The coolant temperature gauge on my RS250 always sits below center so I am assuming it's a sticky thermostat. No obvious knock on issues though. I have changed one on my old e36 m3 and it was an ok job and I am fairly competent with the spanners, but the Megane engine bay seems tiny with little room to work. Any opinions on if this is best left to a specialist or is it worth DIYing? Are there other jobs that it makes sense to do at the same time?
I'm sure this is normal on the rs 250, I'm sure i've read a post that said the rs250 sits just below half and the rs265 sits bang on half. I'm sure someone will come along and confirm. Are you having temp issues? or was it always at half before but now isn't etc?
It’s not a hard job it’s just fiddly. The bottom bolt is a pain in the ass to get too. Sitting under half way is fine on the 250
However If you do replace it I believe a decent aftermarket one is better than Renaults version. One way to find out is if you wait for the car to be at temp and go for a blast and try and redline the car. If the limiter kicks in too early you need to change the stat, if not and you have no other issues its fine.
Thats correct 250 sits under the half way line, 265 sits bang on the line. Just be aware that there is a strong chance that you will get air in the radiator, the only real way to get the air out is to remove the front bumper. The hoses are only 2/3rds of the way up the rad and with no top pipe any air will stay in the rad. There is a bleed on the top of the rad but its hidden by the bumper.
I did mine DIY. Access is not great at all and I had to remove battery tray etc. It was very fiddly but I managed, just take your time. My temp was sat just below half and I was unable to Rev past 5.5k. Changed for an OE stat and was able to rev engine out when warm.
Also obviously had to bleed system after, I didn’t lose much coolant but you will still need to top up a tad. Mine bled okay with expansion tank cap off and heaters on, I’ve heard some struggle though. FYI I own a 265.
Thanks for the replies everyone. The car does rev all the way to the redline and has no other issues. If that is the normal position then that's fine and it is reassuring. I assume you can plug in a cheap ODBC reader to get the actual coolant temperature for a more accurate check?
