The noobie and the thermostat

[criten]

I'm a bit of a noob but trying to learn

I noticed the heater in the car takes a real long time to come on, and after cleaning the heater core etc. it still didn't improve. I should also note that if the car idles for 5 - 15 min (depending on if its a hot day or not) the engine will overheat. So I next thought of the thermostat...

The previous owner of the car tells me the thermostat is broken, its always open, and that its not worth fixing. Also says that with a working thermostat, the car overheats so there is some kind of cooling issue to address. I'm thinking the radiator, but I'm told a new one was installed about 5 years ago - but I'm certain this isn't true because its been damaged - looks much like I'd expect from when he jacked up the car from the bar just below the radiator (a big no no) about 10 years ago. Radiator has a crimp in the bottom, about 5cm deep that presses a bunch of the fins together. It also has many fins pressed together from where stones have hit it, and seems to be a matter of spotting an area that isn't damaged. It doesn't leak at all, but my previous experience in computers tells me that fin seperation with heat displacement devices is fairly important. Old owner also says that the thermostat hasn't worked for a fair while and by installing a new one I could possibly cause more problems by adding more heat and pressure, such as at the welch plugs and vacuum seal - or that the cooling issue itself may be an underlying issue with these.

Obviously from story about him screwing the radiator from jacking the car in the wrong spot, he isn't exactly a bright bloke. Is it worth trying to fix the thermostat? Is it true what the old owner said about damage by pressurization?

I should probably just try a new thermostat and radiator, if that doesn't work I can always revert back to old thermostat and work on where else it could be

I should probably get/build myself an ALDL cable to check my sensors are working - no errors when I do the short pin & dash display thingo

[azkwazere]

Change the thermostat.

Its broken, if it leads to more things breaking, so be it.... It needs to be fixed and your cooling system will appreciate it.

Usually thermos dont block fully open, its fully closed... but, replace it anyway.

Cost you like $15-$30 depending on where you go, new coolant + gasket + goo.

Everything needs to be functioning correctly.

aZk.

[PaRaDoX]

replace the thermostat and see what it does then, still overheads then your radiator isnt working efficiently, my bet is it'd be jammed shut not open...

its a series 1? they are notorious for leaking coolant from the bazillion hoses they have... make sure your cooling systems topped up

[savage1987]

My s1 thermostat was stuck open when I bought the car. Unusual, yes, but possible. I replaced my own, easy job just takes a while because Holden put it somewhere stupid in the s1.

Radiators don't usually get hit by rocks, air con condenser thingys are in front of them. Does your VN not have air con?

Paradox, you are so right about VN s1 hoses leaking coolant constantly. I don't know where mine is leaking from, there's a coolant, power steering, trans fluid and motor oil leak so if I don't look after the car, pretty much everything will run out lol!! All minor, coolant leak is biggest and I have no idea where it's from! Waiting for a bit of spare cash and that motor will be getting a lot of attention.

[criten]

Done a lil bit of research about it

Was a professional who jimmied the thermostat so its stuck open... apparently 10 years ago it was having major cooling problems, and thats how it was solved.

Had cardboard under the car, doesn't seem to leak anything when its parked

I can get the car to cook already in peak hour traffic or idling it for 15 min (guage just continues to rise and rise)... I'm certain there is a problem with the cooling system now.

Was suggested to me that I flush the coolant to check the flow... refill (slowly) and then bleed any air out. Failing that, begin pulling apart some of these hoses and checking for blocks. This seems logical to me, but still, input needed cause I'm a noob

I have a series 1, air con is fitted but is out of action and I have the short drive belt too so it has nothing to run from. There are a few things in front of the radiator, but it still seems kinda open - bumper is quite damaged (its actually in two peices but mounts hold it together), I might be missing something?

What concerns me most about the radiator is it seems all the fins are adjoining - so its as good as one solid peice of metal for cooling. Surely this can't be good. Only looks like rather small stones have hit it, dents at most are 1cm diameter but there are lots and lots. I could probably repair most of these with plyers and a good hour

[savage1987]

Are you sure you're looking at the radiator fins? If it's what you can see from the front of the car it's the air con system cooler, not the radiator. Found this out when I changed my radiator, only to realise it still looked like sh!t from the front..

However even if it is the thing in front of the radiator that's stuffed, this would probably be blocking a good lot of air flow to the radiator itself, so probably a good thing to replace first!!

Sam

[criten]

Positive its the radiator... identified from the manual. In the front of the car its just the bumper, radiator, and fan, so if theres supposed to be air conn crap there its not.

As I say, air conn isn't even connected to drive belt so not much chance it'll work. Also needs to be recharged. I cbf, I can roll down a window.

[savage1987]

OK the air con thingy I'm talking about is the size of the actual radiator...covers the whole thing, easily mistaken for (as I mistook it for) the radiator itself. It's not like a little thing off to one side or anything, at least in my s1 V6 it's not.


On another note, you should think about tearing out the whole air con system (if you're not going to use it) as there's a fair bit of weight to be saved there and it probably won't work too well after not being used for so long anyway

[criten]

Identified a problem with the water pump today. Its leaking coolant from one of the seals. Few minor leaks with hoses that probably could use replacement on the coolant line. I am getting flow with the coolant tho. I don't need to top up the coolant often so the leaks can't be that bad

Also found out today the welch plugs were done about 2 - 3 years ago, so less chance I'll have any trouble with those

Identified a rather minor oil leak too on the engine block - only need to top it up every few months so its not all that bad currently, but I will have to look at getting a new gasket for that seal sometime soon. Coolant seems clear of oil so not really a related problem

[Dezza]

also make sure your thermo fan is comming on im having the same problems atm with it overheating in traffic and just sitting but my thermo isnt working so worth a look aswell

[MyVPIsFasterThanYourVP]

if the thermostat is stuck closed the car will overheat just idling in the drive, if the thermostat is taken out the car will overheat eventually because there is no restriction to the coolant flow, and the radiator cant transfer enough air unless your thermostat is correctly functioning. Also the computer makes the engine run rich if it thinks its cold.

[savage1987]

That is bollocks. The thermostat sticks open, water is constantly flowing, as long as you have a working fan the car will barely even make it up to temp. Trust me, I had a permanently open thermostat in my VN for a good couple of months, before that it was my dad's and was like that for YEARS.

It will run rich though you're spot on there. Proper temperature: instant gain in fuel economy.

Sam