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3.1TD Mu Wizard Overheats

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3.1TD Mu Wizard Overheats

Postby Arnolozz » Thu Nov 20, 2014 8:22 pm

Hi fellas,

New here, looks like a great forum with lots of resources.

For a while now (couple of years) my 1996 Mu Wizard 3.1TD Auto 170k kms on the odometer, has been getting hot (about 3/4 on the temp gauge) when the engine has been loaded up for a while, for example, going up steep hills or soft sand driving, etc. When it gets hot i just pull over and she will cool down. Driving around town or on the highway presents no problems and starts and runs fine.

I have recently fitted a transmission cooler as i read somewhere that the automatic can heat up the engine coolant so ive completely bypassed the stock setup now and it still gets hot.

Radiator had been flushed and cleaned earlier this year, new thermostat, ive even removed thermostat once and still overheats.

Midway through the year i replaced the turbo with brand new oem IHI, as it had a loud whine on shutoff. Stock 12psi boost and it still overheats.

Back in 2011 the fuel injector pump was rebuilt as it leaked, today i had the timing and fuel mixture amount checked by the same mechanic and he said it was fine. He mentioned that i could increase the boost to help burn any extra fuel if when it makes boost, i have tried this tonight and it made no difference.

Has anyone had this experience? Im running out of ideas as to what it could be.

Thanks in advance.
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Re: 3.1TD Mu Wizard Overheats

Postby nb422 » Thu Nov 20, 2014 9:32 pm

Potentially head gasket or cracked head with these engines. But have you checked that the viscous fan is functioning as it should?
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Thu Nov 20, 2014 9:39 pm

Thanks for the quick reply nb422

I've taken the car to a head specialist and he ran his diagnostics and said it isn't the head gasket or cracked head.

Viscous fan blows pretty hard at idle when hot. Radiator specialist said it looked okay to him.
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Re: 3.1TD Mu Wizard Overheats

Postby nb422 » Thu Nov 20, 2014 9:53 pm

How loaded up is it when it gets hot? Maybe the engines just under too much load for its liking, my 2.8 mu gets hot when loaded (like towing 3 ton worth of another mu and trailer its on lol)
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Thu Nov 20, 2014 10:02 pm

Gets hot with no payload. Just me in the car.

In my first post i meant loaded up as in the engine laboring for a while.
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Re: 3.1TD Mu Wizard Overheats

Postby geeves » Fri Nov 21, 2014 4:29 pm

Lay money on viscous fan. My Wizard did the same thing Open road speeds good as gold but stuck in slow traffic on a skifield road the temp went off scale. It did have an aftermarket grill on which got binned that evening and it was better but still overheating. When hot the fan turned easily by hand. New fluid in the fan and problem gone
Second option bad water pump. The impellor fins can corrode esspecially if you havnt kept the antifreeze up to spec This causes reduced water flow
third option bad thermostat ie not opening fully Easy to test in the wifes best saucepan on the stove
Otherwise advanced or retarded injection timing
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1TD Mu Wizard Overheats

Postby turnturn » Fri Nov 21, 2014 7:14 pm

Have you considered fitting an aftermarket temperature gauge to confirm that the temperature is getting into an area of concern?
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Re: 3.1TD Mu Wizard Overheats

Postby geeves » Sat Nov 22, 2014 5:40 am

for a temp answer try a touch test.
if you can hold your hand for more than 5 seconds on the radiator its about 80C (plastic tank) If your lucky enough to have metal tank this is 70C
Same on thermostat housing
If you can touch but not hold your hand on its between 80 and 100
at 100 to about 105 a ball of spit will evaporate in 3 or 4 seconds
above that it will boil quickly
at about 120 it will bounce off the surface
100 at the thermostat housing is pretty much as high as you want to go unless you are really working the engine. (80 to 90 much more reasonable) The radiator should not be this hot unless its not doing its job. You say it was flushed but the fins are not blocked with mud?
If the engine is hot but the radiator quite cold look at your water circulation (pump thermostat etc)
if both hot look at airflow
Whats fuel ecconomy like?
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Fri Nov 28, 2014 8:17 pm

