TD42 T Gets real hot but only when towing

[NFG4X4]

Happy new year all fellow Patrolers, Guys iv got an obvious question, my deisel gq 4.2 runs 12pound boost with a factory radiator GU top mount cooler and ED falcon twin thermo fans! The thermo's always work a treat and i have never been anle to get her past halfway on the heat guage when in the scrub and city, however i towed my 1400kg caravan at xmas and she heated up something shocking, regardless of up or down hill at 100 she sat just off hot at 110 she would hit the H line so id have to back off, i was a bit slack before xmas and was only running water in the radiator which i know wouldnt help but i dont think coolant would have made a massive difference! Should i look at updating to a 3core alaminium rad or something as i have big plans with towing the van around aus and so on and dont want the damn thin heating up, especially cos power wise it toes fine! Anyone been here before? Cheers guys. Gardy.

[YNOT]

With your towing plans I would definatley be upgrading the radiator, also replace the thermostat ASAP and get the proper coolant mix in.
Check the A/C condensor for debris in the fins.
Make sure the radiator is sealed around the sides and bottom so all the air entering the front of the car is forced through the radiator.
My own personal opinion but I'm not convinced ED electric fans flow as much air as the factory engine driven fan with a fully functioning hub.

Tony

[Ben-e-boy]

are you towing 5th gear??? if you are, keep it under 100 and dont tow in 5th!!! drop it back to 4th, keep in the peak torque range. and get a pyro gauge you'll learn to drive off it


Ben

[Dark 1]

are you towing 5th gear??? if you are, keep it under 100 and dont tow in 5th!!! drop it back to 4th, keep in the peak torque range. and get a pyro gauge you'll learn to drive off it


Ben


Second that.

[MQ MAD]

A few questions
Why the thermos ???
Was the cooling system effecient before they were fitted ???
The factory fan flows more CFM of air than thermos,would this be the prob ???
When was the last time the radiator was properly cleaned ???
(Not with a hose properly rodded out by a specialist )
1.4 T should do it all day without a sweat

[NFG4X4]

Hey guys thanks heaps for your replies, and as for the 4th 5th gear thing yes i knew that and have a pyro and towed in forth only resting her in 5th down hill etc and as for the thermos they were actually on the car when i bought it, the previous owner said she used to get hot in the scrub and when he fitted these it fixed all the overheating problems so i just ran with it presuming twin thermos would out perform a stock engine fan!
As for a good flush it is on the cards for this weekend so ill let you know how much gunk was in it if any water water-coolant is always clear and clean.

[MQ MAD]

Not really so much by the water colour that tells wether the radiator if full of gunk
It blocks the cooling fins,which restrict it

[tkn]

Two or three maybe not so silly thoughts -
1. How clear are the fins in your radiator?
2. How clear are the fins in your air conditioning radiator?
3. Is there anything in front of your radiator e.g. large driving lights, winch, etc.?

The fourth is a nit of a longshot - is there any blockage(s) in your intercooler hoses or the cooler itself?

[diosky]

i'm from the philippines and was wondering how radiator fins are cleaned in australia? here it's taken apart and manually removed of its gunk with a piece of thin metal rod.

[Velty]

Hi guys, I'd like to add my views on the TD42 cooling issues.
I'm a diesel fitter & there's very little I don't know about these great engines.
I built my own engine for my 03 GU wagon. It pumps out 200rwhp running 20psi boost.
Every component in the cooking system is new, including a 3 row radiator & a trod on high flow thermostat.
I fitted the water pump with no gasket to minimize clearance for cavitation.
I towed my camper trailer to Victoria this Christmas. It was a 40 degree day down the Hume & mine truck got hot. It had never overheated with the ZD30 engine fitted.
As soon as I backed off it would cool back down.
This was happening with exhaust temps only at 450.
I did lots of thinking & came to the conclusion that it's combustion temp in the head, rather than an inefficient cooling system that causes this widespread problem.
Not enough coolant circulates through the ferrules in the head.
I removed the head & tapped a 3/8npt thread in the rear into the water jacket between the welsh plugs.
I fitted a 5/8 barbed elbow & ran a hose straight to the header tank.
Once I started her I could instantly see an increase in flow through the header tank.
I hooked up my 2 ton boat & hit a big hill. Egt 550 & temp didn't rise.
Problem fixed.
I know it's a pain in the ass but an overheating system reduces engine life so it's well worth the effort.
I hope this might give y'all some ideas.

