Osakakev Posted August 31, 2022 Share Posted August 31, 2022 Hi, I had a radiator change with new rap cap in early July and it started overheating when I got it back. It turned out to be an airlock which mechanic cleared and all had been fine for nearly 2 months. Today the temps were climbing quicker than usual at idle and heater is luke warm. The max it gets at warn idle is just over 90c and the fan kicks in but then stays on it doesn't reduce. The stock temp gauge goes from its usual quarter mark to half way. Could this be an airlock still or thermostat? Coolant reservoir is full. My amp has recently started blowing fuses, I'm sure it's not related just thought I'd say! Car is 06 Rev Up Thank you Quote Link to comment Share on other sites More sharing options...
davey_83 Posted September 1, 2022 Share Posted September 1, 2022 I would say it's an air lock in the system. Coolant bleeding needs to be done while the heaters are on to make sure coolant is allowed to flow via the heater matrix. Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 Thanks Davey. I'm fairly sure the heaters were working after it was re-bled the first time and the fans were definitely kicking and going off once cooled down as normal so it's only happened in the last day or so (car is used daily). Could a small air lock reappear in the system or not be noticed for a while? One thing I haven't checked is coolant level in radiator but expansion tank is full Quote Link to comment Share on other sites More sharing options...
Zalas Posted September 1, 2022 Share Posted September 1, 2022 Full expansion tank? Full to line/marker or full to brim? Expansion tank should expand when hot and then reduce when cool/cold - if it's staying pressurised it would suggest head gasket (pressurised by exhaust gasses). Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 It's just under the full mark. It's always moved slightly from hot to cold but nothing big (not sure if this is normal). Sorry not sure what you mean by staying pressurised? Don't know massive amount about cars tbh Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 I'm definitely not losing any coolant out of the reservoir tank (i.e. it's not bubbling over) I do loose a bit from the temp adaptor but minimal and probably just needs tightening up (it's new along with the hoses) Quote Link to comment Share on other sites More sharing options...
Zalas Posted September 1, 2022 Share Posted September 1, 2022 Panic over on that one then You'd notice. Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 Thanks Zalas. So either still a small airlock or thermostat. Would upgrading the radiator and leaving stock (assume from 2006) thermostat cause this? Quote Link to comment Share on other sites More sharing options...
mr v6 Posted September 1, 2022 Share Posted September 1, 2022 Best to get the front of the car high up on axle stands too, this helps the bleeding process a lot, so do those bleeding systems with a bucket & adapters you fit to the radiator where you fill it. Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 Cheers, might give it to a different garage to sort as don't have any axle stands Checked and radiator also full Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 Just some more info; Heater is super hot when driving on motorway but gets colder the slower I go and the temps rise. The aftermarket sensor (cut into top radiator hose) does not seem to be giving correct readings anymore. It goes to max 90c but fan is already on which was not the case before. (Used to come on at 95c. The stock temp gauge also goes to the middle when idle for a while but aftermarket is still at 90c (in theory this should be higher as got to 90c regularly before whilst staying at quarter mark). Hope this makes sense lol Quote Link to comment Share on other sites More sharing options...
Zalas Posted September 1, 2022 Share Posted September 1, 2022 6 hours ago, Osakakev said: Thanks Zalas. So either still a small airlock or thermostat. Would upgrading the radiator and leaving stock (assume from 2006) thermostat cause this? No, shouldn't do. Tstat opens and closes regardless of rad unless you've got something dislodged and stuck in the tstat from the flushing and refilling? Quote Link to comment Share on other sites More sharing options...
Osakakev Posted September 1, 2022 Author Share Posted September 1, 2022 I know the nismo opens earlier so thought newer and bigger radiator might need that. Yes could be but strange it's 6/7 weeks afterwards Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.