{GUIDE} vz overheating problems

[Benboy]

Great advice. One of the 'tricks' used in the past (in addition to the obvious requirement to bleed) was to raise the fron of the vehicle (rtamps etc) which also helps to distribute the coolant into the 'harder to get too' locations. This was prior to the inclusion of bleed valves/screws/etc

 

[mike2176]

Tried this when engine was relatively cool to start. With the radiator cap off as soon as I started the engine it just spat loads of coolant out of the radiator fill point, no chance of putting anything back in!

Was it too hot to start with?

 

[SVTato]

Sticky this sh*t or add to FAQ and add some pics would be great.


Sent from my iPhone using Tapatalk

 

[mike2176]

Spoke to a mechanic earlier and apparently the VZ 5.7 V8 2006 doesn't have a bleed valve? Spent ages looking for it, then just filled up at radiator and made sure overflow level / dipstick was good, replaced rad cap and went for a drive. All seems well!

Although, as I was looking under the bonnet i realised I left a tube off from when I cleaned the throttle body. It's a small one coming off of the main air intake from the air filter box. Could this have caused it to overheat? Thinking about it, on the test drive after cleaning TB I did go for it a bit, and all seemed fine. It was the next day that it overheated, and I started trying to bleed the radiator.

Could this be the cause of it overheating?

 

[Deepo1985]

Spoke to a mechanic earlier and apparently the VZ 5.7 V8 2006 doesn't have a bleed valve? Spent ages looking for it, then just filled up at radiator and made sure overflow level / dipstick was good, replaced rad cap and went for a drive. All seems well!

Although, as I was looking under the bonnet i realised I left a tube off from when I cleaned the throttle body. It's a small one coming off of the main air intake from the air filter box. Could this have caused it to overheat? Thinking about it, on the test drive after cleaning TB I did go for it a bit, and all seemed fine. It was the next day that it overheated, and I started trying to bleed the radiator.

Could this be the cause of it overheating?

hmmm..... I don't believe the 5.7 doesn't have a bleed screw , there would have to be one somewhere,maybe have a look in a Gregory's or Haines service book if you get a chance .... Also that part you have identified that you left off wouldn't of caused it to overheat , the v6 models have a similar part on the inside of the pipe closest to the power steering bottle , it has nothing to do with the cooling system so I'm pretty sure the v8 models are the same ...

 

[dkrupljanin]

(vzdriver; Gday guys please help! You seem to know what you are talking about and I have tried everything you have said. I have a 05 vz which started making a bubbling sound so I changed the radiator cap and with in a couple of days it overheated. Not knowing about the bleeding issue i got a little upset and bought a new thermostat radiator and water pump and installed them. while I was there gave the car a full service including new oils and coolants. The car is now running fine but at high load like having to go slow up a big hill the car will overheat but will idle for hours on end and sit on a freeway at 200klm and not miss a beat, the motor is still powerfull and running great but cant figure out this problem. Tonight I was trying to bleed it again and I noticed that the coolant smells funny dosnt have that sweet coolant smell. If anyone has any pointers please let me know as I am going insane.)



Hi there vzdriver. This post only refers to VZ 3.6L Alloytec.There are only a couple of things that could be causing this problem. I have VZ myself and have had few nigthmares as well. At the front of the engine there is timing chain cover, in the center of the engine, behind the water pump, there is silicon gasket and rubber gasket used to seal the water pump from the engine oil that circulates around timing chains. There is chance that could be the place where your water is mixing with oil. That could be a cheaper version of it. The other is most likely your head gasket, where there is breach in seperation in between your oil and water jets. Just to let you know that genuine parts are the smartest option but not the cheapest one. If you do end up doing the head gasket, make sure you preassure test first to locate the faulty one. Dont forget to replace cylinder head bolts for new ones.
Wish you all the best.

 

[nitemares]

Saved the CREWMAN from cooking.

Thank You so very much for this thread.

My story:-

I have a 70km each way commute to and from work. Coming home last night I noticed that my temp gauge was moving up and down with rather large swings. When I had about 20k's to go to get home my high temp alert came on. I turned off the AirCon, turned on the heater and was able to drop the temp down enough to continue home.

I was really worried that something major had let go. After I got home I let the car cool down and opened the fill point on the side of the motor. It was filled to the top. The overflow bottle was indicating a height between the two arrows. To say I was scratching my head at this point was an understatement....thermostat was the next possibility that came to mind. For the life of me I could not find the bloody thing.

So off to this forum....love it...love it....love it.

I cannot believe that the thermostat is at the back of the motor.....bugger.

Okay, I followed the tips in this thread and the other one about changing/draining the coolant. With a combination of the two I found the bleed screw, and at 10.30 p.m. last night I was pouring three litres of coolant into my car......the number 11 litres sticks in my memory....so that means I was 25 to 30 percent down on coolant.

Sheesh how is that possible.

Coming to work this morning with nothing running....temp gauge never moved more than a needle width above quarter gauge.....with AirCon running never moved....with heater running it dropped down to around the quarter gauge mark.

The people who wrote this thread need bronzing....you have saved my bacon and kept my crewman on the road....love your work. Thank You.

:idea3:

 

[RiCeY]

I would advise fitting a new coolant cap as that is most likely the point where air is getting into the system.

 

[diysv6]

Capacity of overflow container under the left front mudguard

Hi All,
I have a 2004 SV6. To date I have not found this "capacity" stated anywhere in my car manuals. When changing the engine coolant it is recommended that the overflow container be removed, washed out and new coolant be added to the container. I have found that about 550ml is about right for the markings on the yellow dip-stick to be related to the circles/triangles etc stamped into the dipstick. I am reluctant to manually syphon out the excess fluid and don't have a small fluid pump. In one instance the overflow container was excessively full from a faulty radiator cap. I then removed the container, recovered the fluid, reinstalled it and poured in 550ml. Kept the excess, it was clean for future use. Use protective gear to protect from spills..etc. Hope this is of some help.

 

[TwoUpTourer]

Righty o folk's , lets get rid of the myth of not having to bleed the radiator.

I read this two years after you wrote it, and I want to thank you for it! Did a lot of searching and you were the only one to give a correct and concise appraisal of the problem and how to fix it.

Thanks!!!
John