[growler2058]

G'day Velty welcome aboard mate. Excellent mod mate well done! Jump over to the intros mate so the other members can say g'day and let us in on any other trade secrets ay ;)

[Ade]

Gday people,

I kinda agreed with Velty.

I cracked my old motor pre combustion chamber, all of them and now I had this turboed stock motor and ip for about a year or so with 15psi boost. I had no issues with overheating since with this motor no matter how hard I trashed it but not on a long pull up a steep grade and hills. I found that ect are very related to egt at least in my case. On a heavy load on that hill my egt will only max out to 680c pre turbo but with that egt my ect will be around 110c. Bringing down the egt to 540c will bring down the ect to 100c. All these while I am ok with it. But I wanted a worry free driving up that hill, without need to keep an eye on the gauges.

Last week I started playing around with the ip max load screw. Instead of tweaking it up I had it down to about a quater turn from the stock setting. As expected less power but so did the egt and ect. Speeding up wot at that same hill my egt now will only max out to 480c and ect at 82c. How bad was the power lost..well it's an auto. 1st & 2nd gear will pull up close to 4000rpm no problem just slower. 2nd gear will pull up to 4000rpm and speed is about 90kmh. Continuing wot on 3rd gear will be a struggle to get it up pass the 3000rpm even on a flat road.. :( Maybe a good i/cooler set up will let me stayed with the stock ip setting.

By the way, she's a pretty heavy trol with diy drawer slider bars winch etc, 315/75 with 4.6 diff. F/consumption was about 20l/100km. I cannot tell if she had over fuelling or what with the stock ip setting. There was no black smoke only a slight puff on a hard pull.

I will stick around with this setting for a while a see how she goes on f/c and off road with that. If really needed, I will slap in a fmic and that head drilling mod.

Ade

btw, both motors are TD42 silvertop

[Ade]

Theres another point, few weeks ago I got my hands working on my brother's trol wacking in a turbo to his silvertop. With his stock ip and same turbo spec as in mine, his trol power were so much less than mine with the stock ip. I had to turn his max load screw up to half a turn just to get the power as in mine with quater less turn on the max load screw. His trol were struggling to pass the 3000rpm on a 4th gear. He had no overheating issue with this set up so we will stick with it atm.

So there you go..two so thought stock ip with different out come.

Ade

[MJP74]

Has anyone tried one of the cooling system cleaning additives with this problem? Supposedly clean the rust and gunk out of the radiator and motor. I have done the following and still have an overheating issue when towing:
Thermostat replaced, radiator cleaned and tested (twice), water pump replaced, fuel mix checked and adjusted by the guys who wound it up (also have a larger exhaust fitted by them), viscous fan hub and fan blades replaced, Silica added to the viscous fan hub. Then replaced the thermostat and radiator cap again with Nissan parts just to be sure (76.5 degree thermostat) and added a water temp gauge to check the temp rather than relying on the cluster gauges.

Running out of options and looking for any words of wisdom!

[Warren Maxwell]

Hi. Fuel Mix,??? Leave it alone standard fuel pump. IT WILL NOT OVER HEAT. wazza.

[MudRunnerTD]

Has anyone tried one of the cooling system cleaning additives with this problem? Supposedly clean the rust and gunk out of the radiator and motor. I have done the following and still have an overheating issue when towing:
Thermostat replaced, radiator cleaned and tested (twice), water pump replaced, fuel mix checked and adjusted by the guys who wound it up (also have a larger exhaust fitted by them), viscous fan hub and fan blades replaced, Silica added to the viscous fan hub. Then replaced the thermostat and radiator cap again with Nissan parts just to be sure (76.5 degree thermostat) and added a water temp gauge to check the temp rather than relying on the cluster gauges.

Running out of options and looking for any words of wisdom!

You should install an Exhaust Temp Gauge (pyro) and a manual Boost controller and then have it dyno tuned professionally. You should avoid towing in 5th and avoid towing at 2000rpm. Better to change down and rev at 2500rpm. The TD hates 2000rpm.

