HELP VS Comodore Overheating Problems

[VS_commodore09]

Just need some advice about my VS Commodore it use to overheat bad so i replaced the radiator which i think helped the issue the temp guage use to sit on half way all the time now it sits very low most of the time but in traffic it comes up to half way slowly wich is not really a big deal but i feel that the engine is gettin hotter than the temp gauge says are there some things i can check or do to to find out if everything is workin properly

any advice at all will be appreciated

[Harvs82]

Just need some advice about my VS Commodore it use to overheat bad so i replaced the radiator which i think helped the issue the temp guage use to sit on half way all the time now it sits very low most of the time but in traffic it comes up to half way slowly wich is not really a big deal but i feel that the engine is gettin hotter than the temp gauge says are there some things i can check or do to to find out if everything is workin properly

any advice at all will be appreciated

Perfectly normal.

You should hear the cooling fan come on around 1/2 or 2/3 up the gauge, and that will drop the temperature back down. Most of the time it should sit around 1/3, or if its a really hot day then closer to 1/2 way.

[VS_commodore09]

Cheers thnx for the help

[Harvs82]

Cheers thnx for the help

No problems mate, its what we are all here for!

If you are still concerned at the cooling system, check the condition of the coolant, it should be a nice bright green colour, and not look watered down at all. Check both in the radiator and the coolant overflow tank too. If it is looking a bit brown or muddy then it definately needs changing. The commodore V6 requires a special coolant, its a lot stronger than the premixed stuff, you can get the genuine stuff at Holden, which is what I've always used, or you can get other makes elsewhere that are suited to the commodore V6.

[thorny]

The commodore V6 requires a special coolant, its a lot stronger than the premixed stuff, you can get the genuine stuff at Holden, which is what I've always used, or you can get other makes elsewhere that are suited to the commodore V6.

ever since my mechanic did a fluid change (and some other stuff - can't remember what exactly) the engine runs a lot hotter than what it used to. it used to sit just below a quarter ALL the time. could he have used the wrong coolant? i have to leave the aircon on (so the high speed fan runs) in order to keep the car from overheating. when i tow a boat and hit a hill, i just have to hope the hill isn't too big (mt ousley caused my car to have smoke billowing out the interior vents!) otherwise it gets real hot (quite often gives me an overheating alarm).

what is this 'special coolant' you speak of anyway? surely i can get it from supercheap or repco? i don't really want to go to a dealer, their prices are usually over the top

[Cheap6]

ever since my mechanic did a fluid change (and some other stuff - can't remember what exactly) the engine runs a lot hotter than what it used to. it used to sit just below a quarter ALL the time. could he have used the wrong coolant? i have to leave the aircon on (so the high speed fan runs) in order to keep the car from overheating. when i tow a boat and hit a hill, i just have to hope the hill isn't too big (mt ousley caused my car to have smoke billowing out the interior vents!) otherwise it gets real hot (quite often gives me an overheating alarm).

Sounds like it wasn't bled correctly. There are plenty of posts on here already about how to do that if youcan't take it back to him (her?).

what is this 'special coolant' you speak of anyway?

Read the bottle to find one that says it is suitable for commodore V6.

surely i can get it from supercheap or repco?

Yes, you can.

i don't really want to go to a dealer, their prices are usually over the top

Not always.

[Harvs82]

Sounds like it wasn't bled correctly. There are plenty of posts on here already about how to do that if youcan't take it back to him (her?).



Read the bottle to find one that says it is suitable for commodore V6.



Yes, you can.



Not always.

Yep, that pretty much sums it up. Its about $45 for the 5 litre coolant from Holden, plus another $13 or so for the 1 litre, which you also need, as the cooling system is basically 12 litres including the overflow bottle. What I used to do was completely flush the system and remove the thermostat, flush the block etc, and then you are left with about 3 litres of clean water in the engine, hook up the bottom radiator hose, and then tip the entire contents of the 5 litre concentrate into the radiator, and then put most of the 1 litre into the overflow bottle and then top both of them up with water. I found that was the best way to get as close to the 50/50 mix as possible. Doing it any other way you always end up with spare coolant etc.

I never had a problem using the Holden stuff, as I've mentioned in other threads the only part I replaced after 12 years and 200,000km was the water pump, due to a faulty bearing. No heater core, radiator etc replacements at all. Thats a good enough reason to use the proper stuff.

