Constant Thermostat Failures!

Discussion in 'Engine, Gearbox, Exhaust and Air Intake' started by suj, Aug 10, 2017.

  1. Timbo

    Timbo

    Messages:
    70
    Car:
    Clio Sport 200 Cup Trophee
    Maybe get an OBD tool to determine the temperature at which it cuts in first. Should be 90C and if that's what's happening, it's not a stat problem (indeed, if there's no other cooling problem, a broken stat is most likely to have the car running too cool more often than not. That said, it seems these Renault 70C stats have a life of c.5-7 years. If you change it, it's also worth doing a full coolant flush and change.
     
    Paul222 likes this.

  2. Paul222

    Paul222 Gold Member

    Messages:
    30
    Location:
    Truro, Cornwall
    Car:
    Clio F1
    Ideal thanks for the information. I'll look into doing that. Sorry for hijacking the thread
     
  3. A1axx

    A1axx

    Messages:
    480
    Location:
    Wiltshire
    Car:
    Clio 197 Race Car
    It's a 75 degree stat because the rad is tiny. I'm fitting a meg rad with the conversion, it's so much bigger!

    So it's constantly flowing coolant through with the 75 degree one.


    Sent from my iPhone using Tapatalk
     
  4. Doogle

    Doogle Winner - POTM March 2018 Paid Member

    Messages:
    605
    Location:
    Plymouth
    Car:
    BMW e46 330cd
    Sorry for hijacking an old thread, I have thermostat issues. When I bought my car almost a year ago the stat was knackered, in between first and 2nd line. Had it changed last year but this winter killed it. It would fluctuate between 2nd and 3rd, Torque Lite said its sitting around 68-72 so not awful. In colder weather (4 degrees or lower) it seemed to struggle to get above 65. Garage changed it and said its the same, now with slightly warmer weather it sits nearer to the 3rd line. As the dash temp gauges this will only be 75-80ish. I have NEVER seen it hit the 3rd line, and I sit in traffic all the time. It doesnt seem right to keep it cool all the time? You would get hot and cold parts, hot spots, and oil is designed to work best over 90 degrees.

    Has anyone fitted a 182 stat? Its not like it gets hot in the UK!
     
  5. suj

    suj Gold Member

    Messages:
    703
    Location:
    Birmingham / Warwick
    Car:
    Nimbus Grey 197
    So I used to think mine was broken, but it wasn't.
    It's meant to fluctuate between 2nd and 3rd line, as the third line to the middle-ish is about 80-95 degrees (give or take) so it's not ideal as the guage doesn't read super accurate.

    It's a 75 degree stat, so while moving it was at 75, then it will go to 76-77 and open and drop down to like 72, then repeat. 90 degree stats do exactly the same, but as they go from 92>85ish (like I said earlier, in the central range) you wouldn't see the needle move so much or at all.

    Also the fans kick in at like 90 degrees, so that is why when stationary it will peak higher, so that again is normal.

    I had come from cars with 90 degree stats, so this was new to me.

    I bought a genuine one and it's been fine since, I have logged my temperature for many many miles (paranoia).

    Renault designed the engines to run 75 degree stats for a reason, I wouldn't put a 182 90degree stat on, I think I'd trust Renault over a few people who have put the higher temperature stats on lol.
     
    petercronin likes this.
  6. RSRowe

    RSRowe Paid Member

    Messages:
    32
    Car:
    Clio 197
    So kids. Bit of a thread rekindle here....... Currently having a discussion with someone on Facebook:

    Screenshot_20181010-191018_Facebook.jpg

    So what's best.....
    Is the 90 best because of what this lad says? Or is a 75 one best because that's what's fitted standard?
     
  7. temeeo

    temeeo Gold Member

    Messages:
    18
    Location:
    Dublin
    Car:
    Clio RS 197, Mitsubishi FTO
    Go with stock thermostat, it only starts opening at 75 and ends (is fully open) at 87 on the F4R 830/832, I'm sure there must be a reason for it! Most of other Mk III engines us thermostats that open at 89 but they don't have engine bays as packed as the RS

    The part number is 8200772994
     
    RSRowe likes this.
  8. suj

    suj Gold Member

    Messages:
    703
    Location:
    Birmingham / Warwick
    Car:
    Nimbus Grey 197
    It was designed to run lower to make power, you are right it might get you better MPG on a 89degree stat, but won't be as responsive regardless of what people say.

    Like me, it was the first time I had such a low stat, so it was daunting in my first winter seeing the needle move about, but after researching it is fine. My BMW 740iL had an electronic stat that worked way past 90 degrees on a cruise for better MPG so that was odd too!

    Also you do track days, so I think it makes sense alone to get the lower stat (the M├ęgane engine lot use these stats on their track cars for example).
     
  9. Doogle

    Doogle Winner - POTM March 2018 Paid Member

    Messages:
    605
    Location:
    Plymouth
    Car:
    BMW e46 330cd
    I know it will retard the timing when its too hot, losing power and making it run hot. However, what I have found is in the winter even a thermostat only 6-12 months old is not strong enough to run at a decent temp for normal driving. Last winter I saw temps of 65 degrees at times when it was cold when commuting. That just seems a waste to me and if a 90 degree stat from Renault is just as sh*t it will run cooler than it should.

    It depends how you drive. Driving hard a 90 degree stat makes no sense. Even in normal temps (10-15 degrees - you know you're British when over 15 degrees is hot!) it doesnt make sense with our engine but in winter and for 90% commuting, I can see the relevance, even though Renault fitted a 75 degree stat.

    I plan to try a 90 degree stat, just to try over winter and Ill monitor temps. My car is currently 90% commuting and 10% fun.
     
    suj likes this.
  10. suj

    suj Gold Member

    Messages:
    703
    Location:
    Birmingham / Warwick
    Car:
    Nimbus Grey 197
    This is exactly what I was thinking the other day, now the temps have dropped in the morning to 2-3degrees when I go work, it has been sitting low.
    So I was considering using a 89degree stat to see how it affects things.
     
  11. Doogle

    Doogle Winner - POTM March 2018 Paid Member

    Messages:
    605
    Location:
    Plymouth
    Car:
    BMW e46 330cd
    Worst case scenario the fan will run more. I doubt its going to overheat and its not a massively expensive part to replace.
     
    suj likes this.
  12. RSRowe

    RSRowe Paid Member

    Messages:
    32
    Car:
    Clio 197
    I'm generally only getting between 60-65 daily driving.
    Which is what's led me to believe mines stuck open
     
  13. suj

    suj Gold Member

    Messages:
    703
    Location:
    Birmingham / Warwick
    Car:
    Nimbus Grey 197
    It could well be, mine drops down to about 70 (now it's cold), but never that low, buy genuine from @renaultpartsdirect I bought a Gates one, it failed straight away, then had a genuine one in and it's been bang on since (over a year).
     
    renaultpartsdirect likes this.
  14. RSRowe

    RSRowe Paid Member

    Messages:
    32
    Car:
    Clio 197
    Thanks for the recommendation
     

  • Share This Page


    1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
      By continuing to use this site, you are consenting to our use of cookies.