[kbchez]

The only thing you have not replaced is the radiator. If some of the internal cores are blocked no matter what you flush it with won't unblock it. If you are really keen remove one tank off the radiator. With a lawnmower starter spring and garden hose carefully clean all tubes you be surprised at how much crap comes out.

[Hodge]

Better to change down and rev at 2500rpm. The TD hates 2000rpm.

Hey Darren mate. Are you saying this only when towing or in general? I cruise at 100km/h and it sits on 2000rpm, or just over in 5th. At that speed/rpm it has enough guts to cruise. But if i need more power to over take or something, I'd have to gear down to 4th. It just feels like its labouring.

In 4th, its 2400rpm or there abouts. It just seems like its revving too much if im in 4th crusing at 100.

[AB]

Hey Darren mate. Are you saying this only when towing or in general? I cruise at 100km/h and it sits on 2000rpm, or just over in 5th. At that speed/rpm it has enough guts to cruise. But if i need more power to over take or something, I'd have to gear down to 4th. It just feels like its labouring.

In 4th, its 2400rpm or there abouts. It just seems like its revving too much if im in 4th crusing at 100.

I would say only when towing mate for the load on the transmission at low rev's.

[AB]

Having saying this I try not to cruise or let the rpm go below 2000 regardless unless down hill of course.


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[MudRunnerTD]

Hey Darren mate. Are you saying this only when towing or in general? I cruise at 100km/h and it sits on 2000rpm, or just over in 5th. At that speed/rpm it has enough guts to cruise. But if i need more power to over take or something, I'd have to gear down to 4th. It just feels like its labouring.

In 4th, its 2400rpm or there abouts. It just seems like its revving too much if im in 4th crusing at 100.

Yeah certainly when towing. The 2000rpm Mark seems to not suit the TD power curve unless your running a 16g or something. For mine with the HT18 2000rpm was the Devils number mate. Cruising on flat road in 5th is fine. Trying to roll on hard from there or climbing a hill and holding 2000rpm spikes the EGTs badly.

Even with the Borg Warner tuned well 2000rpm is the wrong number. Towing was much more comfortable in 4th. I towed home from SA in 38d and saw the needle get to 2/3 but cruised at about 1/2 way. AC running and cruising at 115kmh. Dropping back to 100kmh and it dropped a little.

I need a new IC and I think my pump is at end of life.

The problem for unturned TDs and no gauge for EGTs is guys driving them bogged down at 2000rpm, EGTs rise and they have no idea. First they know Is the water temp rises and they are cooking.

A quality tune, turn the lights on by fitting a Pyro gauge to see what is actually happening and it's a great place to start.

Old mate has already spent a fortune and had a screw driver tune has no idea what fuel/boost he is running or what his Exhaust Gas Temps are doing. Buckleys chance of sorting it out.

[Hodge]

Yeah certainly when towing. The 2000rpm Mark seems to not suit the TD power curve unless your running a 16g or something. For mine with the HT18 2000rpm was the Devils number mate. Cruising on flat road in 5th is fine. Trying to roll on hard from there or climbing a hill and holding 2000rpm spikes the EGTs badly.

.

Yeah this is exactly what mine is like right now. And mines, even tuned with a big intercooler.
Has perfect amount of juice to just cruise on flat freeway @ 100 in 5th. But if I need it to get up and boogie in that range, while staying in 5th, EGT's inflate rather quick.
Any, even a very slight incline, I need to go 4th, otherwise, the motors labouring big time.

I suppose, it's better for it to rev higher, rather than cook.

[AB]

Slightly hijacking old mates thread but low rpm (below 2000rpm) on hills and flat cruising is putting undue stress on drivetrain and working harder along with water pump not pushing coolant threw cooling system efficiently resulting in higher temps.


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[GQtdauto]

Don't have a pyro just a factory temp gauge and a trannie oil temp gauge , it's amazing the difference labouring does to the fuel economy and the temps in the auto but after fitting the torque lock I haven't seen temps past 90 and no longer labour the motor if its a flat stretch I'll lock in OD at 2000 or if hilly or blowing a gale I'll lock in 3rd at 2450 for 100kph .