[bfc]

check the radiator sender unit....if its black swap it for a white one......turns fan on at lower temps...i had overheating problem took it to my bro (service manager at holden dealer) swapped them over...no probs since

[hellothere]

Ive been havin the same problem with mine. First started after a long drive (1.5 hrs) took it to mechanic and he sed the radiator needs changing and a few other bits and pieces. Ever since it dusent feel like its got the same power as it used to and i get a strange hint of a burning smell and when idling eg. at lights occassionally idles lumpy for a sec or 2 then goes bak to normal also temp gauge quickly rises when stationary and then begins to slowly drop when the car is in motion again. What could this be?

[BlackVXGTS]

Make sure the mechanic has used the correct coolant - 50% water and 50% ethylene glycol - not just water and an inhibiter. The genuine Holden coolant is best as Harvs82 has mentioned in his post above. Also you need to ensure that he has bled all the air from the cooling system.

[mrhotdog]

my overflow never stays full for more than 1-2 days at a time, however radiator stays full, any suggestions

[andywylie]

hey everyone, im new and i couldn't figure out how to make a new post but this thread is similar to my problem.
i have a 97 3.8 v6 VS ute
recently i got the (auto) transmission serviced and since i got i back ive have had a "higher temperature" problem.
thermostat and temperature sensor/sender have bother been replaced with genuine holden parts.
no leaks in the cooling system (besides a very slow inlet manifold gasket leak which i am soon to fix.
i believe i have a 2 stage thermofan and the low stage does not kick in.
my car usually sits between the first and second incriment on the temperature scale but has been running hotter, getting to about 85% before the high stage fan kicks in and then stops once the temperature drops to about 60%
-have taken the thermostat out and run the car with the air con on to keep it cool
-anybody shed some light on the fan problem?

[Harvs82]

hey everyone, im new and i couldn't figure out how to make a new post but this thread is similar to my problem.
i have a 97 3.8 v6 VS ute
recently i got the (auto) transmission serviced and since i got i back ive have had a "higher temperature" problem.
thermostat and temperature sensor/sender have bother been replaced with genuine holden parts.
no leaks in the cooling system (besides a very slow inlet manifold gasket leak which i am soon to fix.
i believe i have a 2 stage thermofan and the low stage does not kick in.
my car usually sits between the first and second incriment on the temperature scale but has been running hotter, getting to about 85% before the high stage fan kicks in and then stops once the temperature drops to about 60%
-have taken the thermostat out and run the car with the air con on to keep it cool
-anybody shed some light on the fan problem?

Check your low fan relay, and fuses. Taking the thermostat out will only make it run hotter, as the coolant can circulate too quickly as the radiator doesn't have enough time to cool it down again. Much better off with it in. I'd also be checking for an air lock in the cooling system, and also make sure that you are running the correct grade coolant concentrate and water, not the premixed stuff.

[andywylie]

will take your advice on the thermostat although testing has proven it runs cooler without.
using correct coolant
where abouts are the fuses for the fan?

[andywylie]

Check your low fan relay, and fuses. Taking the thermostat out will only make it run hotter, as the coolant can circulate too quickly as the radiator doesn't have enough time to cool it down again. Much better off with it in. I'd also be checking for an air lock in the cooling system, and also make sure that you are running the correct grade coolant concentrate and water, not the premixed stuff.

will take your advice on the thermostat although testing has proven it runs cooler without.
using correct coolant
where abouts are the fuses for the fan?
(new to this forum tonight and still learning how to use it properly)

[Harvs82]

will take your advice on the thermostat although testing has proven it runs cooler without.
using correct coolant
where abouts are the fuses for the fan?
(new to this forum tonight and still learning how to use it properly)

Thats assuming that the gauge is indeed reading correctly... The commodore gauges do tend to move around quite a bit, where a reading around 2/3 up the gauge is still normal... thats usually when the cooling fan kicks in on the lower speed.

Regarding the relays... they are located on the right hand side in the engine bay, they are under a black box sitting above and back from the battery. There are two relays for the fan, one is listed under LO FAN for the lower speed, and ENG FAN is the one for the high speed. You can swap over the relays with a known working one for testing purposes, but make sure its something like HORN. The other thing I forgot to mention was to check your radiator cap... if its old and crappy looking, replace it.

[andywylie]

Thats assuming that the gauge is indeed reading correctly... The commodore gauges do tend to move around quite a bit, where a reading around 2/3 up the gauge is still normal... thats usually when the cooling fan kicks in on the lower speed.