geeves wrote:Lay money on viscous fan. My Wizard did the same thing Open road speeds good as gold but stuck in slow traffic on a skifield road the temp went off scale. It did have an aftermarket grill on which got binned that evening and it was better but still overheating. When hot the fan turned easily by hand. New fluid in the fan and problem gone
Second option bad water pump. The impellor fins can corrode esspecially if you havnt kept the antifreeze up to spec This causes reduced water flow
third option bad thermostat ie not opening fully Easy to test in the wifes best saucepan on the stove
Otherwise advanced or retarded injection timing


I just had the viscous fan repacked the other day. I also removed the nudge bar which had decent sized spot lights and drove it up the same hill and i think i can hear the roar of the fan. Temps did not rise like usual so maybe the issue is solved. I will take it up there another day to confirm this.

turnturn wrote:Have you considered fitting an aftermarket temperature gauge to confirm that the temperature is getting into an area of concern?


Yes this would be a good investment but i do not like extra gauges on the dash. Function over form though.

geeves wrote:for a temp answer try a touch test.
if you can hold your hand for more than 5 seconds on the radiator its about 80C (plastic tank) If your lucky enough to have metal tank this is 70C
Same on thermostat housing
If you can touch but not hold your hand on its between 80 and 100
at 100 to about 105 a ball of spit will evaporate in 3 or 4 seconds
above that it will boil quickly
at about 120 it will bounce off the surface
100 at the thermostat housing is pretty much as high as you want to go unless you are really working the engine. (80 to 90 much more reasonable) The radiator should not be this hot unless its not doing its job. You say it was flushed but the fins are not blocked with mud?
If the engine is hot but the radiator quite cold look at your water circulation (pump thermostat etc)
if both hot look at airflow
Whats fuel ecconomy like?


Thanks, i will keep this in mind next time. The radiator fins are pretty clean. Fuel economy is good, standard tyre size will give me approx 10l per 100km on the highway. Around down maybe 14-15l per 100km.
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Re: 3.1TD Mu Wizard Overheats

Postby geeves » Sat Nov 29, 2014 5:42 am

decent sized spot lights

I wonder how many cars overheat because of these? To get proper airflow round them there needs to be a decent gap behind them but there it no way to mount them that far forwards without breaking the law. Also the modern much smaller lights put out just as much.

ps can I sell you a set of 10 inch lights that were removed from my wizard 5 years ago. They didnt work anyway
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1TD Mu Wizard Overheats

Postby magicdeo » Sat Nov 29, 2014 10:14 am

If you have no success rip the radiator out and have a good look at it. I had this same problem with my patrol and when I pulled the radiator out the fins were very brittle and would break if touched and it was clogged up with mud, grass seeds etc. New radiator and she doesn't overheat no matter how hot it is or how much you load it up
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Re: 3.1TD Mu Wizard Overheats

Postby geeves » Sat Nov 29, 2014 1:47 pm

I had a radiator on my old bighorn that a quick look said was fine. It came from a wreckers with fresh paint. 3 months of overheating trying everything else till one day I took it out held it to the sun and saw nothing just black. Wreckers had painted over the mud
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Mon Dec 08, 2014 9:33 pm

So took the wizard up the hill she normally gets hot going up but this time the needle just went half way on a reasonably muggy hot day with the aircon on full cold. Im okay with this so i reckon she'll be good for fraser island this summer. So turns out getting the viscous fan repacked with silicon fluid solved this problem.

