Overheating GUs

[4by]

Start with the easy and cheap options if it dosen't work then look at the other options.

1. Replace thermostat
2. flush radiator inside and out (pull it out and get it clean by a radiator shop)
3. rebuild visco hub at least 2 tubes of silicone oil don't buy a new one they pull apart ($10 a tube from a toyota dealer)
4. New coolant

Cost under $200

Good idea although I never thought a reasonably late model car would have overheating issues.

I think I'll also invest in an exhaust temp guage to check and monitor temps as I've had turbo/fuel/exhaust mods done.

Anyone know where I can buy a cheap exhaust temp guage from?

[GU Junkie]

Hey Damo (or anyone)

I was told some time back that when the viscous fan cuts in it
is fairly loud and obvious. However today a mechanic said he did'nt
think it was that loud. Can you tell me if I'm on the highway at say
110km/h will I here it cut in

Cheers Shaun

[rvh96]

the viscous fan will overun at any speed above approx. 80km/h as the air pressure going through the fan will overdrive it. Which is the whole priciple behind the clutch/viscous fan to reduce drag and power drain. A vehicle doesnt even need a fan at these speeds. The viscous fan only operates at low speeds and rpm.

[manno74]

As stated, you won't hear the fan at highway speeds - even if it did work, which it doesn't.
The problem isn't limited to 4.2s... I've had the problem a couple of times (ZD30 5spd) - flushes, checks etc found no fault, but it didn't cook every time anyway! Damn thing is more fickle than my missus!
Doing engine change soon (V8 Chev), and because of these problems discused, I'm looking at changing to 3 core radiator as preventative action. Maybe even thermo fan(s) too.

[GU Junkie]

Thanks guys,

I've obviously been given wrong info previously.

[Bingham]

bucket boiled going up toowoombah range---> temp runs fine until loaded up!!!

going to doctors on fri!!!!!!

mark

[raptorthumper]

Just asking. How do you know it boiled. Was it definately spewing out coolant from radiator overflow hose and making lots of noise.? Just don't want a simple faulty gauge or sensor to be inadvertently missed.

[Merv]

I have had similar problems on my TD42.

Going up steep hills, towing trailer, beach work would all see the guage creep up to 3/4 (Normally sits just below half) . Has never actually boiled, however is a pain in the arse when the aircon cuts out in 40 degree heat.

The first time I had this problem in 2001 I cleaned out all the mud caked in the radiator fins. This helped MOST of the time. A year later I pulled the radiator out and took it to a Radiator specialist to have it 'rodded'. Problem solved for 2.5 years.

In 2005 it started it was starting to get hot again, and as we were doing "the big trip" and towing the camper trailer I decided to get it rodded again before we went. Problem was, when the rods were going through they pushed holes in the aluminium as it ws getting too thin. I put a new radiator in and never had a problem the entire trip whether up hill, 40 degree plus, on beaches etc, guage never moved and aircon stayed on.

A couple of weeks ago we were heading out to kalgoorlie towing the trailer and bugger me, aircon turned off, guage had climbed ever so slightly.

I am pulling the radiator out and will be getting it rodded again.

My conclusions after talking to a number of experts are the radiators have very small tubes in them and can become clogged very easily, getting them rodded will fix this. They also seem to corrode fairly quickly, cant work out wether it is crap aluminium or electrolosis though.

It is a 98 model NA TD42 with standard gears and 33" tyres. Now with 280000km on it.

Hope this helps.

[Bingham]

Just asking. How do you know it boiled. Was it definately spewing out coolant from radiator overflow hose and making lots of noise.? Just don't want a simple faulty gauge or sensor to be inadvertently missed.

first thing is gauge climbs up to about 4/5 not evenquite into the real hot section.... but you can smell it then pop bonnet and she bubbles away and spews out...... but boiling glycol is not a pleasant smell and is easily detected.......

will let you know result on fri!!

[bogged]

A year later I pulled the radiator out and took it to a Radiator specialist to have it 'rodded'. Problem solved for 2.5 years.

What is Rodded?

[patrolmad]

I dragged my Jayco camper (1.25 tonnes loaded) up to Waddy Point at high tide two weeks ago and the gauge never went past 1/2. 3.0 manual. With roof rack and full load going up Toowoomba range the gauge hardly moves.

[Merv]

What is Rodded?

When they push a thin rod down the tubes in the radiator. To do this they take the top and bottom tanks off the radiator first.

[dirtyGQ]

mate i finally bit the bullet a few weeks ago and bought a brand new radiator in my td42 patrol ,before on mountain ranges etc it got to 3/4 temp max. Now doesn't even move these radiators get clogged easy as so get them flush as well as the block very regulary. Also use a quality coolant with a high glycol percentage i use "tectaloy extra cool gold" the gq capacity is aprox 13ltr's so i used 2 bottles.

