overheating td42 cant figure it out

[dakka1]

hey guys my td42 is over heating

with the aircon on and any sort of load on it weather it be labouring up a hill or over the 2000 rev mark. the other time it over heats is also with aircon on and at idle.

the viscous fan is locked up all the time and I have gone to a brand new alloy radiator. fan shroud is good and I have coolant. radiator cap brand new.
I pulled the thermostat and its stuffed Its locked in the open position. when I say in the open position when the thermostat is stone cold its still open about 5mm. I did the boil test and it opens about another 5mm so 10mm in total. not sure if this is enough???
when opening it pushes the bi-pass penny down and I feel it is enough to seal the bypass when in open position. feel this as when I undid the housing the car was hot and it pushed the housing of the car.

only other thing I am not sure about is ing is extremely rusty on the outside do these have a problem of eroding the impeller fins away?

apart from that im at a loss and hoping its just the thermostat isn't opening properly

any help would be great thanks

[Alitis007]

How do you know it is overheating from the factory gauge or aftermarket? ? Does the water get pushed out of the overflow bottle when it overheats??

If the thermostat is jammed open I would change that but an air lock will also cause it to overheat aswell. The water pump is not meant to have a gasket altho the aftermarket ones are supplied with one so you could remove it to inspect the impeller if you like and re seal it with Threebond or an equivalent sealant

[dakka1]

hey mate cheers for the reply,

I do still run the factory gauge and I know there touchy. but its not a nice feeling seeing it go up to 3/4 or more. the water doesn't get pushed out the over flow bottle but the bottle is always very full. ill be changing the thermostat tomorrow but I have my doubts it is the main cause as if it was stuck in the open position u would tend to think it would not cause an over heat. my only guess is that its not opening to full open. I did the boil test and its opening about 10mm or so and to me it still has room to open but doesn't get there. so im unsure

[Bloodyaussie]

I would be running a flush through that for sure then swap out pump and thermostat... also while you are at pull out the radiator and see if it is blocked.

[dakka1]

radiator is brand spanking new 3 days old

[Alitis007]

hey mate cheers for the reply,

I do still run the factory gauge and I know there touchy. but its not a nice feeling seeing it go up to 3/4 or more. the water doesn't get pushed out the over flow bottle but the bottle is always very full. ill be changing the thermostat tomorrow but I have my doubts it is the main cause as if it was stuck in the open position u would tend to think it would not cause an over heat. my only guess is that its not opening to full open. I did the boil test and its opening about 10mm or so and to me it still has room to open but doesn't get there. so im unsure

On the bench when you boiled the water how hot was the water? On the bench and in the car I would use a more accurate gauge for piece of mind coz these gauges are iffy at the best of times lol.

If it was staying open it can some times jam in the partial open position and affect water flow but let us know what happens after you change the thermostat

[dakka1]

yeah in the kettle it was virtually just before the water boiled that it started opening which is not right for a 76.5 degree tstat. the more I think about it the more I feel its the main cause. im going to reply the pump as well as the thermostat tomorrow anyway then Saturday I have about an hours drive out west of brassy to do so that will soon tell me if it has improved as well as idling in the driveway

[happygu]

My old 4.2 with aftermarket turbo would sit at around 1/3 on the factory gauge, but go up to 3/4 when pushed hard ...

It never actually overheated, but I would back off a bit and the temp would drop back nearly instantaneously

[dakka1]

when mine gets to 3/4 temp it takes for ever to come back down. I went up the beach at xmas and when it did it I assumed it was the radiator as it had a heap of fin rot. changed it to a brand new allow one and yeah still no change

[Stropp]

Make sure you bleed the system correctly with a cutoff coke bottle in the radiator with the car facing uphill to ensure you burp it properly to get all the air out.

[dakka1]

will do. ill let u guys know how I go tomorrow night after I get it all fitted up

[MudRunnerTD]

Make sure you bleed the system correctly with a cutoff coke bottle in the radiator with the car facing uphill to ensure you burp it properly to get all the air out.

With the heater on

[happygu]

hey guys my td42 is over heating

with the aircon on and any sort of load on it weather it be labouring up a hill or over the 2000 rev mark. the other time it over heats is also with aircon on and at idle.

the viscous fan is locked up all the time and I have gone to a brand new alloy radiator. fan shroud is good and I have coolant. radiator cap brand new.
I pulled the thermostat and its stuffed Its locked in the open position. when I say in the open position when the thermostat is stone cold its still open about 5mm. I did the boil test and it opens about another 5mm so 10mm in total. not sure if this is enough???
when opening it pushes the bi-pass penny down and I feel it is enough to seal the bypass when in open position. feel this as when I undid the housing the car was hot and it pushed the housing of the car.

only other thing I am not sure about is ing is extremely rusty on the outside do these have a problem of eroding the impeller fins away?

apart from that im at a loss and hoping its just the thermostat isn't opening properly

any help would be great thanks

I would put a proper functioning thermostat in and try again, as with the faulty one in place it may not be slowing the coolant in the radiator down for long enough to make sure that it cools down sufficiently to do its job.

