top hose not pressurising when engine up to temperature

johnpilky · 31st July 2018, 19:54

hi,top hose not pressurissing when engine up to temperature any ideas thanks

SD1too · 31st July 2018, 20:08

What is the engine’s normal running temperature John?

Simon

johnpilky · 31st July 2018, 21:47

Quote:

Originally Posted by SD1too

What is the engine’s normal running temperature John?

Simon

hi pal about 90 degrees

SD1too · 1st August 2018, 07:05

When you’re stationary in traffic, does the temperature slowly rise to 104 degrees (with air conditioning off)?

Simon

johnpilky · 1st August 2018, 09:51

Quote:

Originally Posted by SD1too

When you’re stationary in traffic, does the temperature slowly rise to 104 degrees (with air conditioning off)?

Simon

Hi pal,yes it does very slowly but fan not kicking in at 104.air con fan working though

Yorkshire GOC · 1st August 2018, 19:08

Sounds like your fan has failed - it should engage at 104 and bring the temp down to 92 - have you done the demist test to see if the fan is working ie select the demist button and go to front of car to see if fan is working?

If it has failed the fix will be dictated by whether you have a 2 speed or 3 speed fan.

Look through your front grill RHS and you will see the fan - if it is a 2 speed it will have either a silver or gold resistor ( 3 inch oblong in size and shape at 2 o'clock on the fan) - the original silver resistor is a classic known failure point on a 2 speed fan and folk replace it with the newer upgraded gold resistor. Cheap and easy fix.

So best to see what fan you have first. I think a 3 speed can be more problematic ie bushes knackered for example.

johnpilky · 1st August 2018, 19:33

Quote:

Originally Posted by Yorkshire GOC

Sounds like your fan has failed - it should engage at 104 and bring the temp down to 92 - have you done the demist test to see if the fan is working ie select the demist button and go to front of car to see if fan is working?

If it has failed the fix will be dictated by whether you have a 2 speed or 3 speed fan.

Look through your front grill RHS and you will see the fan - if it is a 2 speed it will have either a silver or gold resistor ( 3 inch oblong in size and shape at 2 o'clock on the fan) - the original silver resistor is a classic known failure point on a 2 speed fan and folk replace it with the newer upgraded gold resistor. Cheap and easy fix.

So best to see what fan you have first. I think a 3 speed can be more problematic ie bushes knackered for example.

two speed fan fitted uprated resistor fitted ten years ago fan working ok

Yorkshire GOC · 1st August 2018, 19:44

Well if its not kicking in at 104 then it is not working properly - it should bring you down to 92 when you get stuck in traffic etc ECU/sensor fault?

johnpilky · 2nd August 2018, 08:04

Quote:

Originally Posted by Yorkshire GOC

Well if its not kicking in at 104 then it is not working properly - it should bring you down to 92 when you get stuck in traffic etc ECU/sensor fault?

Fan kicking in at 106/108

T-Cut · 2nd August 2018, 09:04

I'm told the KV6 2-speed system trips low speed at 112C, (though 106/108C seems preferable), so only the lack of hose pressurisation seems abnormal.

How are you testing 'pressurisation'?
Is the pressure cap in working order?

TC

31st July 2018, 19:54	#1
johnpilky Loves to post mg zt 160+ Join Date: Jun 2009 Location: wigan Posts: 398 Thanks: 55 Thanked 14 Times in 12 Posts	top hose not pressurising when engine up to temperature hi,top hose not pressurissing when engine up to temperature any ideas thanks

31st July 2018, 20:08	#2
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: 20,530 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	What is the engine’s normal running temperature John? Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

1st August 2018, 07:05	#4
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: 20,530 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	When you’re stationary in traffic, does the temperature slowly rise to 104 degrees (with air conditioning off)? Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

1st August 2018, 19:08	#6
Yorkshire GOC I really should get out more....... Rover 75 connoisseur se v6 auto Join Date: May 2014 Location: Hull Posts: 2,085 Thanks: 1,842 Thanked 623 Times in 469 Posts	Sounds like your fan has failed - it should engage at 104 and bring the temp down to 92 - have you done the demist test to see if the fan is working ie select the demist button and go to front of car to see if fan is working? If it has failed the fix will be dictated by whether you have a 2 speed or 3 speed fan. Look through your front grill RHS and you will see the fan - if it is a 2 speed it will have either a silver or gold resistor ( 3 inch oblong in size and shape at 2 o'clock on the fan) - the original silver resistor is a classic known failure point on a 2 speed fan and folk replace it with the newer upgraded gold resistor. Cheap and easy fix. So best to see what fan you have first. I think a 3 speed can be more problematic ie bushes knackered for example. __________________ She came off the Longbridge Line on 20-05-2003 The Silver Machine was the 13th of 160 Rover 75's to come off the production line that day and is the 100th of 527 Starlight Silver Rover 75 2.5 V6 Connoisseur SE Auto saloons listed in the build records produced world wide. Last edited by Yorkshire GOC; 1st August 2018 at 19:10..

1st August 2018, 19:44	#8
Yorkshire GOC I really should get out more....... Rover 75 connoisseur se v6 auto Join Date: May 2014 Location: Hull Posts: 2,085 Thanks: 1,842 Thanked 623 Times in 469 Posts	Well if its not kicking in at 104 then it is not working properly - it should bring you down to 92 when you get stuck in traffic etc ECU/sensor fault? __________________ She came off the Longbridge Line on 20-05-2003 The Silver Machine was the 13th of 160 Rover 75's to come off the production line that day and is the 100th of 527 Starlight Silver Rover 75 2.5 V6 Connoisseur SE Auto saloons listed in the build records produced world wide.

2nd August 2018, 09:04	#10
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,754 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	I'm told the KV6 2-speed system trips low speed at 112C, (though 106/108C seems preferable), so only the lack of hose pressurisation seems abnormal. How are you testing 'pressurisation'? Is the pressure cap in working order? TC