Overheating! Caused By Lowered Rad?

[huzzer 0]

Have finally got my track based Mi16 on the road!

 

It seems to go very well and all the gauges read as expected. However, when sat not moving in traffic or parked and idling the temp rises quickly even with one fan running constantly, the stop light and the water temp warning light come on. I have another fan that is switched on the dash which then brings the temp back down. Normal fast road driving does not cause any temp problems.

 

I'm worried that because the rad is lowered that the hottest water is maybe staying in the head and not efficiently being cooled by the rad?

 

Anyone come across these symtoms before?

[sutol 0]

NICE truck

[huzzer 0]

Thanks Sutol. Its a beast! Tediously slow but it I love how high it sits. Makes you feel invinceable! Drove it down to Turkey last summer, slept in the back. Would love to rover V8 it but the track mi seems to be taking up all my time!

[Baz 421]

Wouldn't have thought lowering the rad would cause any issues, plenty of people run similar setups, i would check other things first, the thermostat failed shut?

[sutol 0]

Thanks Sutol. Its a beast! Tediously slow but it I love how high it sits. Makes you feel invinceable! Drove it down to Turkey last summer, slept in the back. Would love to rover V8 it but the track mi seems to be taking up all my time!

 

Mines a lot older but the 2.8 turbo diesel helps it along a bit

 

And it's fantastic for towing .

 

[huzzer 0]

I think I have a spare I can try. If not how can I test for the thermostat? remove it completly just to test? I doubt I'd get a good seal like that though. ???

[huzzer 0]

Mines a lot older but the 2.8 turbo diesel helps it along a bit smile.gif

 

And it's fantastic for towing .

 

Looks good.

 

 

I searched for ages for a 2.8 but there didnt seem to be any suitable ones locally. TD would help too! It definately needs a kick up the backside when accelerating! Having said that, the 2.4 in this is very torquey, had no trouble pulling a 3.5t trailer out of the sea on shingle!

[Baz 421]

Remove it and see if it's open or shut, test it by putting it in a pan of water on the stove, and see if it opens!

[huzzer 0]

Thanks Baz. Good thinking!

 

[inferno 1]

Is it actually overheating or could the temp gauge be knackered? does the fast speed fan go on on its own? the cowling around the fans actually do a good job of directing airflow, so if you have chopped it out you could try a fan from something like an RSturbo, there very slim and easy to mount.what rad did you use? has it got the right fan switch?

 

if the thermostats shut, the rad wont get too hot, so i cant see the fast fans cooling it down significantly better than the slow one.

[huzzer 0]

The slow fan runs on its own. The faster fan runs from a switch inside. Does that mean that its normal for the slow fan on its own to not sufficiently cool the rad?

 

I believe the temp gauge to be functioning properly.

[huzzer 0]

For Sutol

 

[inferno 1]

on my zx turbo the slow fan wasnt enough to keep the temp down on idle on a hot day. although never had a gti like it. silly question... is the fan running the right way if yourve messed with it? ive seen that before...

[huzzer 0]

I havn't touched any of the wiring from the slow fan but its definately worth checking! Its good to know it does happen to others aswell just thought it was odd. I can control it with the fast fan switch but this is far from ideal as I can't reach the switch harnessed in! Today was my first day of driving it so I didnt let it get too hot, as soon as the stop light and warning light came on I ran the fast fan. I don't know how far it would have gone if I hadn't, I don't like the stop light coming on though!

[inferno 1]

id try the fan switch first tbh and check the fans move freely when off. the high speed should come in well before the red light.

[huzzer 0]

The high speed fan is manually switched.

 

How can I wire up the high speed fan to run automatically?

[sutol 0]

For Sutol

 

 

Luuuverly

Do any off roading in it ?

[welshpug 1,627]

run it in parallel on one speed and inline on the other.

 

make sure that the earth behind the l/h headlamp is good, mine was corroded and the slow speed was very slow until i cut the old earth block off and bolted a decent ring terminal on there, no problems with heat since

[inferno 1]

Does your fan switch on the rad have 2 pins or three?

 

if theres three it has 2 temp settings, low one for slow fan. without seeing how yours is wired up i couldnt advise how to fi it... but you could scan the haynes for a diagram and check its not been messed with too much.

 

theres also a possibility the slow fan circuit is wired onto the higher temp side of a 3pin switch.

 

or it could just be a thermostat:P ive never had a dodgy thermostat though... does it overheat with the heater blower on full blast?

[huzzer 0]

does it overheat with the heater blower on full blast?

 

 

Dont have any interior so cant run heater.

 

I believe it has three pins, Only two of which are being used (I think)

 

theres also a possibility the slow fan circuit is wired onto the higher temp side of a 3pin switch.

 

That is also a possibilty, good thinking.

 

Will test out all these theories tomorrow. Will keep you updated. thanks for the help.

 

Sutol. Not much off-roading in a serious sense, just round the building site and on the beaches in Turkey!

Would love to get into some but time vs money vs other projects prohibits. Am moving to Perth, Australia in August so i'm sure i'll be able to get into it bigtime. All the hilux's out there are petrol V6's and King cab which is a good combo for these.

 

Do you do any playing in yours?

[huzzer 0]

Sorry Welshpug, I seem to have scrolled down too quick and missed your reply!

 

That is a strong possibility. I remember when replacing the wiring not having a ring terminal on it. I shall check it out. Avatar looks cool, one of your own design?

[sutol 0]

Do you do any playing in yours?

 

Been over a few grass verges and towed my 205 on a trailer over a muddy field. Apart from that I just intimidate drivers of small cars, really need some air horns and open exhaust stacks and side steps and a roll bar and some more lamps etc.