[sld86]

Have been having this problem in my gq lately 4.2d. Have tried all the easy fixes so far-new radiator cap,thermostat,some radiator flush from autobarn and i just got a new waterpump in it today after it shit itself yesterday. Just had pyro fitted and with aftermarket turbo and 16psi without a cooler after pushing it only for a few hills with 35s on it ive only got it to about 450degrees, but after exhuast temp has cooled and drivin sensibly for 10 minutes on the way home i get there jump out and when it turns off i can hear it bubbling in the overflow but hasnt spat any out for a few weeks?? got me confused this one and the radiators full??

[bogged]

What is Rodded?

When they push a thin rod down the tubes in the radiator. To do this they take the top and bottom tanks off the radiator first.

wasnt sure if it was internal or straightening the fins on the outside..

thansk

[RaginRover]

mate i finally bit the bullet a few weeks ago and bought a brand new radiator in my td42 patrol ,before on mountain ranges etc it got to 3/4 temp max. Now doesn't even move these radiators get clogged easy as so get them flush as well as the block very regulary. Also use a quality coolant with a high glycol percentage i use "tectaloy extra cool gold" the gq capacity is aprox 13ltr's so i used 2 bottles.

Maybe you guys should look at getting some of those radiator filters for your top hoses, they have a small stainless steel screen to block the particles that block radiators - they used to be $40 have them on all my cars, amazing to see what comes out of the block and gets trapped there

Tom

[Bingham]

"mr bingham we couldnt seem to find a problem but we have had a few with the viscous fan play up so we fixed that, test drove and ok"

well fark me if on the back way up buderim i didnt gas it on all 3 hills and wallah boil.......

so the mystery continues.... they also said they have another 3l o1 or o2 there with exploding pistons but assure me the prob has been fixed!

[sudso]

When I had the radiator replaced in my Falcon they put a "large tube" radiator in.
About twice the size of standard radiator tubes.

No blockage problems since.

Radiator tube blockages are a main cause of over heating when everything else seems right. After very few years of manufacture the casting sand used in making engine blocks breaks down and thats a major contributor to radiator blockages.

Power backflush once a year by a radiator joint

Correct mix of correct coolant

Drive into wind on 40 deg.+ day, all day with a/c on and the temp never got over half on the guage.

[Gollywog]

Has anyone had success with the PWR replacement radiator, i believe it's alloy and 3 core. It should help, should hold 33% more coolant.
Mine's gotten warm on one occasion, 38 degrees on Stockton, changed the thermostat and been fine since.
Still upwards of a $1000.00 fix on what seems to be an Nissan oversight.

[bogged]

Has anyone had success with the PWR replacement radiator, i believe it's alloy and 3 core. It should help, should hold 33% more coolant.
Mine's gotten warm on one occasion, 38 degrees on Stockton, changed the thermostat and been fine since.
Still upwards of a $1000.00 fix on what seems to be an Nissan oversight.

2 blokes on Exploroz that are tourers, ones GU is 4ton loaded has one in his, but has also gone with aftermarket turbo which helped. He said the PWR helped, but its also a lot of $ to spend to find out that it doesnt work for u.. the other says his has worked.

one bloke went the MTQ turbo setup on his TD6 and his EGT dropped 100 degrees and more power.

I think others have mentioned them before in other threads, think the final result was 50/50

[speed=t/d]

I'm no expert but no one has mentioned the fact that Nissan upgraded the radiator in the 4.2 TD6 (2003) to a bigger one (I think the one used in the petrol 4.8) for this very reason. Maybe this is a big hint to pre 03 Nissan owners from Nissan???They wouldn't do anything for nothing...cheap arse bastart..rds.

[4by]

Some ideas for someone to try. My car is a GU 4.2 turbo diesel with 3" mandrel bent exhaust and 35" tyres.

I've just got my car back from Turbo Engineering where I've been discussing my overheating issues and performance.

They put the car on the dyno and evaluated the airflow into the engine. First thing he said was the patrols come with foam around the radiator and to remove this as it doesn't allow correct airflow. The foam at the bottom of the radiator was the worst as it prevented muddy water from falling out the bottom after a bog hole run. This was evident with my radiator as the bottom 30% was blocked.
Once he removed this correct airflow increased dramatically. Also all the lights, bullbars, and accessories infront of the radiator does prevent some airflow.

He then checked my fuel pump and found it was overfuelling. So he correctly adjusted the fuel pump and turbo which should also help prevent overheating. He put the car under load to test the overheating and it now operates alot cooler. Also the engine shake when cold is now gone as this is fuel pump related.

I now have extra kw and more torque and drives alot better. These guys did a great job and I have far better results than my last dyno experience. Just have to wait for a hot day and give it a test.

[GQTrav]

I recently fitted a PWR radiator to mine (it's a GQ but it's the same engine, TD42 with aftermarket turbo) and it made a huge difference. With my old radiator, even just after it had been taken out of the car and cleaned properly, the Hill just out of Marysville heading towards Big River I would have to back off when the temp guage hit 110, with the new radiator, i couldn't get it over 90.