[AB]

So some feedback for heavy towing a TD42T in the heat.

37 degree day very humid towing 2 tonne full height caravan back from the border with decent hills with the GQ fully loaded with family, dogs and gear.

Averaged 90-95 degrees only sitting in 4th the whole way averaging 90km/h.

Temps did get to 100 a few times on hills and one time at 105.

I think in this circumstance it did pretty good but I also haven't blocked out the spaces on the top and side of radiator either.

[AB]

Forgot to mention AC running the whole trip.


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[Hodge]

I think in this circumstance it did pretty good but I also haven't blocked out the spaces on the top and side of radiator either.

And you have a front mount too don't you? This would also hinder some air going through the rad?

[AB]

Yes absolutely. EGT's were 250-300 and occasionally 350 max 400.


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[katwoman]

Katrol damn near boiled on Sunday towing an empty tandem ( yes empty). I think I'm going to start looking into better water pumps.


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[jff45]

So some feedback for heavy towing a TD42T in the heat.

37 degree day very humid towing 2 tonne full height caravan back from the border with decent hills with the GQ fully loaded with family, dogs and gear.

Averaged 90-95 degrees only sitting in 4th the whole way averaging 90km/h.

Temps did get to 100 a few times on hills and one time at 105.

I think in this circumstance it did pretty good but I also haven't blocked out the spaces on the top and side of radiator either.

Not too much different to mine but I was running on a 30* only day.

2.5t behind the TD42T up and back to Rainbow Beach 400 kms. Auto trans towing in 3rd with TCC manually locked, average engine temps in the high 80s with EGTs 300-350. Running 90-95 km/h with occasional 100 km/h on the flat.

Couple of hills I pushed it intentionally, still in 3rd locked, and it just powered up no problem. Temps hit 100 with EGTs just reaching 400. Both came back down quickly when I reached the top.
Also A/C running all the time.

I have a modded Rueben Bauer 11mm pump with Mamba 16G which ran 141.5 rwkw on the dyno in Caboolture.
I run a 52mm 3 core all alloy rad with stock water pump but 50 ml silicone in the hub and a G35 fan.

Fuel for the trip came out at 19.3 lt/100. Very pleased with it all..

[JackoGQYoot]

Hi guys
Is it normal for my factory temp gauge to read at about 1/4 - 1/3 all the time? Is this where the gauge should sit? The gauge also takes ages to come up after I start the engine. Any suggestions?
chrz

[Winnie]

Hi guys
Is it normal for my factory temp gauge to read at about 1/4 - 1/3 all the time? Is this where the gauge should sit? The gauge also takes ages to come up after I start the engine. Any suggestions?
chrzIt's normal for the TD42 to take a while to get to operating temperature.
1/4 to 1/3 is really good. That's where mine sits unless under load on a really hot day it can creep just past half way.

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[Rossco]

Yeah same, mine sits about there and is good & normal. Doesn't take to long to get warm, probably 5 mins is up to temp.

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[AB]

It's normal for the TD42 to take a while to get to operating temperature.
1/4 to 1/3 is really good. That's where mine sits unless under load on a really hot day it can creep just past half way.

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How long is a while?

Cold start up they can take for ever and a cold engine running is where most engine wear occurs.

If your concerned then check the thermostat is not stuck open.

I personally don't idle my car to get to operating temp as it would take upwards of 5 mins.

You want your engine to reach operating temp sooner rather than later without putting stress on it of course.

If you live on a hill going downhill to town then a huge win, idle for a minute or so and cruise down hill or after a minute idling use the throttle control up a little bit to say 1000rpm to reach temp quicker without load.

Edit: quoted Winnie by accident lol


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[mudski]

I could drive 15 minutes in mine until it gets to operating temp of circa 80c. This is with a cool but not cold morning and just driving around suburban streets. Cold mornings, below 10c forget it. If I get onto the freeway it will warm up much quicker. Leaving it idle it I would run out of fuel before it reaches temp. Lol.

[GQJames]

Second that.

I can confirm this to, 5th gear - you'll get hot. 4th gear is perfect on any (even slight) load. When going along the flat or down hill, I'll knock it into 5th.
I find, if egt hits 450 -500, start backing off then - if you want your temp gauge to stay under halfway..