Scottish Elises

was stopped at traffic lights when i noticed steam coming from bonnet.
stopped and checked water and it has went down to the min. it usually sits at 3/4. i've only had the car 3 months and done 1500 miles problem free. any ideas?? im utterly clueless.

Could just be rainwater evaporating from the rad - and min level on the expansion tank could be normal.

Sniff the steam if you're still worried, sweet smell of coolant would be bad...

Water is supposed to be at min when running (should read 'hot') as the system pressurises - look at it cold and I'll bet it's back up to where it usually is.

The steam is rainwater running onto the top of the rad core when it's hot. Scares the crap out of you first time it does it in a rainstorm and makes sitting in traffic fun, as everyone thinks you're overheating!

Water is supposed to be at min when running (should read 'hot') as the system pressurises - look at it cold and I'll bet it's back up to where it usually is.

The steam is rainwater running onto the top of the rad core when it's hot. Scares the crap out of you first time it does it in a rainstorm and makes sitting in traffic fun, as everyone thinks you're overheating!

im letting the car cool the now so will check the level. it had been raining heavy so it does sound like it could be this.

mainsy wrote:

Water is supposed to be at min when running (should read 'hot') as the system pressurises - look at it cold and I'll bet it's back up to where it usually is.

The steam is rainwater running onto the top of the rad core when it's hot. Scares the crap out of you first time it does it in a rainstorm and makes sitting in traffic fun, as everyone thinks you're overheating!

im letting the car cool the now so will check the level. it had been raining heavy so it does sound like it could be this.

Just (carefully) loosen the cap. Will release the pressure.

Happens to all new Lotus drivers...

I crapped it when steam first appeared on mine...

X7LDA wrote:Happens to all new Lotus drivers...

I crapped it when steam first appeared on mine...

Had the exact same paranoia with mine to start with. Steam out the front combined with the coolant sitting at min level. Just another case of TADTS

BUT:-

The MIN level is for when the coolant is COLD.

The MAX level is for when the coolant is HOT.

Someone will pipe up in a moment and say that their's works differently - i.e. the level drops when hot and returns when cold - they have something wrong with their coolant system, most likely an airlock.

The only air in the (properly filled and working) system lives in the tank above the coolant. As the coolant gets hot, it expands and compresses the air, thus the level rises.

The pressure relief valve in the cap fails frequently (on some cars it can fail once a year it seems); in this case the level will drop slowly as some vapour is lost along with excess pressure as the cap vents (tell tale snail trail down the expansion bottle from the cap to the seam).

Different cars find different COLD/HOT levels, usually due to weeping pressure relief caps, though also just due to subtle differences in system volume I would guess.

Provided your COLD level remains steady and visible in the tank (i.e. check it once a week), there is no need to top it up. If you find it's dropping below the empty level of the tank, then you have a leak.

So your level may be dropping due to a leak, or weak pressure relief valve, or may just be finding its natural level after being topped up.

Your steam may just be rain water running onto the radiator.

Cheers,
Robin

hi,

we have an S1 also,

yes you will get steam coming from the rad, ours seems to start at the driver side and work its way across to the passenger side as the rad heats.

the fluid level might have dropped if the was air in the pipes or rad and the thermostat opened thus opening the rad fully and the air moved out. The way to check for air os to put your hand in the bonnet toweards the toip of the front wheel you will find the rad pipe, on the top is the bleed screw which you should be able o open with your fingers, it will hiss if there is air and water sill come out of it is full, do it when the engine is running to give it pressure and check again once the engine is above 88 deg so as to ensure the stat has opened.

As others have said as long as it doesn't keep dropping you are fine.

Add some anti-freeze rather than water as this stops it freezing in the winter, if it keeps leaking check the pipe connections at each side of the rad., as this is where ours leaked as the pipe on the passenger side was loose. ( has probably been like that since built and since we got the car )