[Troll00]

Found mine over heating again on new years day heading to Mann river going up the Cunninghams gap range then all the way to Mann River on every hill (hot day) came home Monday via a different way (cool day) didn't move the gauge once.
Had a mechanic check it out found it was the vaccum hose on the waist gate had a pin hole in it. Will run it again on the weekend with the trailer on to see if it fixes it.

[SilverBulletBM]

wow old thread.
I have a 02 4.2td completely stock with 213000k. No exhaust, no snorkel, nissan bullbar, steel/wood tray, 31's. Went up the beach just before christmas, not really a heavy load, just tent and food for 2 days. Didnt let tyres down. Went for a drive and found myself gassin for mayb 20k's on the soft stuff, speeds at 30kph MAX. It started to get hot, lucky i caught it. I pulled over, cranked the Heater on with fan speed for and it went back to normal in couple of mins.
The 2 reasons i see it overheating are, I was full boost for an extended period of time (its bout 9psi) and there was very little airflow through the radiator. The full boost creates excessive heat and minimal airflow doesnt allow radiator to get rid of it.
On the way back i didnt get up it as much, left the heater on with windows down and it stayed at normal temp. I dont believe they these vehicles were designed to run high boost at slow speeds for big periods of time. At the same time i believe that it is something that nissan should have looked at, but its now something i have to fix.
I will be gettin snorkel for cool air in (turbo kinda wrecks that), dump and exhaust to try and get some of the turbo heat out there, get injecotr pump timing checked, intercooler to try keeping air inlet temps cooler, pulling radiator out to clean out properly, and i will try and keep the grill clear (tho i do want a winch).
Has anyone found a fix for this problem since 2006? Anyone started with a untouched/unmodified 4.2TD and added things til it overheated?

[Troll00]

I have all of that on it and more you can fix it for a while then it will come back, my next option is to go bigger radiator.

[bogged]

At the same time i believe that it is something that nissan should have looked at

why? they dont know what mods people will run.. they designed it to be fine off the showroom floor, which in a sense is all they would be thinking. Once you start moddin its your problem.

Heres my rad the first week I had it, I thought I'd just see if there was any crap in the rad

[Bingham]

managed to get my new 06 auto 3l to boil again in the soft stuff again at double island... (it never seen mud)... granted i was flogging shit out of it for a reasnoble long period in soft stuff....... but would like to think cars made for tough aussie conditions could handle it... no trailer on for the record..

am absolutely baffled how people town big caravans with these machines. I suppose if your happy to sit on 80 Good truck but just think they need to slightly over engineer them not just to the line!! then that will do.

[bigbluemav]

so hes selling you $4k of gear which " will fix all your probs" and he has "has great success"...

He's not selling me anything. This is what they say will fix the problem. If they have experience in this, then I imagine they know what they are doing.

What do you think I should do to fix the problem?

Start with the easy and cheap options if it dosen't work then look at the other options.

1. Replace thermostat
2. flush radiator inside and out (pull it out and get it clean by a radiator shop)
3. rebuild visco hub at least 2 tubes of silicone oil don't buy a new one they pull apart ($10 a tube from a toyota dealer)
4. New coolant

Cost under $200

This (above msg from Troll00) is the best advice to initially deal with ANY overheating problem. Since I boiled the motor in a Surf 9 years ago, when I buy a car, I ALWAYS do this and do it as a matter of course EVERY 12 months.

My F.I.L. has similar issues with a 4.5 petrol 80 series and I suggested he do the same things (less the viscous fan)

The only thing that would be worth looking at is replacing the water pump in case the impeller is corroded away, if its not, just keep it as a spare. And something I have always done, that the nit pickers may nay say, is to use mid range price, premixed coolant and add one tin of the thick green concentrated shit.

I realise that it increases the percentage of ethyl glycol and this may be bad (corrosive if too concentrated??), but in the three cars (1992 Surf 2LT-E, 1984 Hilux 2L and Maverick TD42) that I've done it in, combined with yearly radiator (out of car) and engine flushing, changing of thermostat and coolant, none have had issues with overheating or cooling systems.

[maccapacca]

Sorry to bore with old problems but after looking at old posts does everyone with overheating probs with a td42 have post or pre 2003 Patrols as I was talking to an old fella today who has a 2003 factory turbo with 3" exhaust and a bit of a tweak. He tows a 21 ft van and has had no probs at all. Looking at the radiator it appears to be a lot smaller than my '99 which up until a few weeks back had the standard wide factory rad. I now have a Aussie Desert Cooler alloy and still have problems up long grades although not as bad. I tow a similar sized van. My engine is factory N/A with DTS turbo(12 psi) 3" all the way through and DTS top mount with 9" thermo blowing all the time on top. Pyro temps top 500-550 max. full load. In other words we would both have similar settings. Airflow through the grill appears to be the same on both vehicles. How did Nissan get away with a smaller rad in the '03, there must be something different in the engine itself. Any thoughts appreciated.