LC 100 overheating

[Rebin Rajan]

I have a land cruiser 2006 model L6 1FZ-FE

Below are the chain of events to summarize

1. As the car was old i thought of changing the coolant. So change the coolant by removing the radiator hose and filing new coolant (bought new coolant from Toyota)
2. Same day night i got a call from by building security that there is coolant leak from my car which was parked in the basement of my apartment. Saw that the lower hose came off, it came off while the car was in the parking space.
3. Next day reconnected the hose filled the coolant drove out of the basement and towed the car to the garage
4. Changed the thermostat and reconnected the hose refilled the coolant and took my car back to my apartment parking. Just before going for sleep went to check on the car and saw the hose was about to come off again
5. Next day again towed to garage. Changed radiator, lower hose, hose clips, fan clutch. And mechanic asked me to have a check on the temperature
6. While driving through traffic noticed temp going above the mid level.
7. Took the car again to garage, did radiator Co2 test came positive. Did a head gasket change
8. Did regress testing on the car, still temp goes up sometimes while on idle
9. Changed the water pump as well after that
10. The temp shows around 108c on idle

Now not sure what more to check

Note: Apart from the radiator all parts are OEM

 

[AARONTLC]

I have a land cruiser 2006 model L6 1FZ-FE

Below are the chain of events to summarize

1. As the car was old i thought of changing the coolant. So change the coolant by removing the radiator hose and filing new coolant (bought new coolant from Toyota)
2. Same day night i got a call from by building security that there is coolant leak from my car which was parked in the basement of my apartment. Saw that the lower hose came off, it came off while the car was in the parking space.
3. Next day reconnected the hose filled the coolant drove out of the basement and towed the car to the garage
4. Changed the thermostat and reconnected the hose refilled the coolant and took my car back to my apartment parking. Just before going for sleep went to check on the car and saw the hose was about to come off again
5. Next day again towed to garage. Changed radiator, lower hose, hose clips, fan clutch. And mechanic asked me to have a check on the temperature
6. While driving through traffic noticed temp going above the mid level.
7. Took the car again to garage, did radiator Co2 test came positive. Did a head gasket change
8. Did regress testing on the car, still temp goes up sometimes while on idle
9. Changed the water pump as well after that
10. The temp shows around 108c on idle

Now not sure what more to check

Note: Apart from the radiator all parts are OEM

Overheating issues can be very frustrating. Feel for you.
I take it that you pass the CO2 test now?
OEM Parts. Radiator?
OEM Thermostat/gasket with jiggle valve in proper orientation?
You say temp goes up sometimes. Possibly still have air in the system?
Just to verify, Techstream or Scangauge shows 108c or just figuring off of dash gauge?
Are you getting good flow? Some people have found blockage (shop towel or debris) from previous repair.

Good luck! Sorry this is happening.

 

[excessive]

I didn't know the 1FZ was in these all the way up to 2006. interesting.
the older 1FZs had known problems with headgaskets. If you're sure the coolant is bled correctly and the water pump and thermostat are good, i would do a test for combustion gasses in the coolant/ radiator

 

[AARONTLC]

I didn't know the 1FZ was in these all the way up to 2006. interesting.
the older 1FZs had known problems with headgaskets. If you're sure the coolant is bled correctly and the water pump and thermostat are good, i would do a test for combustion gasses in the exhaust.

I think that is the CO2 test.

 

[Bisho]

I didn't know the 1FZ was in these all the way up to 2006. interesting.
the older 1FZs had known problems with headgaskets. If you're sure the coolant is bled correctly and the water pump and thermostat are good, i would do a test for combustion gasses in the exhaust.

I certainly hope his combustion gasses are in the exhaust !

 

[nissanh]

Was the coolant came out (before the flush) were dirty? If so, the sediments that were inside the engine block may have clogged the new radiator. Use an IR thermometer and check the temp gradient on all or most coolant tubes in the radiator top to bottom to see equal temp drop.

How about the fan clutch? belt in proper tension?
Any giant fog lights in front of the grill?
Clean the AC condenser for easy passage of air.

 

[excessive]

fixed it, i mean coolant /radiator

 

[Rebin Rajan]

Overheating issues can be very frustrating. Feel for you.
I take it that you pass the CO2 test now?
OEM Parts. Radiator?
OEM Thermostat/gasket with jiggle valve in proper orientation?
You say temp goes up sometimes. Possibly still have air in the system?
Just to verify, Techstream or Scangauge shows 108c or just figuring off of dash gauge?
Are you getting good flow? Some people have found blockage (shop towel or debris) from previous repair.

Good luck! Sorry this is happening.

CO2 test now doesn't show any sign of exhaust gas in the coolant.. Radiator was an aftermarket one rest all OEM parts. Can you please give some more insight on the jiggle valve position. All work was carried out in a car garage by mechanic. But i have ordered a coolant filling funnel and i will be personally trying out the burping method to see any air pockets. OBD2 scanner showed 108C.

 

[Rebin Rajan]

Was the coolant came out (before the flush) were dirty? If so, the sediments that were inside the engine block may have clogged the new radiator. Use an IR thermometer and check the temp gradient on all or most coolant tubes in the radiator top to bottom to see equal temp drop.

How about the fan clutch? belt in proper tension?
Any giant fog lights in front of the grill?
Clean the AC condenser for easy passage of air.

Before the radiator change the coolant was refilled completely 2 times, 1 while doing the hose change the other while doing the thermostat change. Fan clutched was changed, belt was changed few months back. No lights on the grill, the car is in full stock condition with no modification whatsoever

 

[AARONTLC]

CO2 test now doesn't show any sign of exhaust gas in the coolant.. Radiator was an aftermarket one rest all OEM parts. Can you please give some more insight on the jiggle valve position. All work was carried out in a car garage by mechanic. But i have ordered a coolant filling funnel and i will be personally trying out the burping method to see any air pockets. OBD2 scanner showed 108C.

Glad to hear about the CO2 test! You should be on the downhill side now. I can only speak for my 2001 with the 2UZ-FE for which the factory service manual shows the thermostat has to be positioned in the housing with the jiggle valve on the thermostat positioned as close to 12 o'clock as possible. If you verify the thermostat jiggle valve is correct, I am willing to bet that if you position your rig on a slight incline with the front being higher than the rear and using your coolant funnel kit, this will burp out the remaining air. Good luck!

 

[Rebin Rajan]

I didn't know the 1FZ was in these all the way up to 2006. interesting.
the older 1FZs had known problems with headgaskets. If you're sure the coolant is bled correctly and the water pump and thermostat are good, i would do a test for combustion gasses in the coolant/ radiator

Multiple test carried out after the head gasket change, but no sign of combustion gas in the coolant now.

 

[Rebin Rajan]

Glad to hear about the CO2 test! You should be on the downhill side now. I can only speak for my 2001 with the 2UZ-FE for which the factory service manual shows the thermostat has to be positioned in the housing with the jiggle valve on the thermostat positioned as close to 12 o'clock as possible. If you verify the thermostat jiggle valve is correct, I am willing to bet that if you position your rig on a slight incline with the front being higher than the rear and using your coolant funnel kit, this will burp out the remaining air. Good luck!

After watching some youtube videos got an idea on what is the jiggle valve, over the weekend i will verify the jiggle valve position and will also do burping. Will let you know the outcome

 

[MountaineerLC]

It may be worth posting this in the 80 Series section to find more knowledge about the 1FZ. Most of us 100 series owners are in the US with 2UZ powered trucks.

Good luck!