VZ 3.6ltr cooling system woes

[MechanicsSon]

Good day gentleman... and ladies,

I bought myself a 2005 Holden VZ 3.6ltr wagon just over a year ago and ever since i've owned it, i have nothing but trouble...
Please believe me, i have read over and over previous posts and whilst some have helped, none have resolved or even quiet described my issue.
I am posting here because i do not know what is wrong with my car if anything!?

firstly, it has never overheated in my possession, but there have been many signs of coolant issues to keep me on my toes.

Originally i found the fabled broken radiator cap, which i replaced with an aftermarket one from a reputable distributor.
following on from this, i found the water pump bearings to have failed. I replaced this also with an aftermarket part, this time from ebay ( I know everyone recommends Holden genuine).
things seemed good for a little while but then, i found the radiator to be leaking from the drivers side plastic tank, where it joins (no cracks) so again, i jumped on ebay found a cheap part and replaced it.
I figured all was dandy until!
The radiator went again, same place, same issue within the year. I also found the heater tap to be leaking and signs of leaks around the thermostat...
I have since replaced the thermostat, brand new genuine GM with all three o-rings and new gasket, new inlet pipe o-ring and rubber seal, all of the hoses and new screw type fasteners and this time, i went with a much more expensive all aluminium radiator.
I have also replaced the temperature sender (this is genuine GM) and bought a genuine radiator cap.

So what is my issue?

I'm too scared to drive the thing. The temperature gets to just over a quarter and that's it... the fans never come on, the rubber pipes are rock hard and i'm worried something is a miss!

I tested the fan relays and wires by unplugging the wire to the temperature sender (thank you poster) and the fans came on like they should, the pipes became malleable and the temp dropped back to a quarter. I bought the new sender in case the old one wasn't reading properly but the new one does exactly the same. I cant help but feel there is too much pressure in the system causing the plastic tank radiators to 'pop' let alone every other leak, yet you would think if the pressure got too high it would 'vent' out the over flow to the reservoir. There are no other signs of head gasket issues but no, i have not had it pressure tested yet.

I believe i have been refilling the radiator properly, utilizing the radiator air release plug as well as setting the heater on full and running it up to temp to purge any remaining air etc. but instead of waiting for the thermo's to kick in, i have shut her down after it becomes obvious the thermostat has opened.

so any ideas?

Also, if i may;
Does anyone know the proper torque setting for the temperature sender? couldn't find that anywhere.
I know the coolant level should be checked in the reservoir but, when you remove the cap (cold) you should also be able to see a level in the inlet pipe? I had this at one stage but i've had so many leaks, i started to wonder if i was simply overfilling it?

p.s. i just read that you can check the operating temperature, so that a nice thing to know i'll have to try it out.

Thanks for your time,
Regards
MechanicsSon

 

[greenacc]

So the hoses are harder than on other cars at operating temp?
To give you some hope my VE V6 has only needed a thermostat, orings, a top hose and a new cap in last 6 years.
Can you push the spring in your cap down with your fingers if you remove it ?

 

[AdventraAddict]

The Alloytec runs hotter by design than previous engines.. Fan speed 1 comes in at 108 degrees and Fan 2 at 113... The gauge runs at or a few mm above quarter...
Sounds like your car is fine to me but you just had a run of replacing wear parts in the system... Mine has gone through a few expansion caps, the return valve gets blocked... To ease your mind buy a $10 OBD2 Bluetooth dongle and put torque on your phone then you can learn the temperature and behaviour while driving..
(flowing traffic mine is 90-93 in traffic climbs to 108 then fans bring it back to 102.. if that helps... Oh and hoses are pretty firm when pressured up yes)

 

[MechanicsSon]

Good day guys,
I tried to compare how 'firm' the hoses felt, against my 3.5ltr Nissan at operating temp. The nissan was no where near as hard but the fans were running and the Holdens hoses were not hard once the fans were manipulated into running... The cap is firm but can be depressed with your fingers.
I admit it seems like all is well but after having it idle in the drive way for approximately and hour, you would think the temperature would be sufficient to start the fans.
Thanks AdventraAddict for your advice on the OBD2 dongle, i had no idea these were available. I had seriously been considering buying a $400-$500 unit. I ordered the dongle today, so i look forward to seeing how well it works. Sounds like a must have for all DIY'ers.
Ill be sure to let you know how it goes.

 

[greenacc]

Surely after an hour the fans should be coming on. Perhaps your temp sender or fan solenoids are faulty.
Do the Nissan and Holden systems run as the same pressure as stated on the caps??
At least you know your cooling system is holding pressure so all your issues with leaks are sorted!!

 

[timmy201]

One problem with a lot of stuff like this these days is they are made out of plastic. Radiator caps, radiator tanks, screws, pipes etc, and they all get old and break (or are dodgy quality). Have you had anyone (e.g. cooling system specialist) look into it to see if there is a problem?

Luckily the dealer I bought mine from gave me a 3 year warranty so they replaced: radiator cap, water pump & radiator. Once all that was replaced it's been fine. It stays exactly on the quarter temp on the gauge.

The cooling system should be under pressure. The higher the pressure, the higher the boiling point of the coolant.

What exactly is the issue that is worrying you? The pressure in the hoses? The fans kicking in?

 

[DeanoV6]

The Alloytec runs hotter by design than previous engines.. Fan speed 1 comes in at 108 degrees and Fan 2 at 113... The gauge runs at or a few mm above quarter...
Sounds like your car is fine to me but you just had a run of replacing wear parts in the system... Mine has gone through a few expansion caps, the return valve gets blocked... To ease your mind buy a $10 OBD2 Bluetooth dongle and put torque on your phone then you can learn the temperature and behaviour while driving..
(flowing traffic mine is 90-93 in traffic climbs to 108 then fans bring it back to 102.. if that helps... Oh and hoses are pretty firm when pressured up yes)

+1


MechanicsSon Your experiences don't sound too different to mine, once you have done everything they go good.

 

[Benboy]

Suggest you consult a Radiator/Engine Cooling Specialist. They can flush your cooling system as well as pressure test it and the filler cap. Might save you more unnecessary expense ! Good luck.

 

[AdventraAddict]

Put your dash into diagnostic mode by holding mode and set as you turn on the key, then press mode about 14 times through all the readings you will get ECU digital coolant temp... then you can watch what is really happening... (The temp needle isn't actually a linear analog display.. fairly useless) if the fans dont kick in by 110 you have relay or fuse issue most likely...
I actually left my fan pack unplugged by accident when I installed my trans cooler... Did 1500kms without an overheat LOL till I found it..

 

[greenacc]

To Adventraaddict, I left my fan unplugged on my first track day... Had been changing balancers the night before so had the shroud off. It became obvious after about 5 laps had to pull into pits and plug it in...
Off topic sorry.