HZJ75 still overheating, viscous fan questions!
- Thread starter Blade
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hi Guys !
I'm new in here , but I follow you since some time .
this is my first post , WOW !
ref the over heating , I had a fiend in similar condition then yours , HZ1
she had a similar /worst problem.
the solution was to fix the diesel pump , and the altitude compensator.
the car was driving fine from 0 to 2000 mt apron.
but when climbing hills and / or going in above 2000 mt the car was not performing , smoking black and heating.
the solution is to go to a mine !
yes a mine , because Toyota HZ1 are used in mines , and they can direct you to the right guy or maybe they have their own workshop in the mine .
the altitude compensator was made on a specific request of south america , due to the extremes condition of working that these cars had to withstand.
from 0 mt up to 5000 mt .
the Japanese engineers stayed 1 year in order to solve this problem.
in Europe and north america they are not able to solve properly this problem.
bye Renago
I'm new in here , but I follow you since some time .
this is my first post , WOW !
ref the over heating , I had a fiend in similar condition then yours , HZ1
she had a similar /worst problem.
the solution was to fix the diesel pump , and the altitude compensator.
the car was driving fine from 0 to 2000 mt apron.
but when climbing hills and / or going in above 2000 mt the car was not performing , smoking black and heating.
the solution is to go to a mine !
yes a mine , because Toyota HZ1 are used in mines , and they can direct you to the right guy or maybe they have their own workshop in the mine .
the altitude compensator was made on a specific request of south america , due to the extremes condition of working that these cars had to withstand.
from 0 mt up to 5000 mt .
the Japanese engineers stayed 1 year in order to solve this problem.
in Europe and north america they are not able to solve properly this problem.
bye Renago
- Thread starter
- #45
I don't have an HAC anymore (altitude compensator). They only work to about 3000m as much as I know, after that they just make things worst and you need to open it and block it somehow. From other travelers I heard the regular 1HZ performs terrible at 4000m or 5000m! But I never bothered with the HAC since I installed the Turbo and put a boost compensator instead of the HAC for this trip to south america!
Ok, I am in Quito at a garage... the guy is an ex race car mechanic. He is not a Diesel specialist, but he has lots of experience and good connections.
The radiator bottom tank was removed to inspect, looked all pretty clean, but he re welded the bottom and fixed that leaking spot on the bottom tank I had. He still rodded the radiator to be sure.
The mechanic said not to bother with that heavy duty radiator, it should perform very well with my car...
We washed it outside, there was still some mud and dirt in there!
Coolant was tested and it's little bit alkaline, so the head should be fine, although I have an oil leak since 100'000km on the rear of the head, probably from the camshaft oiling passage. That's why I wanted to have the coolant also tested. (was hard to find this PH paper here!)
I installed a new Toyota water pump. The old one was still ok, but the bearing was showing a little bit of play. It's just too much work to redo this anytime soon so I replaced it.
The bottom hose is very soft, since we couldn't get a good fitment we installed a coil inside to help against collapsing, although I don't think this was the problem. But just to be sure. I will order a new one in Europe.
Timing belt is new now (old one was 110'000km old) and new idler & spring. The old one had some rust spots, but looked otherwise fine.
Thermostat looked used but opened at around 75-80Celcius and at 85Celcius (the water would already boil here in Quito!) I measured 10mm opening, so it's within Toyota specs!
NOW, the injectors! We removed them and they were FULL of carbon! So bad, that I hardly could remove the brass washers! We sent them to test and the guy said they are totally shot!
They got only 70'000km on them since they were rebuild in Vancouver, Canada. The mechanic said the Diesel in this countries is terrible plus the Turbo pressure surely won't be nice on the injectors. Not sure about that. Is that normal after 70'000km? I installed now spare rebuilt ones I had still from Canada.
I just checked also the injection timing. 1.08mm! Specified is 1.03-1.09mm, so I am at the max end as the Diesel guy in Vancouver told me to set it! We set it 70'000km ago in Vancouver at 1.09mm, so it just changed 0.01mm, I guess that's good.
I hope this was the reason, the very bad injectors surely generated extra heat, the little bit dirty radiator and who knows what else...
Let's see tomorrow, will do some test drives tomorrow!
Ok, I am in Quito at a garage... the guy is an ex race car mechanic. He is not a Diesel specialist, but he has lots of experience and good connections.
The radiator bottom tank was removed to inspect, looked all pretty clean, but he re welded the bottom and fixed that leaking spot on the bottom tank I had. He still rodded the radiator to be sure.
The mechanic said not to bother with that heavy duty radiator, it should perform very well with my car...
We washed it outside, there was still some mud and dirt in there!
Coolant was tested and it's little bit alkaline, so the head should be fine, although I have an oil leak since 100'000km on the rear of the head, probably from the camshaft oiling passage. That's why I wanted to have the coolant also tested. (was hard to find this PH paper here!)
I installed a new Toyota water pump. The old one was still ok, but the bearing was showing a little bit of play. It's just too much work to redo this anytime soon so I replaced it.
The bottom hose is very soft, since we couldn't get a good fitment we installed a coil inside to help against collapsing, although I don't think this was the problem. But just to be sure. I will order a new one in Europe.
Timing belt is new now (old one was 110'000km old) and new idler & spring. The old one had some rust spots, but looked otherwise fine.
Thermostat looked used but opened at around 75-80Celcius and at 85Celcius (the water would already boil here in Quito!) I measured 10mm opening, so it's within Toyota specs!
