Strange Cooling System Problem, K11 1.0

R

rocco1504

Hi

I'm new here and was hoping someone could give me some advice regarding a cooling problem I have.

OK, so took the car on a 30 mile round trip Thurs, as I was coming back, noticed the Temp Gauge wasn't working, so got home, opened bonnet, Top hose hot, bottom hose cold; Right me thinks, New Thermostat needed !, get one put it in, after having drilled a small ( 2mm ) hole in the stat, as it wasn't original and didn't have one, and heard that this would aid bleeding, then go on to refill the car with new coolant, with the heater controls set to hot, and then run the car for what seemed like ages, still bottom hose not getting hot, or gauge working, let cool and topped up, run again, still bottom hose not getting hot, or gauge working............then took it for a few miles run, got back, bottom hose stone cold, and still no gauge working.

Anyway, I may need a new Temp Sender, but cannot work out why the bottom hose is still cold, as I'm getting hot air from the heater, but I can't think of anything else that could be causing this, and any sparks of Micra wisdom would be very gratefully received.

Thanks for looking
 
Hi
Thank for the reply.
I can't see it being the rad, as it had an accident a few years ago, and had a new Rad put in, and has only done about 10 k, if that, on that.

Gauge not moving at all, and fan not even trying to cut in

To be honest, I wouldn't have a clue how to test any of the sensors, I would probably go down the route of replacing the Coolant sensor, behind the Dizzy, If I'm correct, but not sure which one it is, top or bottom ?.
Not even sure where I'd find the gauge sensor ?, I've never worked on Micras before, and my mechanical knowledge ends with purely mechanical cars, I.E. anything before about 1985.

But thanks again, it gives me things to look for.
 
always test & diagnose all potential causes factually before assuming its fine, like being a detective.

check for air gaps.
try draining out the coolant via bottom hose (store coolant if its good to re use), then pour water down the filler, like a garden hose, and see if it gushes out the bottom at the same rate. if it only trickles out then its blocked from prob old corrosion or debris or if radweld was used before.

two sensors behind the dizzy. single pin is the gauge. double pin is the ecu coolant sensor. find sensors in spare scrappys, autoparts, dealers, ebay
 
Hi Frank
Not tried that yet, but will try tomorrow, I'm a bit too old for Nocturnal vehicle repairs.

PollyP:- I will try the hose in the Rad tomorrow, and if I get really adventurous perhaps reverse flush the block.
As for testing the Sensors, it's just something I can't do, I don't have a multimeter, and my knowledge of vehicle electrics runs to perhaps changing a headlamp bulb, mechanics I'm OK with.

Thing is this is a really low mileage car, 50K, that I inherited from my very aged mother, but it hasn't been looked after in it's life, apart from minor services.

But I really do appreciate the input from both of you, it is very helpful.
 
Hi again guys

Just one more thing about this, When I've had the heater running whilst having this problem, I get hot air through every vent, except the two in the centre of the dash board, which blow cold.

Stupid question I know, but is there an optimum setting for the heater to be on when you refill the rad etc. ?
 
The two cold vents issue is common. Only gets hot when turned to full face.

When u drain & bleed the system, set heater to full hot to open the coolant valve n let air escape
 
Hi again PollyP

I realise the heater needs to be set to hot, I just wondered if there was a "Best" setting for it to be on ?.

I really appreciate the replies you guys have left, this seems to be a really friendly Forum, unlike some I've been involved in.

Anyway, My mate who's a fully Bosch trained top mechanic is coming this evening to have a look, hopefully it's something fairly easy, and not too expensive.

Thanks again, and I'll post a conclusion when it's sorted.
 
i find you can never fully fill it whatever you do rocco, i just brim it then take it for a run
then top it up after its cooled down :)
 
when draining & bleeding the system, set heat to full hot. doesn't matter what the divertor or fan setting is.

after it's bled, for normal use I usually cold start with the heater at full cold to shut off the coolant through the heater matrix so that the engine gets upto temp and mixture runs closed loop asap.
only once the engine's upto temp do I then consider turning up the heater dial.
 

Similar threads

CPhoenix
Cooling Issues
Replies
11
Views
2K
CPhoenix
CPhoenix
M
K12 Cooling system problem
Replies
13
Views
4K
MichaelD
M
M
No pressure in cooling system
Replies
6
Views
692
Wizzini
W
micras69
cooling and starting problems
Replies
8
Views
1K
solarice
solarice
superls
strange problem
Replies
4
Views
1K
superls
superls
Back
Top