[MudRunnerTD]

I would be running a flush through that for sure then swap out pump and thermostat... also while you are at pull out the radiator and see if it is blocked.

Didn't you read the whole thing Jonathan?

[Bloodyaussie]

Didn't you read the whole thing Jonathan?

?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ??obviously not??????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????/

[rusty_nail]

?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????????????????????????????????????? ??obviously not??????????????????????????????????????????????? ?????????????????????????????????????????????????? ?????????????????/

Meowwwwwwww

[Bloodyaussie]

Anyway enough from the children... look forward to a result mate.

I have been stuffing around with radiators and hoses and shrouds to sort a cooling issue myself.

After fitting a new radiator (copper/brass) after the crap alloy one was not up to the task... also ebay hoses that were swollen after only 1500km of use and also was instructed to get myself a higher rated cap at 15-16 pound.

Today I went to Healsville and on my return hit the big hill near Andy's for my first real test and with an ambient temp of about 26 degrees my coolant temps maxed out at 93 and my pyros hit 520 for only a brief moment.

Upon reaching the top all temps quickly came down... now many know this hill and is long and some sections steep and is a good test.

I have not checked my overflow bottle but before the recent changes my bottle would be over full.

The other test still to come is the long droning drive on the Hume hwy and a hot day... not sure what other get when doing that sort of driving.

[Winnie]

The other test still to come is the long droning drive on the Hume hwy and a hot day... not sure what other get when doing that sort of driving.

You'll find out on Aus day!

[Bloodyaussie]

I guess so Winnie.... I just went and checked and my overflow bottle has not moved at all.

I hope I have now sorted it.

[liftlid]

I've just been to coffs and back and egt regularly went to 550 and the water temp to 3/4 on hills under load and a loaded roof rack, both ways on the Hume . Back off and it went back to normal

[AB]

I've just been to coffs and back and egt regularly went to 550 and the water temp to 3/4 on hills under load and a loaded roof rack, both ways on the Hume . Back off and it went back to normal

I remember seeing a post from you about this the other day but can't remember what you said.

Has it always been like that loaded up 3/4 temp?

[AB]

Anyway enough from the children... look forward to a result mate.

I have been stuffing around with radiators and hoses and shrouds to sort a cooling issue myself.

After fitting a new radiator (copper/brass) after the crap alloy one was not up to the task... also ebay hoses that were swollen after only 1500km of use and also was instructed to get myself a higher rated cap at 15-16 pound.

Today I went to Healsville and on my return hit the big hill near Andy's for my first real test and with an ambient temp of about 26 degrees my coolant temps maxed out at 93 and my pyros hit 520 for only a brief moment.

Upon reaching the top all temps quickly came down... now many know this hill and is long and some sections steep and is a good test.

I have not checked my overflow bottle but before the recent changes my bottle would be over full.

The other test still to come is the long droning drive on the Hume hwy and a hot day... not sure what other get when doing that sort of driving.

Pre ic days I was exactly same egt on that hill and 550 on hot days.

[Bloodyaussie]

Pre ic days I was exactly same egt on that hill and 550 on hot days.

And what now.... most of it was 400-450 and only saw 520 for a moment.

[AB]

And what now.... most of it was 400-450 and only saw 520 for a moment.

My ic is working a treat.

Hot days this summer in 4th going up is 300 to 350 max on that 38 degree day.

[Winnie]

My ic is working a treat.

Hot days this summer in 4th going up is 300 to 350 max on that 38 degree day.

That's awesome Andy... Sounds like you need a new 12mm pump and turbo to bring those temps up a bit

[Bloodyaussie]

My ic is working a treat.

Hot days this summer in 4th going up is 300 to 350 max on that 38 degree day.

Cannot complain about that.... thanks to that monster ic..

[AB]

That's awesome Andy... Sounds like you need a new 12mm pump and turbo to bring those temps up a bit

Saving to put to put these lockers in and ratios.

Once done its pump and turbo

That's it.. Stop!!!

No more!!

For now!!! ;)

[AB]

Sorry for the hijack dakka, bloody Jonathan ;)

Get back to us when the thermostat is replaced mate?