NOW, the injectors! We removed them and they were FULL of carbon! So bad, that I hardly could remove the brass washers! We sent them to test and the guy said they are totally shot!
They got only 70'000km on them since they were rebuild in Vancouver, Canada. The mechanic said the Diesel in this countries is terrible plus the Turbo pressure surely won't be nice on the injectors. Not sure about that. Is that normal after 70'000km? I installed now spare rebuilt ones I had still from Canada.
I just checked also the injection timing. 1.08mm! Specified is 1.03-1.09mm, so I am at the max end as the Diesel guy in Vancouver told me to set it! We set it 70'000km ago in Vancouver at 1.09mm, so it just changed 0.01mm, I guess that's good.
I hope this was the reason, the very bad injectors surely generated extra heat, the little bit dirty radiator and who knows what else...
Let's see tomorrow, will do some test drives tomorrow!
Last edited:
- Thread starter
- #46
ok, did some 500-700m climbs, the water didn't go over 90Celcius, engine oil got up to 100Celcius!
I will do bigger climbs in 1.5 weeks, but so far I have a good feeling that the injectors were the reason!
I read hours and hours in different forums on this overheating issue and everybody changed everything but NOBODY ever mentioned injectors! I guess many overheating problems could be due to bad injectors?
The engine also runs very smooth now and makes less noise.
I will also observe the mileage. After I got the IP and injectors rebuilt in Canada I had 12liters/100km with fast driving (80-90kmh), in the last months I had 16liters/100km with only 60-70kmh speed. That's A HUGE increase in consumption and I guess this means a lot of extra heat right?
Anyway, will post results when I do the big climbs to 4000m and more!
My new modified temperature guage also works sweet, I love it!!!
I will do bigger climbs in 1.5 weeks, but so far I have a good feeling that the injectors were the reason!
I read hours and hours in different forums on this overheating issue and everybody changed everything but NOBODY ever mentioned injectors! I guess many overheating problems could be due to bad injectors?
The engine also runs very smooth now and makes less noise.
I will also observe the mileage. After I got the IP and injectors rebuilt in Canada I had 12liters/100km with fast driving (80-90kmh), in the last months I had 16liters/100km with only 60-70kmh speed. That's A HUGE increase in consumption and I guess this means a lot of extra heat right?
Anyway, will post results when I do the big climbs to 4000m and more!
My new modified temperature guage also works sweet, I love it!!!
Glad to hear good news !
certainly the injectors not spraying correctly have a certain weight in the equation.
ref L/km , pls consider that also the centan N or diesel quality has a drastic effect on consumption and performance.
have a nice ride
certainly the injectors not spraying correctly have a certain weight in the equation.
ref L/km , pls consider that also the centan N or diesel quality has a drastic effect on consumption and performance.
have a nice ride
In my experiencied bad diesel Quality Only reduces speed and gives higher consumption , no extra heating.
I have a hzj 78 with an HTD motor, in Mauritania I was unable to run over 90kmh,
In Morocco 110
In spain 130 ,
It was the diesel Quality .
I have a hzj 78 with an HTD motor, in Mauritania I was unable to run over 90kmh,
In Morocco 110
In spain 130 ,
It was the diesel Quality .
Sounds like you will have to drive according to temperature and smoke.
Most likely by dropping a gear and keeping decent throttle to push air and coolant till you get this sorted out.
Is she smoking black clouds or just the usual puff?
Most likely by dropping a gear and keeping decent throttle to push air and coolant till you get this sorted out.
Is she smoking black clouds or just the usual puff?
- Thread starter
- #51
no cloud.. only very few smoke at WOT... I hardly see it during the day, only see that smoke at night when I have lights from another car on the back.
As said, injection pump has perfect timing and new injection nozzles installed. Car is running much cooler now! Will do in 1 week some stronger 1000-2000m hills and see how it really performs, but I got a good feeling!
Only thing that worries me now is this metal clicking noise coming from the IP when I was turning the engine. Could be a bad timing gear bearing! Will have to find out what this noise is...
As said, injection pump has perfect timing and new injection nozzles installed. Car is running much cooler now! Will do in 1 week some stronger 1000-2000m hills and see how it really performs, but I got a good feeling!
Only thing that worries me now is this metal clicking noise coming from the IP when I was turning the engine. Could be a bad timing gear bearing! Will have to find out what this noise is...
- Thread starter
- #52
ok, did a good test a few days ago. Went from 2500m to 3700m on a very steep road. 1st gear all the time, WOT at around 500Celcius EGT (before Turbo) and 3000RPM.
The engine oil increased very slowly but reached at the end 120Celcius, water also increased slowly and went up to around 95-100Celcius. There it stabilized and didn't go up anymore.
Outside temp was around 15Celcius.
When driving regular hills the oil doesn't even go up to 100Celcius! Water always at 80-90Celcius.
That's a HUGE improvement!
So I guess for MOST people having this overheating problems they can't find a solution for: check your injectors!!!
The engine oil increased very slowly but reached at the end 120Celcius, water also increased slowly and went up to around 95-100Celcius. There it stabilized and didn't go up anymore.
Outside temp was around 15Celcius.
When driving regular hills the oil doesn't even go up to 100Celcius! Water always at 80-90Celcius.
That's a HUGE improvement!
So I guess for MOST people having this overheating problems they can't find a solution for: check your injectors!!!