VZ running hot every trip

[exanVZ]

Well I changed it over and screwed on as tight as I could (hand tight is ok yea?) but still running hot. I will let it cool right down before giving it a second chance, current perth temp still 34-35c.

I removed the old cap while the engine was still quite hot (but not too hot) and noticed the coolant was almost level with the bottom of the neck where the cap screws on (full!) and then I checked the overflow (coolant checker thing passenger side) which was almost double the 'max' level on the dipstick so could it be that there is now too much coolant? I added 2L recently when the problems started without really knowing what I was doing, could it mixed brands (I used tectaloy heavy duty 90+)? Is there an easy way to drain some out (if there is such a thing as too much) so that I can test it with regular levels?

Temps are still getting hot, over 120c (turned on diagnostic to test) but within a minute of turning on the hot air it drops to 112-115ish (3/4 between C & H) where it will sit as long as the hot air is on. Seems to me it is just getting a little too hot.

If it was a thermo getting stuck, temps wouldnt behave so consistently (i think...) and there are no leaks visible and not a drop has hit my carport since I bought this car (7 months+) so I am pretty sure that it can't be a leak either. Again oil is okay too (that I do know how to check).

Any suggestions before forking out to get this looked at? Seriously can't afford that right now. Really appreciate the advice everyone, keep it coming!

As a last alternative, anyone who knows what they're doing wanna take a look for a carton or mates rates or something?

Cheers,

Patrick

 

[Luke52]

The only coolant I'd use in an Alloytec is the Nulon long-life red coolant. Matches the GM 6277M specifications.

It's not good to mix colours, either. The coolant you used to top it up would have been green, right? Do you know what colour the coolant already in the system was?

After I had some heating/cooling issues, I got the cooling system flushed and had the coolant replaced. That was just for my peace of mind, really. Plus the "coolant" in the engine looked clear, so I'm pretty sure it only had water in it since I bought it...

But now I know exactly what's in it, and that it's good coolant matching the right specifications.

I'd definitely get it looked at ASAP mate. I know I'd rather replace a thermostat than a pair of head gaskets.

 

[exanVZ]

Thanks Luke if I change it i'll go the red coolant for alloytechs.

I did the 2 hole mod today as I had some time. Engine runs a bit more rough at the idle but goes a lot smoother on take off. I assume needs to get used to being able to breathe now.

I also bled some air out of the cooling system using the coke bottle method, all the coolant both under the rad cap and out of the bleed valve was green, so I assume what was in there before was green. I doubt 2L of green could make much difference in colour if it was all red. Let it get real hot then cool a bit, did it again but no air came out so should be okay there.

Felt the temps on the hoses as I heard thats also a good way to tell if everythings working okay, top hose quite hot to touch, bottom hose warm but not too hot to touch.

Rang a local mechanic today who suggested taking it to natrad for a radiator clean, rang natrad who suggested taking it to a mechanic to get the thermostat checked.
Haven't booked it in anywhere yet.

Kind of at a loss as to what to do as I can't really see any faults, other than running hot.

Cheers,

Patrick

 

[imoore]

if the cooling system has a mixture of green and red it can cause an engine to over heat. if left long enough it will turn to a jelly blocking radiator and water jacket. if like you say it has been mixed id recommend you take it to a engine cooling specialist and get them to flush it out asap

Ian

 

[exanVZ]

Thanks Ian, I'm going to take it to Natrad this week coming as soon as I get the chance. I am not sure if it has mixed or not, but I think its out of my league to fix so going to get the experts to take a look. Will come back and let you all know how I go in case anyone else has a simillar issue.

Cheers,

Patrick

 

[Luke52]

As I said before, if you're replacing the coolant, use the Nulon long-life red stuff at 50/50.

 

[bigdaddycool]

I've had this issue a few times on my car..........

1. Check engine oil on flat surface, be sure to check the stick two or three times.
A. When the car is cold, take the coolant cap off (make sure u see coolant).
B. Bleed the coolant (a must on these cars!)

* To bleed the coolant. When the car is cold, take off the coolant cap, start the car and let it run for 10 minutes with the cap off (you will notice air-bubbles coming out). Top up the coolant, repeat (but only do this when the car is cold, as the car gets hotter the coolant will being to rise, get hotter, flow.....) If you let it get too hot you could damage the engine or your water pump.

It's a safe thing to do, just takes practice. Do it once, top it up, repeat once or twice within the next week and she should be right.

 

[exanVZ]

Thanks guys, I had it looked at by Natrad this morning and within about 15 minutes they confirmed that the fault is thermostat. Any ideas how much I am going to be looking at to get it replaced? Not a job im confortable doing myself. I'd just like a ballpark figure so I don't get ripped off.

Cheers,

Patrick

 

[exanVZ]

well getting the thermostat replaced today. will see how it goes after that.
have also asked the mechanic to give me a heads up on any preventative maintenance it might be worthwhile to perform while he has things in pieces (eg. plugs)

thanks for the advice recieved here so far

 

[exanVZ]

Thermostat changed yesterday, and car has been running well since. Hasn't risen above 1/4 on the temp gauge.

The mechanic who did it hasn't done a VZ before mine, and said they are a real pain in the ass, but also mentioned that the alloytech engine was made for the front wheel drive cars in the US which usually results in the engine being positioned differently, and the thermostat not being so difficult to reach. Probably one of the stupidest decisions holden could have made for this car.

Glad it is sorted now anyway.

Patrick