Technical Thermostats and Radiator fans

[Bushboy]

Hello.

First post in here in a looooooong while. Just purchased an MK1 16v Sporting so no doubt will be posting in here a fair bit more..

The Sporting needs a new thermostat. Heater fan is blowing cold and the temp gauge is all over the place. Can anyone confirm if the 1.2 8v thermostat and the 16v thermostat are the same (saves me buying one if they are..)?

Also, with the temp gauge being a bit manic due to the termostat, would this cause the radiator fan switch to play up too? My problem is that the rad fan didnt kick in at all even though the temp gauge displayed a couple of silly temps (although mostly hovered around 90). I have tested the fan itself and it spins up fine. Could the faulty thermostat be causing the switch to misread temps (or that no coolant is getting to it..) or is it just likely that the switch is knackered anyway?

Grabbing a new thermostat anyway on the way home from work tomorrow (do have a 1.2 8v anyway if anyone can confirm fitment?), does anyone know if Halfords stock the 16v thermostat? I know I can get it cheaper elsewhere but Halfords really is the only sort of place open after 6 on a Saturday.

Cheers Punto people :slayer:

 

[blu73]

Ah now then stranger, long time indeed. Welcome home! :wave:

Yes, thermostat is same, see here. You still have one of them lying about after all this time?

Can't comment on the fan, its fed by magic electric so i don't understand it lol

 

[Dcthebear]

Needs confirming by another forum member but I think the fan is controlled by a water temperature sensor. The thermostat is not electrically controlled but works by expanding under heat to open the valve.

 

[tinytim]

Suggest thorough bleeding of cooling system and a good clean of the temperature gauge sensor; reasonable to change the thermostat but if the spare you have is used its worth testing it first........
keep us posted

 

[Bushboy]

I've ordered both the Thermostat and the fan switch sensor anyway. The termostat I have isn't new so thought I may as well get a new one.

Makes sense to replace both instead of just doing the thermostat and then finding I need to redrain the coolant to replace the switch anyway.

Can anyone confirm where the bleed points are on the MK1 punto cooling system? Also is there any specific proceedure to doing it? Done it on a few cars before but some have 2 or more bleed points etc and need to be done in order. :bang:

Cheers

 

[blu73]

Not sure, as i only have the GT (which bizarrely doesn't have any bleed screws at all).

If there is 2 on a car then one tends to be for the engine radiator, and the other is for the heater matrix usually. Just have a good gander in the bay for some bleed screws, sure they can't be too hard to spot.

So do we get to see any pictures of this car then??

 

[Bushboy]

Found a handy guide by Dave which goes through the bleed proceedure. Pretty much as I thought really

You have Alex's old GT don't you? Nearly bought it myself when he was trying to shift it!

Some pics here, just took them last night on the way back from collecting it.

 

[blu73]

Looks great! but really needs some clear side repeaters..
And yes, I got Alex's old GT3.. Someone had to buy it before a chav did hehe - i just putting it back to totally stock and keeping it serviced.

 

[Bushboy]

Clear repeaters are on the list once I get this issue sorted.

But otherwise I'm just looking to keep it standard. It's totally stock at the moment and really tidy apart from a few bits here and there, such as the vinyl on the b pillars being a bit flakey. Just needs a bit of a tidy up here and there but is totally solid and the paint is in fantastic condition.

May look into dropping in the 1.4 16v lump in the future though. Makes more sence than tuning the 1.2.

 

[blu73]

Good stuff.. Reckon refurb the wheels in anthracite would look epic on yellow

 

[Bushboy]

Great success ...

Well, sort of.

Thought I would have a go at bleeding the cooling system. Turned out there was around a litre of air in the system. Started the car and left it on the drive for 10 mins to warm up. Then got bored of waiting and decided to go for a drive to speed up the process... It wouldn't warm up. No matter how I drove, the needle would only sit at a quarter.

