Help Temperature guage on high when AC on

[chukstel]

All in house, I have tried searching for this but I could not find it maybe I am not doing the right way for search.

please each time I put on the AC, After a while my engine temperature goes very high (close to the red) and I don't know what the problem is. if I don't use AC, the temperature remains in the middle. my mechanic advised that I should remove the thermostat which he removed and the temperature is still high when AC is on.

The AC man I called said the AC fan is not working but could not trace why. has anyone gotten this experience before & how he solved it help me.

I also want to know what is controlling the AC fan, any relay, fuse etc and if it can be connected directly using a new switch.

Thank you all.

 

[e9999]

If the A/C is working fine in the cabin and it causes the coolant temp to rise a lot, and removing the thermostat does not help (and it probably shouldn't make a big difference if it's opening fine) I would take a good look at the main radiator to make sure it's not plugged and at the main fan to make sure it's engaging fine. The A/C will add quite a bit of heat to the main radiator, that may be enough to take the system over the edge if it's marginal. Especially at the kind of ambient temps you must experience in Nigeria.
By "A/C fan not working when the A/C is on", do you mean an accessory fan at the main radiator? If that, and not working, that may also result in air flow across the radiator below specs and higher temps. If electric, I imagine it would have a temp sensor someplace in the coolant to turn it on. Maybe that sensor is bad? You could try feeding the fan directly from the battery and see if it runs.
Also, keep in mind, the A/C should stop working when the coolant temp rises too high.

 

[chukstel]

Radiator has been cleaned and washed with no dirt. I discovered the following issues
1. that when i am on hold up, the temperature gauge rises up a little below the RED line and when i leave the traffic moving on speed the temperature goes down to normal.

2. If i put on the AC, the condenser fan is not coming on and the temperature will rise up to the RED line. I have check to get the position of the Fan relay as i believe there should be on but i cannot find it. does anyone know the position of the fan relay?

 

[llfarms]

Im not a Landcruiser expert but it sure sounds like a blown head gasket. Does it do fine then the temperature spike? As mentioned earlier at the point the AC should cut out.

 

[Ganndolf]

Radiator has been cleaned and washed with no dirt. I discovered the following issues
1. that when i am on hold up, the temperature gauge rises up a little below the RED line and when i leave the traffic moving on speed the temperature goes down to normal.

2. If i put on the AC, the condenser fan is not coming on and the temperature will rise up to the RED line. I have check to get the position of the Fan relay as i believe there should be on but i cannot find it. does anyone know the position of the fan relay?

Hey, I work with alot of people in my engineering school from Lagos so I will try to help with the language gap as well as I can, I know its tough man.
Is the small fan on the front of the radiator and condenser not working? Or are you talking about the large fan on the back? I think you are talking about the small fan on the front, The button that makes the small fan on the front work is actually started by the pressure in your AC lines. Make sure the refrigerant(R-134a) in your AC system is full. Once you fill your AC system up to where it should be the fan should turn on immediately, if this still doesn't work please post back and we can trouble shoot some more(Search "100 series AC cooling fan" on the iH8mud search bar and you can find lots of ways to trouble shoot this problem, but the way i mentioned fixes it most of the time). I do not believe it is a Head gasket problem but here is a good way to check, Look at the clear plastic coolant tank outside of your radiator, is there any brown or black residue on the inside? if the tank is mostly clean then your head gasket is good.

If you need help translating instructions from English I can have my friends help, if you don't understand something let me know

 

[e9999]

If the temperature goes up at a stop but down when you move, that suggests to me a bad radiator or a poorly performing main fan, assuming that the water pump and the thermostat are good, and there is no constriction in the coolant circuit. If the rad is good after cleaning, then you may want to check the main fan clutch if it has one or the motor if electric. (This is a 100 Landcruiser you are talking about, right?)

Btw, I would be very careful -and probably not risk- driving the truck if you get close to or into the red line. That gauge is highly non-linear and when you are at the red, you are likely way high in temperature and near/into the danger zone. Driving it like that may be a pretty good way to blow a head gasket or damage your engine.

 

[ton504]

Hows your radiator fan clutch?

With the engine running, touch the fan slowly. See if you can stop it with your fingers. Start with light pressure so you won't kill your fingers lol.

 

[Bear Lake Cruiser]

I would use a rolled up newspaper instead of fingers

 

[chukstel]

I forgot to mention that my mechanic advice me to remove the thermostat and i drove the vehicle topping up water in the broken radiator till i have to park at a safe place to avoid more damage.

Bought a new radiator top and changed by radiator mech and no leak so far and i drove the car back to my location (a journey of over 400km and no problem) but on heavy traffic the vehicle temperature goes up and comes down when i move on high motion.