1HZ overheating again, this time in Argentina!

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Hi Blade

took a look at your web site , very nice .
I saw the car , good clean and very good result for a DIY job .
i can't agree more with you , in many rural countries mechanics are just hammer and screwdriver and a bit of steel wire...
all you can do yourself is a big bonus .

today I was in Switzerland , and thought about you , ha ha ha .
on the return on highway , flat , 110 kmh ,EGT 300 .
your car must not overheat .
start from the cause , don't cure the effects !

I take the point on the fact that Toyota engine HZ1 is not that common in S.America , but neither in Canada or USA !
My strong suspect is that the tuning of your pump is not right , even if made by a denso pumpist .
once I had mine fixed by a Denso pumpist , the car was very reactive , acceleration and speed very good , too good, in a blast it went to 150 kmh .
the down side was the EGT , far too high for my use .
The pumpist was used to fix racing cars !
we had to remix the job .

the only place where there are selling and regularly using these kind of car in America are in the mines .
look for a mechanic next to the mines or that is servicing them .
maybe if you go to Toyota in Santiago ,they should give you some directions , where to find the right guy.

of course , bug mesh , whinch , altitude , poor fuel , all adds up , but to get low heat from the motor you need to start with low EGT .
For that , you need only to fix the carburation , that is through the pump -injector.

found the old post from a friend of us .
same story as yours , even worst!
finally she got the right man !
The man is Felix Duran in Salta , Argentina, he has worked with Toyota for many years and fixes toyotas for mining industries .
if you are near try him .

let me know the results !

by Renago
 
I also have no problems at 100kmh with the temperature... water keeps at 70-80Celcius... it's only at slow speeds uphills..

I checked my Diesel IP notes, I wrote that the IP guy in Vancouver told me that he set the max. diesel injection amount to 13.4 (cc?) instead of 12.2 as stated in the Toyota manual for a stock 1HZ. He said that is to make up for the Turbo extra air.
So I have little bit more fuel than a stock 1HZ...
Up to south america this was also no problem, it just started afterwards for unknown reasons.

You have any more infos on this guy in Salta? Can't find anything on google. We will return to Mendoza and Cordoba, Salta probably in a few months. I also got now an adress of a Toyota guy in Mendoza I will check out when I return. Supposed to know a lot too...

thnx A LOT for all your infos, really appreciate it!!!
 
If you have no problem at low altitude , the problem is the less air and pressure at high ground.
If you have less air , and conseguence less oxsigen you must use less fuel.
In my opinion your pump must give Less then stock specification fuel.
OR more air , but this is not possible.
Here is where the Toyota altitude compensator should be working.
How about your valve clearance ? Are they OK .

Ref Felix Duran , I do not have more info un this guy, I belive IT is a small garage working by word of mouth
 
Valve clearance I checked in Colombia, about 25'000km ago, was within spec on the higher side! I set them back home 100'000km ago and it almost didn't change when I checked in Colombia.

I have installed a boost compensator and removed the HAC. So no more altitude compensator. Not sure how an 1HD-T handles thinner air, it also only has a boost compensator right?

Ok, will check this guy in Mendoza and if I return to Salta (we were robbed there, so want to go back in a few months to check on the Police for results) will see if I find this Felix.
 
did now Mendoza-down to Chile, used all 200liters Diesel up. Was mostly paved roads, high tire pressure. Used 16.8liters/100km!!! That's 14mpg! Seems to me very high for good roads!
Also, at sea level at WOT I can't get the EGT anymore over 550-600Celcius, no matter what gear, RPM etc. Before it used to go up to 700Celcius so something changed.
I will change today or tomorrow when there is no wind the injectors. Still got a rebuilt set from Cusco with me.
 
fuel consumption for paved roads at 16,8 L / 100 km looks still high for me .
you should be getting ,at the very best 8,5 km/L , 11,7L/100 km
on flat paved road , max speed 90-100 kmh.
the slower the better.
550-600C is the absolute max that you should reach .
pls remember that aluminium MELTS at 660 C !!!!
some alloys maybe you get 50 C extra , but no so much more !!

I have experienced low performance with poor diesel fuel, have you tried with some additives ?
maybe that could help.
check out also the fuel filters ...

keep posting .

bye Renago
 
hi guys
sorry, looks like the gps made a mistake when joininh tracks. fuel consumption above is 14.6liter/100km, that is 16.2mpg or 6.85liter/km.
today i refilled after 850km drive on mostly good roads and only 20% low tire pressure and gravel: 13.9liter/100km or 17mpg or 7.2km/liter.
other hzj78 traveler just mailed me that he also gets 13-14liter/km here in chile/argentina.
changed 2 days ago then injectors again. didn't change anything. still after a 500m hill it got pretty warm at 110 oil and 85-90water.
weird is that since chile i can't get the EGT higher than 600celcius anymore. not sure if the pyro sensor is bad (over 100'000km on it!) or the extra oxygen down here at almost sea level is the reason? new injectors didn't change EGT either...
one thing i remembered is that SOMETHING DID change on my setup!!! in guatemala i moved the winch from the rear of the car to the front of the grill! it surely doesn't help at higher speed but at low speed i can't imagine that it changes that much??
i got an offer from all american imports on a radiator they offer that is a few inch longer/taller than the HZJ78! the hzj78 is already taller than mine, this one would be even taller! not sure if it will fit but it surely would cool better?

