Temperature climbing quite quickly when idle

[TophaTron]

Hi,

I have a quirk with my Elise S2 K that's happened since I changed the radiator.

Basically, the temperature seems to climb quite quickly up to about 95/96 when the car is sitting idle, quite a bit quicker than it used to. While driving the temperature is normal - around 90.

However if I'm stationary and hold the revs at about 2k, it doesn't heat up as quickly and stays around the 91/92 mark.

I bled the system through after I installed the rad, does this indicate I might need to again?

Cheers for any advice!

Chris

[BiggestNizzy]

I wouldn't be worried.

when you are running at 2k the water pump is running faster moving more water., keeping the engine cooler.

[TophaTron]

I wouldn't be worried.

when you are running at 2k the water pump is running faster moving more water., keeping the engine cooler.

Thanks for the reply. My main worry is that the behavior is now different to how it was pre radiator change. Is it possible there is a slight air lock, which is bypassed when the pump is running quicker?

[BiggestNizzy]

It just sounds really normal to me.

[roadboy]

There's still air in the system. Air pockets give the impression of poor water pump performance.

Give it a good bleeding and it should be fine.

Dan

[robin]

It might help to adjust the angle of the car whilst bleeding so that air in the radiator can actually escape to the forward bleed valve.

Mine is in much the same state - haven't been arsed to sort it yet.

Cheers,
Robin

[TophaTron]

Thanks for the replies. Apart from getting the car at an angle, is there any other tips to getting it to bleed properly? High/low rpm? When the engine is at a certain temp?

[robin]

Assuming you are using the standard thermostat and not the PRT then both the rad and engine bay bleed points are always under pressure when the engine is running. A fast idle certainly helps - Bob showed me a trick with a tie wrap - open the throttle far enough to stick the tongue of a tie wrap between the throttle and the end stop; this causes about 1,500 RPM engine speed which is good for bleeding.

Start from cold to give yourself maximum time to bleed out air before being scolded

Cheers,
Robin

P.S. Not 100% sure of best bleeding procedure if using PRT - the bypass flow is much stronger with a PRT so not sure if more revs/heat required before the PRT directs enough flow to the rad.

[tut]

As per Robin, correct angle means nose higher than rear.

tut

[robin]

As per Robin, correct angle means nose higher than rear.

tut

Actually that depends on where the radiator pipe with the bleed nipple exits the radiator and on the S2 it's not always where you think it's going to be ...

Cheers,
Robin

[steviej]

After changing the cylinder head and exhaust on my S2 last year I refilled the cooling system and ran it up with the rear still up on stands, no issues with air in the system and havnt needed to add any coolant since, maybe luck but I thought that the higher the header bottle was the better for the air bleeding its own way out ?

[robin]

After changing the cylinder head and exhaust on my S2 last year I refilled the cooling system and ran it up with the rear still up on stands, no issues with air in the system and havnt needed to add any coolant since, maybe luck but I thought that the higher the header bottle was the better for the air bleeding its own way out ?

If the car was up in the air when you drained it then the radiator won't have got any air in it. Once you have air in the radiator then a small amount of angle can help persuade the air to come out of the radiator and into the bleed valve ... the higher you make the rear the more entrenched the air will become in the corner of the radiator, except, of course, if your bleed valve is on the pipe that is at the rear of the radiator ....

Cheers,
Robin

[steviej]

That probably explains it then as it was in the same 'rear in the air' position throughout.

[tut]

It used to be so easy, S1's all the same on a basic level.

tut

As per Robin, correct angle means nose higher than rear.

tut

Actually that depends on where the radiator pipe with the bleed nipple exits the radiator and on the S2 it's not always where you think it's going to be ...

Cheers,
Robin