Pls oo so I have a lexus es 300 2003 model I got toks in 2019. Recently I noticed oil shortage especially after long distance. I took it to workshop, they went under and said crank shift oil seal is the culprit. They brought down the engine, changed the seals and now I am stuck with overheating. The temperature guage is exceeding half mark after some distance. The fan comes on at driving temperature, the thermostat is intact.

Now this mech said I should remove the thermostat and relay the fan, I said no. They should instead retrace what they did to find the culprit.

Instead of water to be entering engine, it's backing up into reservoir which is filled up then water is boiling and it's now flowing out of that reservoir because there's an opening on the cap one side while the other side runs to radiator. This will continue till radiator is out of water and temperature guage will be going above half. I don tire.

Is there anyway out of this other than relaying the fan and discarding the thermo. The radiator hose wants to explode. I feel the thermo is bad.

Gazzuz

Are you sure the thermostat is okay?
Have you tested it to see if it opens at boiling temperature?
It seems your thermostat isn’t opening and not allowing water enter the engine. Check your thermostat..and if it’s bad, replace it.

Retain stock fan connection and do proper diagnosis.

Take this tip,if you use an electric kettle to boil water at home,when the water is boiling the electric kettle will make a sound and switches off itself.This is because there is a thermostat that disconnect the connection between the electricity supply and the kettle boiling ring.If that thermostat is bad,the water will be boiling continuously until you disconnect the power supply yourself.
Also in fridges,if your at fridge at home is overheating,it will disconnect itself and turn off with the aid of a thermostat.When the compressor cool down it will start working again.That is what apply to most engine that is overheating.Your Thermostat may be bad.
There was a fast food restaurant I work.My department was in charge of cutting the chicken and store in the large cold room,Each time the cold room stopped working,the management would call the technician.Unknown to them,it was a thermostat that disconnected in other to allow the compressor cool before it restart.I knew all this but kept quiet to allow the technician to chop.
The technician would go to the back of the cold room and pretend as if he was doing repairs.Na lie.

It looks like your thermostat has gone bad. Consider changing it to see if the problem will be resolved.

clinician2x:
Pls oo so I have a lexus es 300 2003 model I got toks in 2020. Recently I noticed oil shortage especially after long distance. I took it to workshop, they went under and said crank shift oil seal is the culprit. They brought down the engine, changed the seals and now I am stuck with overheating. The temperature guage is exceeding half mark after some distance. The fan comes on at driving temperature, the thermostat is intact.

Now this mech said I should remove the thermostat and relay the fan, I said no. They should instead retrace what they did to find the culprit.

Instead of water to be entering engine, it's backing up into reservoir which is filled up then water is boiling and it's now flowing out of that reservoir because there's an opening on the cap one side while the other side runs to radiator. This will continue till radiator is out of water and temperature guage will be going above half. I don tire.

Is there anyway out of this other than relaying the fan and discarding the thermo. The radiator hose wants to explode. I feel the thermo is bad.

Gazzuz

Engine was brought down.
Fans still work
Radiator is not leaking

What to check (easy things):
1. If cooling system was bled properly
2. Radiator cap is still okay (replace, it's cheap)
3. Radiator hose straight and not kinked
4. Thermostat still opens at designated temp. You can test this with a boiling water
5. Fans spin in the right direction? Pulling air into the engine.

What to check (hard things):
1. Water pump
2. Gasket
3. Blocked catalyst.

9icetoo:



Engine was brought down.
Fans still work
Radiator is not leaking

What to check (easy things):
1. If cooling system was bled properly
2. Radiator cap is still okay (replace, it's cheap)
3. Radiator hose straight and not kinked
4. Thermostat still opens at designated temp. You can test this with a boiling water
5. Fans spin in the right direction? Pulling air into the engine.

What to check (hard things):
1. Water pump
2. Gasket
3. Blocked catalyst.

So i got an electrician to connect the fan to the relay and everything seems normal. I was telling them that I suspect they have not fixed the water pump properly but they said I should allow them to use the relay and see the outcome. They used the relay and car is cool temperature guage does not get upto half. However I do not want it like this. I took the thermostat home and put it in pot to heat it. However it behaved as I expected but I am not sure if it was opening at 82 degrees celcius because I no get thermometer. My guess is that this thermostat is opening at a higher temp hence my engine is running hot. I think if I get a new thermostat, I can get electrician to return things to factory and car will be ok.

Reason is because after removing the thermo, everything is working. Which means water pump is ok, radiators are fine, same is fans, gasket and there are no air packets.

Do u share same views?

clinician2x:



So i got an electrician to connect the fan to the relay and everything seems normal. I was telling them that I suspect they have not fixed the water pump properly but they said I should allow them to use the relay and see the outcome. They used the relay and car is cool temperature guage does not get upto half. However I do not want it like this. I took the thermostat home and put it in pot to heat it. However it behaved as I expected but I am not sure if it was opening at 82 degrees celcius because I no get thermometer. My guess is that this thermostat is opening at a higher temp hence my engine is running hot. I think if I get a new thermostat, I can get electrician to return things to factory and car will be ok.

Reason is because after removing the thermo, everything is working. Which means water pump is ok, radiators are fine, same is fans, gasket and there are no air packets.

Do u share same views?

After removing all the other variables.. what you're left with is the thermostat.. it's not opening as it should. Probably opening at 90c or more.. at that temp, your car will slowly overheat cos it's not fully open. Get the thermostat that opens at 82c or 86c.
You'll be fine after that and please revert that wiring back to factory settings.

Problem solved. I changed radiator cap and flushed my radiator. Easy fix