[dakka1]

hahaha all good mate. well I put in the new tstat and also pulled the water pump off to check the impeller. water pump is aok and all put back on. I bled the system and because my housing doesn't have the bleed in it I took the hose off that goes from the housing back to the radiator near the cap and bled it that way. gave it a couple of burps while heating up. so I went on a test drive air con turned on flat out and labouring every gear nothing gets a diesel hotter then the old air con and labour trick in my book. got to me old mans which is next suburb and the temp was just shy of 3/4. by the time we fluffed about looking for his thermometer and me being scared to shit slowly undoing the radiator cap to release the pressure we mangaged to get a reading of 80 degress at half way on the gauge. drove home doing the same thing and now the needle wont go over half. overflow bottle is as full as it gets so will check in the morning to see if its sucked any back in and go for round 2.

anyone know what 3/4 temp should be in degrees on this unreliable gauges?
also I saw a few comments back old mates car sits on 3/4 when its fully loaded. that's what mine was doing when I had the camper on it wouldn't come of 3/4 for quids

[the evil twin]

I'm not sure why people consider the factory gauge unreliable, it is my experience that they are quite good IE if the engine is in it's operating range then so is the gauge.
What they aren't is a linear scale gauge so it is difficult to assign a temperature to a needle position.

Having said that, it may possibly be in this case that the sensor or gauge is U/S.
80 degrees at atmospheric pressure is not very hot at all.
I would be very tempted to pull the sensor out and stick it in boiling water and see what the gauge reads to see if the engine is actually overheating or the indication is false.

[MudRunnerTD]

You could also consider cutting is a second water temp gauge into your top hose. Even as a temporary thing it will give you a good idea what the factory gauge is telling you.

[liftlid]

I remember seeing a post from you about this the other day but can't remember what you said. Has it always been like that loaded up 3/4 temp?
Na this is a new thing for me did the Kimberly and 2 Simpson trips with the turbo without issue.
The only change I've made is to install a bigger snorkel and a new airbox and now I have heating issues

[jet]

They arent hot until gauge is in the red, fit a normal temp unit and youll see.
Factory gauges arent unreliable just display is not linear. Difference in temp between normal spot and the red is not much
Setup so needle remains in one place most of the time.
Good for normal use, bad for diagnosing problems

[dakka1]

ok so sorry I haven't been keeping this upto date. latest news is I fitted a temp gauge so I could see what temps I am getting and put a number to it. with aircon on and cruising around localy the car sits on 90 degrees. in my eyes that's plenty safe. but on the highway or at idle (as I don't have an a/c thermo fan) the motor runs at about 115 degrees.

now I decided to use as hubk as I cherish my fingers to check the viscous hub. this test is to see when the fan kicks in without a/c on. engine running use said stick to bring fan to a stop some slight resistance to hold it in place and stop it from spinning. engine temp rose to 115 and that's when I decided to pull the stick the fan spins and then it locked as I couldn't get it to stop again. this tells me the fan is fine as they wont lock up while stopped as they will just slip the fluid on the inside.

so to recap thermostat is new radiator is brand new alloy NON EBAY clutch fan is good water pump is good. im at a lose. at 100km/h its on 115 come back to 80 and it dropes to 90 with aircon off.

at 100 the fan really doesn't do much as there should be sufficient flow to cool but for some reason im not getting enough cooling. bull bar is not in the way of flow the spotties don't sit infront of the grill so got me buggered and honestly frustrated

[the evil twin]

115 degrees is really hot cobber, that is bad juju.

Radiator Cap been replaced and cooling sytem pressure tested?

[dakka1]

yep sure has

[the evil twin]

yep sure has

.... sheeeeeeit, man... no wonder your frustrated.
'fraid I am out of ideas... next step is probably an exorcism

[dakka1]

can see through the condenser clear as day to

[salmon3268]

Is your intake blocked or clogged up at all?

[bigkevlittletruck]

I know its a new thermostat but I would double check it I've had new ones play up. And I modified my scowling so the fan sucks through the whole radiator now never gets over 85 with the aircon on

[HappyCamper*]

With engine running radiator cap removed ( do this when engine is cold & warming up ) is there small bubbles or the odd big bubble ?? If so leaky head gasket , Had this on a tojo ute .

[Scorpiovee]

Check your timing too. I had the same issue with my old GQ 4.2 oiler. Adjustment is a matter of turning the injector pump one way or the the other, only very little adjustments, take it for a spin, see how it reacts with your cooling and your power too. Took me 2 hours north of Broken Hill bet got it sorted with good power output and it started easier too.

[dakka1]

went out on the weekend and found that it sat on about 95 on the highway and went to 105 up the gateway bridge. with air con on she sits on 95 at idle and as I don't have a ac thermofan I just bump the idle up to 1000 and its enough engine fan speed to hold it there. im thinking I could of had an air lock or something coz she hasn't run over the 105 unless im labouring right up a big hill.