RAD LC 78 LARGER VERSUS STD 1 .JPG
 
Hi Blade .
ref consumption , I would never trust GPS in making consumption calculation .
as you know most GPS optimise the track according to the memory capacity .
this results in a difference of aprox 10 % at least , depending on road design .
use old school method , zero Km when you fill up , and mark km when you refill up .
pls note that if you use big tyres there could be a difference in the odometer against the real km made.
when I was using 255-85-16 tyres , there was a difference of minus 6,8% on the odometer .
which size of tyres do you have ?

ref cooling , if you have rechanged the injectors recently , the problem is in the pump.
your problem is not cooling , you are heating up too much .
consequently you are trying to cool down the car , but the problem is in the ecces heat you are producing ,
HZJ 78 , has already a bigger radiator then standard Toyotas .
I would spend my money in a good pumpist , rather then in a new radiator.
your EGT , say the same thing , TOO hot .
I have recently spoken with a pumpist here in Milan , and he believes you are using too much fuel against air .
the higher you go the worst it gets .
consequently the combustion of fuel s not complete , and you are waisting fuel and consequently overheating the engine .
Because part of it is not exploding but burning , this is the reason of overheating .
but all must be calibrated on a pump testing machinery .

keep cool and carry on .

bye Renago
 
My gps track is very accurate. Windows based tool with high track resolution. At least much more accurate than my odometer! ;) got 285/75r16, odometer is totally off.

The J7 and also 1HZ is completly unknown in argentina and chile! I wont find anyome with experience on this pump. It's pretty sure that they would destroy a running engine if i let them touch that 100'000km old pump! And i can't afford a new pump either!

I will have a visit from europe in 3weeks. I think i will get that radiator anyway. The crapy australian brass radiator is leaking again, would be now the 7th time i have to remove it! Time for a new one anyway, i am tired of making time records in removing and installing radiators! Then i will see if it helps.

If not, i have another visit in april that could take the injection pump back to europe. There are a few good pump specialist in germany. Then have it send with express mail back to chile where taxes hopefully wont kill me!

I am not sure that 550-600celcius pre turbo is too hot! Read now on 2 places that they measured 750celcius max on a STOCK 1HZ! And when you search for recommendations on the Internet most say 550-600celcius is a safe value for a turbo 1HZ. Where do you have the Information from that it's too hot?
 
Hi Blade

Well after 7 Times you remove your old radiator ! I would have repllaced IT long time ago !
If you are on the sea side you can Also look for a Yanmar specialist , they use the same motor base 1HZ, 1hdt.
Other wise the best bet is to send the pump back to Europe and re calibrate IT.
Ref temperature, in General the lower the better,
You can push your motor at 5-6-700 C , IT simply won't last long.
The high temperature stress will work in the metal and One day a hole OR a crack will show up.
The failure is NOT the results of 1 day hard driving , but the sum of many high temperature cycles.
In General the safe side is Below 500 C.

Bye Renago
 
Yep, sick of this radiator!
Today on 500-1500m hill water got 93 and oil 105 although i drove easy on the throttle and kept EGT at only 450celcius. Even if i keep EGT low, as soon as it goes up a hill it gets hot.

Did use the 9" pusher fan. Did help some, but not a big change. At idle it helped to cool quicker too.
 
drove now another 1000km on mostly good paved roads at 70-80kmh. Got down to 12.86liters/100km, that is 18.4mpg or 7.78km/liter. Pretty good for 3.8 tons I think?
going to order now that big Toyota HZJ78 radiator kit and then see what next steps I need to do...
 
on sea level it goes to 90-95 when going on mountains and oil 100-105, that's ok for me. Driving around town, freeway 72Celcius all the time, even with full AC and 25-30Celcius outside.
Problem is ABOVE 2000m, then it starts to get hot.
I will order the bigger Toyota radiator today. They send me the measurements and it's 5-6cm longer than the brass one I have. Then I will see how much it helps and hopefully no more leaks! Leaks probably also don't help to keep the system pressure high!
 
AT sea level Temperatures look fine .
If above 2000 mt IT start to heat up , definitive you have the pump not correctly set.
Close the fuel screw over that hight , as previously said too much fuel and too less oxsigen.
A garage working for mine is our Solution.

Enjoy your nice trip!

Bye Renago
 
... good decision about new OE radiator, although you probably meant KZJ78, not "HZJ78."
i did the same for my HZJ77 and cooling improved a lot.
 
just ordered it! 490EUR for the complete radiator kit with longer shroud, different bottom hose and deflector. I think it's fair.
Part number is supposed to be 16250-17078 but I couldn't find anything on the internet!? But it's supposed to be a lager HZJ78 radiator, not KZJ.
They wrote me:

Dimension of the radiator core (aluminium): 58 x 52 cm
Dimension of the radiator frame (plastic): 67 x 54 cm -> width is 54 cm and top tank to bottom tank is 67 cm

Will post my experience here when I get it installed in about 1 month.
thank you!
 
Part number for a radiator for the 78/79 series is 16400-17300.The other part number does not exist.

There is also the HDJ78/79 radiator which is supposed to be bigger, 16400-17360 but only sold in australia.
 
this is supposedly a longer radiator than the stock HZJ78. See picture above they send me.
Will ask again on the part number, just for reference.
As said, will write my feedback here when I get it in Argentina.
 

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