Sticky thermostat

Ravinder · 23rd March 2018, 22:03

Hi

Since I’ve has my 75 diesel, my thermostat has always been stuck partially open. So, it doesn’t get to temp fully. What’s the best solution to this? New thermostat? Some sort of mod? Is it a straightforward job? And, where am I best getting the relevant parts from? Thanks. Ravinder

klarzy · 23rd March 2018, 22:05

https://the75andztclub.co.uk/forum/s...89&postcount=5

check this thread

T-Cut · 23rd March 2018, 22:10

If you do the in-line mod, ensure you buy a Renault 5, 88-89C stat made by Gates, FirstLine or Wahler. These are known to optimise the running temperature. Other brands may not, due to valve leakage.

TC

Ravinder · 24th March 2018, 08:17

Thanks. So what’s the difference between just replacing the thermostat with a standard 75 one and this in line one that people talk about ?

oldie · 24th March 2018, 08:43

12 hours, half the engine and the possibility the replacement thermostat will also become stuck. In my experience.

EastPete · 24th March 2018, 09:06

Quote:

Originally Posted by oldie

12 hours, half the engine and the possibility the replacement thermostat will also become stuck. In my experience.

I reckon it is about 3 hours work to change the stat properly (ie: replacing the original with a good quality replacement- get one from Rimmers). It is a bit fiddly, with limited access - you have to remove the upper right engine mount and tie bar and support the engine (raising it slightly) whilst you carefully unbolt the thermostat and coolant rail/hose. You have to be careful refitting the coolant rail not to bend it too much, and use a new O-ring. I think Jules posted a 'how-to' on here a while back.

Pete

klarzy · 24th March 2018, 09:40

Quote:

Originally Posted by Ravinder

Thanks. So what’s the difference between just replacing the thermostat with a standard 75 one and this in line one that people talk about ?

the in line stat is 10 mins work where the OEM is several hours.
in future the in line stat is 10 mins to change....

you cut the pipe, put the stat in, do up the jubilee clips and top up the coolant...
the engine will run 9 degrees hotter than OEM which makes it slightly more efficient without doing any harm....

IMHO the only reason to do the OEM stat is if you are replacing the pump at the same time or if the old stat has failed shut...

T-Cut · 24th March 2018, 10:13

There have been one or two reports in recent times that suggest the current/latest/third generation OEM thermostats suffer from the same issue as the most common one (2nd generation). The problem stems from a physical or chemical change in the wax, which causes them to start opening early. They don't stick open or become 'sticky', they simply bleed coolant through the valve at lower and lower temperature until the engine never warms up.

TC

klarzy · 24th March 2018, 13:34

Look what i found in the garage

88C
£35 posted

Mickyboy · 24th March 2018, 16:16

Quote:

Originally Posted by klarzy

Look what i found in the garage

88C
£35 posted

I’ve got one of those in my stores, have mine running at 92° super, prefer this type to any other type. At 92° the engine is far more efficient and also less thermal transfer as it keeps it stable between 90/92 degrees
Mick

23rd March 2018, 22:03	#1
Ravinder This is my second home Rover 75 saloon x2, Rover 75 Tourer x2, Rover 220 Coupe Turbo Join Date: Aug 2010 Location: Kirkcaldy, Fife Posts: 9,036 Thanks: 2,278 Thanked 2,852 Times in 1,718 Posts	Sticky thermostat Hi Since I’ve has my 75 diesel, my thermostat has always been stuck partially open. So, it doesn’t get to temp fully. What’s the best solution to this? New thermostat? Some sort of mod? Is it a straightforward job? And, where am I best getting the relevant parts from? Thanks. Ravinder __________________ Wanted - Indian bride. Cash waiting. (All sorted - bargain) First name and forum name: Ravinder Rover 75 2.0 CDT Connoisseur SE 116 (160 remap) Royal Blue (JFM) This vehicle was the 50,481st 75 to run off the production line, out of 112,381 This vehicle was the 2,238th 75 CDT Connoisseur SE to be made out of 3,775 This vehicle was the 5,002nd 75 in Royal Blue (code: JFM) to be made out of 14,420 Royal Blue 75s

23rd March 2018, 22:05	#2
klarzy This is my second home none but not gone Join Date: Mar 2013 Location: March, Cambs Posts: 16,437 Thanks: 894 Thanked 4,247 Times in 3,025 Posts	https://the75andztclub.co.uk/forum/s...89&postcount=5 check this thread __________________ [SIGPIC][/SIGPIC]….All praise Bananaswan….

24th March 2018, 08:17	#4
Ravinder This is my second home Rover 75 saloon x2, Rover 75 Tourer x2, Rover 220 Coupe Turbo Join Date: Aug 2010 Location: Kirkcaldy, Fife Posts: 9,036 Thanks: 2,278 Thanked 2,852 Times in 1,718 Posts	Thanks. So what’s the difference between just replacing the thermostat with a standard 75 one and this in line one that people talk about ? __________________ Wanted - Indian bride. Cash waiting. (All sorted - bargain) First name and forum name: Ravinder Rover 75 2.0 CDT Connoisseur SE 116 (160 remap) Royal Blue (JFM) This vehicle was the 50,481st 75 to run off the production line, out of 112,381 This vehicle was the 2,238th 75 CDT Connoisseur SE to be made out of 3,775 This vehicle was the 5,002nd 75 in Royal Blue (code: JFM) to be made out of 14,420 Royal Blue 75s

24th March 2018, 13:34	#9
klarzy This is my second home none but not gone Join Date: Mar 2013 Location: March, Cambs Posts: 16,437 Thanks: 894 Thanked 4,247 Times in 3,025 Posts	in line thermostat Look what i found in the garage 88C £35 posted __________________ [SIGPIC][/SIGPIC]….All praise Bananaswan….

23rd March 2018, 22:10	#3
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	If you do the in-line mod, ensure you buy a Renault 5, 88-89C stat made by Gates, FirstLine or Wahler. These are known to optimise the running temperature. Other brands may not, due to valve leakage. TC

24th March 2018, 08:43	#5
oldie Loves to post Connoisseur SE v8 auto '54 Join Date: Jan 2009 Location: West Sussex Posts: 488 Thanks: 105 Thanked 56 Times in 41 Posts	12 hours, half the engine and the possibility the replacement thermostat will also become stuck. In my experience.

24th March 2018, 10:13	#8
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	There have been one or two reports in recent times that suggest the current/latest/third generation OEM thermostats suffer from the same issue as the most common one (2nd generation). The problem stems from a physical or chemical change in the wax, which causes them to start opening early. They don't stick open or become 'sticky', they simply bleed coolant through the valve at lower and lower temperature until the engine never warms up. TC