Regarding the relays... they are located on the right hand side in the engine bay, they are under a black box sitting above and back from the battery. There are two relays for the fan, one is listed under LO FAN for the lower speed, and ENG FAN is the one for the high speed. You can swap over the relays with a known working one for testing purposes, but make sure its something like HORN. The other thing I forgot to mention was to check your radiator cap... if its old and crappy looking, replace it.

one other suspicion i had was anything to do with the computer. or a module of it.
do you know of anything in the computer that tells the fan when to turn on/off
this problem only arose after i got the car back from a transmission service...more than likely coincidence because their isn't anything to do with the cooling system that the transmission people should have fiddled with.
***something which you and many people have said which ive found interesting is saying the temperature runs at around 2/3...ive owned my ute for 5 years now, and its always ran between the first and second (10 increments in total) increment(10-20%)
if the car is getting pushed harder it is known to sit maybe between the 2nd and 3rd increment which is 25% roughly on the temp scale.

[Harvs82]

one other suspicion i had was anything to do with the computer. or a module of it.
do you know of anything in the computer that tells the fan when to turn on/off
this problem only arose after i got the car back from a transmission service...more than likely coincidence because their isn't anything to do with the cooling system that the transmission people should have fiddled with.
***something which you and many people have said which ive found interesting is saying the temperature runs at around 2/3...ive owned my ute for 5 years now, and its always ran between the first and second (10 increments in total) increment(10-20%)
if the car is getting pushed harder it is known to sit maybe between the 2nd and 3rd increment which is 25% roughly on the temp scale.

The temp shouldn't 'run' at 2/3, but if you are stationary, ie at the lights or in peak traffic, seeing that level for a little while is perfectly normal, as the fan kicks in and then brings it down to just below half. When I had my VS, it used to sit on about 1/3 for normal running, and a bit below half if it was really hot outside.

Regarding the controlling of the fan, the ECU uses information from the coolant temperature SENSOR. It could be possible that you have a faulty one in your engine now, even though you have replaced it previously. From memory though, the HIGH SPEED fan is controlled soley by the ECU.

Statistics as follows:

Thermostat
Opening temp 89 to 93 Deg C
Fully open temp 106 Deg C

Fan cut in Temp:
Low speed :- above 104 Deg C
High speed :- above 109 Deg C

Fan cut out Temp:
Low speed :- below 99.5 Deg C
High speed :- below 105 Deg C

Radiator Cap pressure is 135kPa

[andywylie]

The temp shouldn't 'run' at 2/3, but if you are stationary, ie at the lights or in peak traffic, seeing that level for a little while is perfectly normal, as the fan kicks in and then brings it down to just below half. When I had my VS, it used to sit on about 1/3 for normal running, and a bit below half if it was really hot outside.

Regarding the controlling of the fan, the ECU uses information from the coolant temperature SENSOR. It could be possible that you have a faulty one in your engine now, even though you have replaced it previously. From memory though, the HIGH SPEED fan is controlled soley by the ECU.

Statistics as follows:

Thermostat
Opening temp 89 to 93 Deg C
Fully open temp 106 Deg C

Fan cut in Temp:
Low speed :- above 104 Deg C
High speed :- above 109 Deg C

Fan cut out Temp:
Low speed :- below 99.5 Deg C
High speed :- below 105 Deg C

Radiator Cap pressure is 135kPa

thanks for that, would you happen to know also what oil pressure a 92 Vr 3800 engine runs at?

[andywylie]

The temp shouldn't 'run' at 2/3, but if you are stationary, ie at the lights or in peak traffic, seeing that level for a little while is perfectly normal, as the fan kicks in and then brings it down to just below half. When I had my VS, it used to sit on about 1/3 for normal running, and a bit below half if it was really hot outside.

Regarding the controlling of the fan, the ECU uses information from the coolant temperature SENSOR. It could be possible that you have a faulty one in your engine now, even though you have replaced it previously. From memory though, the HIGH SPEED fan is controlled soley by the ECU.

Statistics as follows:

Thermostat
Opening temp 89 to 93 Deg C
Fully open temp 106 Deg C

Fan cut in Temp:
Low speed :- above 104 Deg C
High speed :- above 109 Deg C

Fan cut out Temp:
Low speed :- below 99.5 Deg C
High speed :- below 105 Deg C

Radiator Cap pressure is 135kPa

back to my car, been onto a mechanic, hes thinking that my transmission is overheating due to a blockage, do you know if that will affect any temperature readings and /or the time that the fan cuts in.