Is it getting too hot?

[lisbon_road]

Not sure if my car is getting too hot.

 

Mk3 Astra, temperature gauge has markings for 90 deg c and 100 deg c and goes red above that.  I know the weather is hot but it does seem to shoot up and was getting close to the 100 when going down the motorway yesterday evening at moderate speed.  I am sure it didn't used to do this.  I checked the thermostat recently which opened nicely in a pan of hot water. 

 

Runs smooth, gave 52 mpg yesterday so no problem there.  I realise that temperature gauges are totally uncalibrated and so on.

 

Any comments? 

[Sigmund Fraud]

Surely, the Autoshite way is "don't worry about it"*.

 

*until the engine reaches such high temperature so as to cause the infamous China syndrome !

[lisbon_road]

I've just put new rings in it as compression had dropped which might (or might not) be due to having ignored this for too long so ....er...not too keen to ignore it now......

[wuvvum]

The Cavalier's temperature gauge doesn't work.  Problem solved.

[EssDeeWon]

You could always test the cooling system by popping into Central London this afternoon for a cruise around the West End for an hour, that will firm things up nicely.

[Junkman]

As long as the gauge is not in the red, everything is perfectly fine.

[EssDeeWon]

...and when it does go in the red everything is still perfectly fine until steam is coming out.

[dollywobbler]

  On 04/07/2014 at 13:48, EssDeeWon said:

...and when it does go in the red everything is still perfectly fine until steam is coming out.

 

That's where I'm at with the Maestro! Gauge not in the red, so ignore flashing red light of doom until something bad happens. 

 

Does sound like this Astra isn't cooling itself very well. Could try running your hand over the rad to see if there are any cold bits suggesting it has silted up. 

[Angrydicky]

My Maestro seems to run on the cool side as it happens (just to rub it in).

[Squire_Dawson]

I'm not sure about the nuances of Vauxhalls, but if it's getting close to boiling point when motorway driving then I myself would be concerned. Check the radiator fins for corrosion and if the car isn't often used or coolant regularly changed then a hosepipe flushing through the waterways of the block and rad will hopefully sort things out or show up the possible problem.

 

Cars I have had in the past normally sit around 70-80 deg. C

[lisbon_road]

The radiator is nearly new.  It gets hot so I suppose that rules out the water pump, something like impeller fallen off.  But I think the idea of checking the rad for cold areas is really good.

 

Thanks.

[Squire_Dawson]

Just had another idea, though probably an unlikely one, that the new rings might be causing a lot of friction leading to more heat than normal?

[xtriple]

When an engine has just been rebuilt they do tend to run hotter as there is more friction. How long ago did the new rings go in and were they OEM or ridge dodgers?

[Dave_Q]

Close to 100 is probably fine, does the fan kick in?

 

I'd be in the 'don't worry about it' camp, as long as it stays out of the red WCPGW?

[Stixy]

Was it a genuine rad or aftermarket  ?  ive noticed with a lot of aftermarket rads you get a lot thinner core 

 

Any change in behavior on an older car is worth looking into   but as long as the fans are cutting in as they should you shouldnt have a problem .

 

But i know how you feel i watch my temp gauge very closely  and have an overide switch inside the car to turn the fans on if needed and incase the  temp switch fails 

[Bren]

All vauxhalls are shit etc....

[rml2345]

As long as it levels out before the red and the fan kicks in I'd be inclined to leave it be and see if it gets worse.

Could it be a dodgy temp sender?

[Rusty_Rocket]

What engine is in this Astra? The x16/z16 always used to (apparently) run quite warm; shooting up to just below the red before the fan kicked in. As long as the fan is coming on and returning the gauge to just under 90, everything is fine.

Incidentally, running an engine like the small-block Ecotec at this temperature is best for fuel economy and bore wear. 

[lisbon_road]

It is a C14SE.

 

The rings have done hardly any miles at all.  But it was doing the same before they were fitted - and they went in fine, and the engine would turn over easily.  Gaps looked healthy. 

 

Could it be a dodgy sensor?  Yes, it could.  I think I have a spare one in the car so perhaps thats the first thing to try as quick and easy.

 

The radiator is aftermarket from Eurocarparts, ridiculously cheap on one of their sales.  Could it be the problem?  Yes - it certainly could. 

 

Thanks for the replies..........

[DaveAspley]

When I worked at Vauxhall it was a complaint along with the Cavalier Mk3. They apparently have a 110 degree thermostat if memory serves me right. As long as the fan cuts in and out and it doesn't go into the red then you're fine. You'll probably find it barely warms up in the winter too. Diesels especially bad for this as the radiators were too big.

[DaveAspley]

I had a j reg c14se astra saloon. Exact same behaviour

[Stixy]

/\   Fit a diesel rad 

[DaveAspley]

Iirc the same part. Don't forget, the cooling system being under pressure reduces it's boiling point hence 100+ degrees at 15psi is like 70 degrees (I think!)

[lisbon_road]

I have had it run sensibly at what looks like about 93 in a totally uncalibrated gauge.  I converted it from the spi (yeuk) to the mpi (much more power if not exactly a fireball and +8 mpg) and it ran fine but something has gone amiss since.

 

Tomorrow I will swap the sensor first, then perhaps the rad and water pump and thermostat as all are on the shelf somewhere.  I know it sounds a lot but I have done this so many times now I can probably do the water pump and thermostat in an hour.

[DaveAspley]

Sounds perfectly fine. Totally within spec.

[richardmorris]

I'm paranoid about engine temp - try owning an x1/9! Anway, had a word with my new merc. mechanic guy on Wednesday when he was doing my discs and talked to him about the temp which had concerned me in the queue to beaulieu in May. He said that the thermostat is fully open at 90 and that it is quite likely to get to 100 in standing traffic with the viscous fan only - I had assumed it had two speeds, but he says not, just locks up. He said it seemed to be working fine, and far too fast to try and stop by hand (test to check resistance).

 

This is the first car I have with a viscous fan - all the others have electric ones to which I have fitted a manual override switch (2cv excepted of course).

 

I'd keep and eye on it and see if the behaviour changes.

[DaveAspley]

Try a v8 e39 5 series. 120 thermostat! The under bonnet heat is unreal. Chucked all the sound deadening, crap viscous fan, plastic tat in front of the rad, all the a/c went in the bin anyway so that was a bonus. Stuck a 22 quid eBay fan kit on and it now doesn't melt under pressure.

[Split_Pin]

With those old VX guages it should run just above or just below the first mark above 90. The fan should kick in somewhere in the middle.I had a Corsa with the same engine.

 

Is the coolant circulating in the header tank?

 

 

When driving from cold, the guage should rise slowly to just above the first mark above 90, nd then drop quickly to 90 as the thermostat opens. It should then rise again to around that mark and under normal driving shouldn't really move that much.

[mrbenn]

My Dad has a 1.6 Ecotec Astra a while ago and I remember the gauge used to get very high on that before the fan came in and brought it back down.

[Wilko220]

The one thing that annoyed me about my 75 was that it had a temp gauge which, once up to temperature, didn't move (unless the engine was overheating). Some kind of computer controlled bullshit. What the fuck is the point of having a temp gauge if it doesn't actually show you the engine temperature?