Running hot problems

[Tom_1569]

The ute seems to run a little to hot, cold weather it sits at a 1/4, but as soon as your in traffic, it sits at half way and above (to the next little line) where the thermo cuts in, but takes no more then 20 seconds for it to get that hot, its very quick.

Yesterday in the hot weather it sat just under half on the highway, and would get hotter if air-con was on.
It doesnt go past that little line above half way, so its not exactly over-heating, but Im not comfortable with it running that hot all the time.

So far the following has been replaced:
Radiator hoses, heater tap and core.
Genuine Coolant
New radiator (got worse, but old radiator was cracked)

Next on the list is Thermostat,
Confirm thermo cuts in at appropriate times (can someone tell me when its suppose to cut in)
Water Pump
A better radiator.

Any ideas, help?

[RATTLEHEAD88]

maybe a water jacket is partially blocked in the heads or block.

[Vee-ard]

Thermo cuts in at whatever spec thermo you buy.

You can get 88 deg. Celcius right through to 93 deg. easily

A reverse flush of the block is in order I would say.

[hako]

The theory is that a 82 deg thermostat begins to open at 82 deg......it will be fully open as the engine fully heats up but can be anything from closed (going down a long hill) or fully open (climbing the hill) and anywhere in between. It will constantly vary the size of it's opening depending on how hot the coolant in the block is. You can test it in a saucepan.
Commodores are designed to run rather hot - it's all to do with efficiency....so maybe what you are experiencing is normal.
Thermostats can test OK in a saucepan but when installed can be slow to react or stick and it's always possible for one to be faulty straight out of the box.

[Tom_1569]

maybe a water jacket is partially blocked in the heads or block.

That did cross my mind, but if thats the case, it can stay like it lol.

Thermo cuts in at whatever spec thermo you buy.

You can get 88 deg. Celcius right through to 93 deg. easily

A reverse flush of the block is in order I would say.

Reverse flush has been done.

The theory is that a 82 deg thermostat begins to open at 82 deg......it will be fully open as the engine fully heats up but can be anything from closed (going down a long hill) or fully open (climbing the hill) and anywhere in between. It will constantly vary the size of it's opening depending on how hot the coolant in the block is. You can test it in a saucepan.
Commodores are designed to run rather hot - it's all to do with efficiency....so maybe what you are experiencing is normal.
Thermostats can test OK in a saucepan but when installed can be slow to react or stick and it's always possible for one to be faulty straight out of the box.

Sorry, I meant what temps the Thermo fan comes in, not thermostat, I use genuine Thermostats, and its going to be replaced when I have time as I have a brand new one sitting here.

[Tom_1569]

Also, I noticed if I put the Aircon on before it gets hot it will run very cool in traffic and wont get near half. Yet if I put Aircon on, on the highway it sits just under halfway.

[linz]

sounds alot like what my car it doing atm and i have already replaced the thurmostat and flushed everything at the same time and new coolent but still dose the same thing.

[old mate]

i find my ute runs warmer in traffic, but the thermo fan does its job well so i dont worry about it. all the vs's i've been in seem to run warm in town, not sure on highway.

might be just how they are.

mine runs too cold on the highway, i think a new thermostat is in order.

[Tom_1569]

i find my ute runs warmer in traffic, but the thermo fan does its job well so i dont worry about it. all the vs's i've been in seem to run warm in town, not sure on highway.

might be just how they are.

mine runs too cold on the highway, i think a new thermostat is in order.

Yeah thats quite possible to, just doesnt seem right to me. The VT doesnt get as hot, and its pretty much the same running gear engine wise, just the VT has different cooling system.

[Not_An_Abba_Fan]

I had a VS for 5 years and what you describe is how mine ran. They run about 1/3 to 1/2 on the gauge, it's normal. VS gauges are not known to be terribly accurate either, they are just a guide. Maybe get a proper temp gauge and see what temp the coolant is actually at. But it sounds like a normal VS to me.

[Vee-ard]

I think thats what the majority of people need to understand. On commodores, half way on the temp guage is pretty much normal. 3/4 is when I would would start eyeing it.

I had a stuck open thermostat that sat on the second line (just under a quarter) on the temp guage. This is NOT where you want your temp guage to sit.

[VS_WPN]

This is normal. Buying a cooler thermostat, bigger radiator, cai, heat shields, manifold insulators, plenum spacer ...etc will help.

The reason why it runs cooler with the air con on is when you turn the aircon on the thermo fans are always on, whereas normally it waits till it gets to passed 1/2 then fan kicks in. The dampner for the engine heat shown on the gauge in the VS's are very sensitive (I'm sure there's a better way of saying that) then the other ecotecs. The vt - vy may cool faster because they have 2 thermo fans. Still this behaviour is normal. On a vt - vy the guage wont move as much but im sure its running the same temp as the vs so no need to worry

[andrew270681]

My Vr senator does the same thing. I dont like my gauge going all the way to 3/4.

I have changed my radiator, thermostat and flushed my system.

From what ive read on this forum some people say its normal and some people have never seen their gauge go up to the 3/4 mark...

Im keeping an eye on mine

[Tom_1569]

Hmm, I think Ill just have to accept its normal, as bizaare as it seems to me.
I might grab a water temp gauge at some point (bonnet or A-pillar mount? ) and see exactly what temps its running.

[andrew270681]

I changed my gauge sender and tried a new gauge and i still am running at half way, when i start giving the car a hard time or i hold the revs at 2500 in neutral it will get to 3/4 and stay that hot. Mine is starting to shit me now. All my mats that own VR's gauges dont go past half way.

[VR 252]

This is normal. Buying a cooler thermostat, bigger radiator, cai, heat shields, manifold insulators, plenum spacer ...etc will help.

The reason why it runs cooler with the air con on is when you turn the aircon on the thermo fans are always on, whereas normally it waits till it gets to passed 1/2 then fan kicks in. The dampner for the engine heat shown on the gauge in the VS's are very sensitive (I'm sure there's a better way of saying that) then the other ecotecs. The vt - vy may cool faster because they have 2 thermo fans. Still this behaviour is normal. On a vt - vy the guage wont move as much but im sure its running the same temp as the vs so no need to worry

All the vs's i have seen run at that first big mark that seems normal.
But not my vr it dose the same as all your cars are doing it shits me. My question is what temp thermostat should i go and buy stock or lower and if lower how much lower.

[VR 252]

all the vr's and vs's i have been in not one of them had this trouble but my vr that i just brought dose. im looking at replacing the thermostat first because the motor has just been rebiult and parts i would look at are new. Should i buy a standard vr termostat or a cooler one? and if cooler how much cooler? what temp thermostat should i buy?

[Calais015]

Hi guys ..I did something silly not long ago and didnt check my water...got my Vr calais home just before the temp gauge went to H and the alarm beeped as i turned her off ...I refilled it with coolant the next day (..as i belive there was only water in it before) and now it runs at 1/4 and heats up to half then drops back to 1/4 when the thermo fan kicks in. I did a 400k trip 3 days ago in high 30 degree temps and she was fine sat on 1/4 all the way to my destination...but on the way back with 100 kms to go as soon as i went up a hill the temp gauge would climb to Hot..and then on the flat resume to 1/4 ...it was a 42 degree day i'm not sure if it was anything to do with the actual radiator or tranny and it was struggling a liitle ...being sluggish..as it is not running a tranny cooler...I would appreciate any insight into this dilemma ..Thanks
I forgot to mention the aircon was on all the way down and back...