Got back and left it on the drive a bit longer and thankfully it started to warm up properly. Got to 90 degrees and the fan kicked in :slayer: Stayed at a steady 90 for another 10 mins with the fan kicking in and out

So. I've ordered coolant, thermostat and a fan switch. No need for the fan switch as it's working fine. The thermostat seems like it is stuck open (hence not warming up properly) so that needs replacing and it seems the majority of the cooling system is full of water anyway so the coolant will come in handy

Just waiting for it to cool down now and I'll check if it needs topping up... Here's a pic...

 

[blu73]

Mmm, airbox looks exactly same as a PuntoGT one... In which case i have a spare pipercross panel filter (somewhere), PM me if you want it

 

[Bushboy]

Hmm.. Have you got the complete airbox spare? Could do with the hosing from the throttle body to the box thing that sits on the engine and then the bit that goes to the filter box at the front. Mines got duct tape around it at one point. Presume its split underneath.

Oh also, noticed the Punto has aircon :slayer:... The whole system is there, just no button inside the car :bang:.. Presume the panel was replaced at some point for a non aircon one. Shame really. Guessing the aircon switch would just be a standard on/off switch though so if I can find the wiring, I may be able to hook up my own

 

[blu73]

no, its just the panel filter itself but...

http://www.ebay.co.uk/itm/Fiat-Punt...Model:Punto&hash=item4165b8427c#ht_500wt_1413

or

http://www.ebay.co.uk/itm/Fiat-Punt...CarParts_SM&hash=item3cc6309a77#ht_500wt_1180



I have worked out they are slightly different from looking at the pics, but i think the filter would fit fine..

 

[Bushboy]

Thermostat, fan switch and coolant came today and with the lovely weather, it seemed rude not to have a fiddle.

Dumped the cooling system (which was totally water) and removed the old stat. Perfect condition. Looked quite new infact and defo not stuck open as it was closed :bang:... Replaced with the new one anyway.

I decided to leave the switch as the old one is fine anyway. I've popped it into my tool box for future use if needed.

Refilled the cooling system with the new coolant (50:50 mix) and bled.

Took the car out for a shake down and still, it wont get over the quarter mark on the temp gauge when driving. Parked up and left it running and as expected, the gauge rose slowly. Got to the mid point where the fan kicked in and it hovered around the mid point for the next 10 mins. Decided I was happy with that so drove off. pretty much straight away, the needle starts to drop and after a bit more driving, settles around the quarter mark:bang:...

Im not that unhappy about this. Afterall, its not overheating :slayer:... Just concerned it isn't fully getting up to temp.

Anyone any ideas? Im lost...

 

[blu73]

Mmmm, weird one for sure. Are we sure the fan is kicking in when the gauge reads the correct temp.. Not sure personally what temp the fan does kick in on these myself.

I'm just thinking perhaps the temp sensor for the gauge isn't sending the right signal - possibly due to corrosion build up if it didn't have coolant in with the water. Whip it out and test it on a multimeter.. As if this is the case everything is prob working as it should which it sounds like it is tbh, and its the gauge is wrong..

Just an idea.

 

[Bushboy]

I did think that but not convinced as the fan switch is rated to come on at around 90 degrees, which is the mid point on the dial.. The fan and switch seem to be working perfectly well to me and the gauge does seem to be right as far as at which point it comes on.

As I say though, I'm not overly concerned as at least its not overheading.

 

[fingers99]

Pretty normal behaviour t my mind. After all, when moving at any speed the rad gets a lot of air.

 

[blu73]

i was beginning to think the same.. just not sure whats normal running temps for that engine so can't really comment but it does sound like its working as it should..

 

[Bushboy]

Hmm. You may be right.. Although I have nothing to compare it to really. The majority of my Fire engined cars had heating system issues

Just comparing it to pretty much every single non Fiat car that I've owned which gets to running temp and stays there thanks to the thermostat and fan keeping everything in check.