As the title states, in normal driving conditions, does your electric fan generally run most of the time when at stand still at traffic lights in good old Sydney traffic?

Mine runs intermittently in traffic. It used to run constantly when at running temp but I fixed this by replacing the thermostat. Thermo wasn't opening fully or at the right temp

I changed the thermostat and problem is still there. The car only 7k over the past 4 yrs so should I run a flush?

Check for air locks and blockages. They can cause the fans to stay on.

How do I bleed out the air locks though?

There is no apparent air bleed valve on the engine?

As the title states, in normal driving conditions, does your electric fan generally run most of the time when at stand still at traffic lights in good old Sydney traffic?

Yes. The low speed part of my thermo fan failed and the temp gauge used to go up to 3/4 on the gauge, the ECU the apparently turned on the A/C fan and it dipped back to normal - and then cycled again. I replaced Temp sensors, thermostats and radiator caps etc and it made no difference - I then used the workshop manual to jumper the relays so that the low speed thermo fan also activated the A/C fan - Dah Dah - the car kept very near to normal temp - but you could hear the fans running at the lights - and feel the hot air with the windows down - in high ish 20 odd degree Gold Coast Temps the fans went on and off about every 90 seconds at the lights, above 30 on pretty much all the time.

Ok, when u refer to 'low speed thermofan' do u refer to the fan which runs independently from the a/c OR does this fan have 2 speeds (low and high speed)?

The way mine works is that the first thermo fan turns on when it hits one notch above half way and the a/c cuts in when it gets to 2 notches above half way on the temp gauge...when both fans turn on, it draws the heat out very quickly.

Ok, when u refer to 'low speed thermofan' do u refer to the fan which runs independently from the a/c OR does this fan have 2 speeds (low and high speed)?


The Engine fan (ie: not the A/C one) is 2 maybe 3 speed (I forget), I was finding that when the temp got to 2 marks above half the ECU turned on the high speed part of the main fan and the temp would drop back to normal. Jumping the activation (I used a diode to stop any feedback) to the A/C relay fixed the problem.

I've come to the conclusion that i have a potentially blocked radiator, what radiator flush should i run?

Update time.
I dropped the coolant and replaced it with nulon coolant and mixed 50% concentration. I drove it but I think the fan is still running more than it should as it seems the engine might be running hotter and maybe the little fan can't keep up...is this a common issue with the tj magna (mine is a ralliart)?

I also noticed under the bonnet that relay 'G' was missing and seems to be 1 of the 3 fan relays required so I pulled out the Parker light relay and placed it in relay 'G' plug...see if that makes a difference

I should also note that I removed the 2 bungs from the block and removed the radiator which seemed clean inside and thoroughly washed the outer fins

Here is a pic of the missing relay - do I need a relay in slot 'G' as it looks like it controls 1 of the 3 speeds? I just removed relay from slot 'A' and placed it in 'G'...
http://i59.tinypic.com/1ywapj.jpg

Reason your fan runs too much is that 50% is way too much for the small thin cores of the radiator to allow proper flow. Thin out back to the recommended 33% and this should assist

Before I did the flush, I was only running 1ltr of coolant concentration and it was running warmer on this mix so I don't think this is the issue, this is why I bumped it up to 50%. As per your recommendation though, I will bump it back to 33%...I just can't understand why the thermofan runs so much and temp climbs 1 notch above half? To say I'm frustrated is an understatement.

How about the missing relay for slot 'G', is that a requirement?

I also replaced the thermostat a few weeks with a genuine Mitsubishi and I actually pulled it out yesterday as it only dawned on me that the jiggle was facing down, now it's facing up as per workshop manual.

Think about it, and I have seen this so many times

The coolant is a thick liquid, not like water. When you have too much the flow of coolant slows down and the engine does not cool as efficiently

You may also have issues with the thermostat BUT you need to fix the obvious issue before you go start on other things

Magna's are more tollerant to too much coolant, I had a mate with an AU falcon, got it back from a local gas place here where I am located and they had used approx 50% coolant, the car was actually overheating on hot days to the point he would stop and let it cool down, we just dumped the radiator and replaced with straight water (given the block was still full) and problem solved that easily

wow - i definitely believe you & i will dilute the coolant and report back.
the thermostat is brand new, i was thinking if this was faulty, mmmmm....should i maybe pull it out & test it over a pot of boiling water as it states in the manual that it should open 8mm once it gets to 88 degrees which theoretically is just before the water starts to bubble on the stove? i think i also need to buy a thermometer to test it accurately.

Genuine or aftermarket thermostat

genuine from mitsubishi - when i bought it, the rep asked for the vin number to ensure its the correct item.
its only a month old.

Should I test the thermostat as I was told the genuine items are reliable?

update time.

i diluted the coolant from 50% to 33% - i guess there is a difference but its only marginal as i'd expect.

i then ran an electrical test on the drivers side fan (as per workshop manual) which has the plug with 4 terminals & all 3 fan speeds work (i.e. low, med, high)

i also ran a test on the relay box (as per workshop manual) & can also confirm the following results:
when i bridge low speed relay harness & supply power = passenger side fan activates
when i bridge med speed relay harness & supply power = drivers side fan activates
when i bridge high speed relay harness & supply power = both fans activate

does the above net the correct results as it seems to me that the electrics are in good working order?

Is there any way to check if the radiator fan is dead?

I've just finished putting a new radiator in and noticed the fan was loose in its housing and the fuse was blown. I sorted the fan out and replaced the fuse but it's blown again. I'm thinking the fan is stuffed

Take it to an Auto Leckie, coming into Summer you need the cooling system working properly ..... don't muck about with it.

When my fan stopped my Auto Leckie put a 2nd hand one in and it went for at least 100,000kms as I sold my old TH. Cost was well under $100.

Took my chances and picked up a second hand fan out of a 2001 Magna on gumtree for $10 and another fuse.
Fitted them this morning and all good now. The other fan motor obviously was rooted.

Thanks for your suggestion prowler