Arrrr well I took my elise with vhpd engine in for a spin today and noticed the temp gauge behaving very stange. It has a 70deg stat in and the temp norm site around 79deg while driving norm. well today it was sat about 85deg and as soon as I gave the car any stick it shot into the 90s!! and u could hear the fans on the rad kick in while still driving along!!! Also I noticed that the heaters 1 min would be blowing warmish and next be blowing hot like it does normaly! Also if I stopped for any reason the temp would saw up fans kick in but temp still went straight up! I would then take it around the block to cool down and them temp would drop to low 70s straight away!!! When I pulled up I popped the bonnet with the fans kicking in as temp was showing over 95deg and the rad felt cold! I tried opening the bleed valves a little and there was no air escaping and it didnt help the problem.
What could it be?
Headgasket?
Airblock?
Faulty stat?
I think it’s an airlock.
Now, why you have an airlock is another issue.
But I would start by topping and purging the system (pressurized) and see if the problem persists.
If it goes away, just see where the coolant is going to allow you to have another airlock.
I dont think it can be the temp sensor as its a new sensor and also the fans r kicking in while moving which run off another sensor,
Oh well if it is the head gasket do I need to get the head skimmed? is it a job I can do myself or should I take it to a garge? how about other things like the cambelt etc thats quite new!
As Randy says, not a hard job, just take your time. I did mine with the clam on, and you do spend a fair bit of time with your head in the wheelarch, when doing the cam belt etc.
Well I went out to the car this morning and pressurised the coolant system, opened the bleed nipples and I could hear air coming from them both. Once water passed through I closed them and took the car for a spin. Everything seemed fine while it warmed up so I went onto the bypass and gave it some stick, again no overheating problems, had my laptop plugged in at the same time so could watch both the coolant temps. Got back to the garage and let the car idle, watched the temps creep upto 98deg fans kick in and temps drop to 92deg like it used to. So looks like the problem is sorted for now! But why did I get all this air in my coolant system? Could the HG still of failed and pumping air into the system?
The symptoms you are having are exactly what I had and I will be very suprised if it doesn’t end in HGF. Take it for a hard blast, try sticking it in 3rd and pulling all the way through the revs. When you get back in I bet you will have air in the system again.
Hmmm, did you do a trackday or anything recently where water pressue would be right up there? Normally air can only get in via a HGF or a leak…
…Mine weeps slightly from the rubber hose attached to the ali pipe from the left hand side chassis rail just as it enters the engine bay… When I finally get round to putting the PRRT on that should sort it