Thanks for your help guys
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Sat Mar 21, 2015 6:43 pm

Well 4 months on and the car still gets hot (about 3/4 on the temp gauge), before Christmas i changed the radiator because i saw some of the fins were corroded. I also thought the repack of the viscous fan fixed the problem but sadly it didn't. Went to fraser island over the xmas break and the thing got hot on the highway to and from the island. On the island it only got hot when things got boggy and got a little hot whilst traveling down the 75 mile beach rd.

Yesterday was a particularly hottish day here on the Gold Coast, approx 33 degrees. And it got hot on the highway sitting at about 110km/h with the aircon on full cold. Usually this never was a problem. So for the rest of the trip i had to crank the hot air and it would bring it down to normal.

Anyways im thinking about installing and EGR kit that comes with the sensor and gauge to monitor the exhaust temps, anyone know of a reasonably priced kit available? Maybe these temps are getting way to high causing the whole engine to get hot no matter how good my coolant items are. Pretty sure the water pump was changed at 100k kms when the timing belt was done, but i have to find the receipt and make sure. So apart from this every other coolant related item has been changed. Which leads me to thinking it might be a tune issue, which could be recreated on a dyno.

I highly doubt its a head gasket issue or cracked head, i don't loose coolant, i dont get any milkshakes in the oil, i had a sniff test done years ago and the pro said nothing is wrong with the head.
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Sat Mar 21, 2015 11:10 pm

So i found a receipt from back in 2005 saying the water pump was replaced at 120k kms. Car only now hss 170k kms on it. And i know it has had good coolant in it ever since.
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Re: 3.1TD Mu Wizard Overheats

Postby geeves » Sun Mar 22, 2015 5:42 am

Try running it without a thermostat for a few days. It does mean partial draining the system. If the thermostat is unknow condition it could be worth just replacing but test the old one anyway. Put the old thermostat in the wives best saucepan (not non stick) cover with cold water and heat on the stove When its steaming well it should start to open and be fully open before it boils.
Otherwise with the list of already vcompleted items tune is the best bet but also consider the gauge might be telling lies and its not overheating at all
Sanding your knuckles before starting work can help. That way you cant skin them
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Sun Mar 22, 2015 5:27 pm

Thermostat - i replaced this late last year so should be good

An external temp guage would be a good idea, just to know the real temps.
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Re: 3.1TD Mu Wizard Overheats

Postby Arnolozz » Wed Mar 25, 2015 6:29 pm

My office leases out our back office to Autoking and i had a good mate there have one of his boys look at it today. Water pump checks out okay, good coolant flow, max temp he got it to was 82 degrees. But he could not re-create my coolant creep, he did however manage to get the auto transmission overheat light to come on. Weird because i could never get it to overheat, all be it, he would of been stalling up the auto in the car park at work to load up the engine. Their recommendation is to hook up my transmission cooler in series with the stock radiator to help overall cooling of the transmission. They also think on the highway the external transmission cooler is getting too hot and is essentially blocking 40% of the coolant radiator with its hot air.

So i removed the external transmission cooler altogether because the oem setup did work in the past and drove around and i could still get it hot. I can re-create the problem off the highway now, i apply the brakes whilst accelerating to put extra load on the engine. After say 700m the coolant gauge will start creeping up.

Here's a pic. On left is where it usually sits & on the right is where i usually back off or maybe another needle width. Please excuse the t belt light, it was replaced at 100k kms but never reset the jumpers behind the dash.
Image
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Re: 3.1TD Mu Wizard Overheats

Postby geeves » Wed Mar 25, 2015 6:52 pm

Trans cooler series or parallel both work and in parallel there is less chance of blockage. Have to think about the airflow though. You never told us about the trans cooler. I would keep it though as it is much kinder on the trans. Having the trans fluid go through the radiator does warm the trans as well so you do need this. When cold the trans shifts harshly and costs fuel.
Have a look at the front of your car Make sure there are no gaps air can get round from the front grill area to behind the fan without passing through the radiator. It takes very little to lose efficiancy
Sanding your knuckles before starting work can help. That way you cant skin them
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