve (Arctic) for your question. Yes, during yesterday's test drive we did set the heater to 'Hi' with the blower at full blast but it did not change the temperature reading.

dave lincs · 6th April 2022, 17:30

If it is the later oil cooler bypass it the try it again the do block causing the problem you have or use a laser thermometer and check hoses etc and pinpoint any cold areas

Ps I have fitted a few oil coolers for ver similar problems but bypass it and see what happens

Dave

4th April 2022, 21:56	#21
bl52krz This is my second home Rover 75 cdt club + Rover 2.5 KV6 Conni SE Join Date: May 2008 Location: Birmingham Posts: 11,387 Thanks: 6,587 Thanked 2,262 Times in 1,729 Posts	Can not wait for the finale on this NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD- up. Have a look at the bolt that holds the header tank in to see if it is scuffed from undoing it to raise the tank up. Bet it isn’t. __________________ Great Barr, Birmingham. Last edited by bl52krz; 4th April 2022 at 21:57.. Reason: Naughty word was cockup

5th April 2022, 18:53	#24
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,344 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	A disappointing day There seems to be more to this car than meets the eye. The amount of coolant drained (5 litres) was short of the capacity (7.2 litres). Following the bleeding procedure the expansion tank filled up much earlier than the other KV6s I've worked on, including my own. The initial test. drive was encouraging but now we're back to square one; rapidly varying temperature readings (for example 97 to 102 in two seconds) and one instance of 111˚ yet the top radiator hose doesn't reflect this and the bottom radiator hose is tepid. I think there's still an air lock and this car has the modified oil cooler circuit. I intend to drain that tomorrow as this worked on another member's car last summer. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

6th April 2022, 11:58	#28
Arctic Give to Learn Freelander 2 Join Date: Aug 2010 Location: West Midlands Posts: 18,700 Thanks: 1,155 Thanked 6,407 Times in 3,874 Posts	Hi Simon. Did you take the car for a run get it up to thermostat opening temp, then switch the heating on to highest temp it can go and have the internal fan blowing as hard as it can? try that and see if the air block goes. __________________ Arctic Givology Learn to Give Everything is Achievable ad altiora tendo. Check out our Nano meet dates http://www.midlandsnanomeets.co.uk/ http://www.the75andztclub.co.uk/index.php?thepage=howto " You do the work , we supply the expertise "

6th April 2022, 17:20	#29
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,344 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	Today I drained the cooling system once more but this time I included the oil cooler hoses (the later connections in the heater return to cylinder head circuit). It made no difference. The abnormal behaviour is as follows: Following bleeding, when the engine is started the level in the expansion tank does not drop to allow coolant to be added as described in RAVE. When the expansion tank cap is refitted, the temperature quickly climbs to 100˚ which is unusual at idle in Spring temperatures. The slow speed fan is unable to cool the engine. It remained at 100˚ even increasing to 101˚. When the engine speed is raised to 2,000 rpm the temperature drops quickly to 95˚. Release the accelerator and it climbs equally quickly back up to 100˚. The bottom radiator hose remains tepid throughout. The main dealer had renewed the thermostat housing invoicing specifically for the MGR part number. The above evidence suggests to me that this new thermostat is opening only partially, i.e. it's faulty. Lida's problem is that from her conversations with the dealer, it is clear that they have scant knowledge of how the KV6 cooling system works. They believe that yesterday's driving temperature of 106˚ with the fan running is normal (my 75 in identical circumstances reads 91˚). There is little chance that the garage will agree to change Lida's thermostat again. Simon PS Thanks Steve (Arctic) for your question. Yes, during yesterday's test drive we did set the heater to 'Hi' with the blower at full blast but it did not change the temperature reading. __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

6th April 2022, 17:30	#30
dave lincs Posted a thing or two Rover 75 Saloon Join Date: Mar 2014 Location: Louth Posts: 1,409 Thanks: 380 Thanked 986 Times in 476 Posts	If it is the later oil cooler bypass it the try it again the do block causing the problem you have or use a laser thermometer and check hoses etc and pinpoint any cold areas Ps I have fitted a few oil coolers for ver similar problems but bypass it and see what happens Dave Last edited by dave lincs; 7th April 2022 at 17:36..

5th April 2022, 13:29	#23
YMGF Regular poster Rover 75 Saloon Join Date: Jul 2020 Location: Oxford Posts: 68 Thanks: 33 Thanked 12 Times in 8 Posts	Simon, I did that thermostat replacement job a few months ago and think (hope!) I put the clips the correct way up. I may be missing something very obvious, but do you know the reason for having the clips a particular way up though? It wasn't clear to me how they function or why it would matter. Michael.

6th April 2022, 07:30	#25
lida Regular poster Rover 75 Tourer 2.5 V6 Join Date: Feb 2014 Location: West Middlesex Posts: 63 Thanks: 48 Thanked 11 Times in 6 Posts	Spent yesterday, Tuesday, with Simon. After a sterling job the same problem remained – erratic coolant temperature, rising or falling in milliseconds. The two radiator hoses remain warm and touchable, when in fact they should be scorching. If we cannot solve the issue today, then I will take my Rover back to the garage to establish my legal situation. I need to allow them to see the problem in action. I later realised what they meant by having kept an eye on the temp/fan after the works and before I collected the car last week. I think they checked the temp gauge on the dash and saw that it did not change at all. I did explain to them that a peculiarity of the V6 is that the temp gauge needle will not fluctuate. The first time a driver without experience of this car will know there is a problem is when that needle zooms up towards the red mark. I think that's why they were so shocked when I said that I was observing the cooling system temperature via the onboard diagnostic that T-Cut and others have spoken of.

6th April 2022, 07:39	#26
dave lincs Posted a thing or two Rover 75 Saloon Join Date: Mar 2014 Location: Louth Posts: 1,409 Thanks: 380 Thanked 986 Times in 476 Posts	Hi Lida just a thought does the heater get hot in the car when on high and stay hot with the car ticking over?