Technical Cooling system problem

[jackwhoo]

Have you got an expansion tank higher than the radiator or a tank that is part of radiator on the side?
This is important

 

[Sabbas]

Have you got an expansion tank higher than the radiator or a tank that is part of radiator on the side?
This is important

Expasion tank is not part of radiator,yes is higher than radiator.

 

[jackwhoo]

Thank you.

Good then the coolant level is higher than bleed points.

When cold or warm(don't get burnt)
With the tank cap removed when bleed screws loose coolant should definitely come out.

 

[Sabbas]

Thank you.

Good then the coolant level is higher than bleed points.

When cold or warm(don't get burnt)
With the tank cap removed when bleed screws loose coolant should definitely come out.

Thank you a lot for the answer.I will try it again. the first time, I hadn't opened the reservoir cap.

 

[jackwhoo]

Try spray of water onto rad through bumper grill too when fan running see temp drops and fan stops

 

[Mike1alike]

One thing I noticed this morning was that the coolant level in the reservoir was between the 'min' and 'max' marks, exactly in the middle. Once the car warmed up, the coolant level rose to exactly the 'max' mark.

That is completely normal. That is what coolant does, expands volume when it is getting hot. That's why there is an expansion tank and there is space above the Max line.

I let the car run until it reached operating temperature and then turned it off. I opened the small radiator bleeder screw two to three turns, and it started releasing a few air bubbles. I closed it and then opened the heater bleeder screw; unfortunately, nothing came out from there—neither bubbles nor coolant.

Very good!
Nothing came out on heater breather because system pressure got released on the first breather and there was nothing to push air and coolant out.
Do that again like this:
- Let the car run until reaches operating temperature then turn engine off
- Open radiator bleeder screw 2-3 turns and wait until you see coolant dripping. If coolant doesn't drip, open that screw completely. Then open filler cap and add coolant until you see it coming out on opened bleed screw. When coolant comes out, put back the screw
- Open heater bleeding screw, first a little loose, then take it out completely. Put coolant in the tank until it comes out on heater's open screw. Put the screw back after coolant comes out
- Put tank cap back.
That is it. System is correctly bled, that way.
Check the level in the morning before starting the engine.

 

[Mike1alike]

Good then the coolant level is higher than bleed points.

When cold or warm(don't get burnt)
With the tank cap removed when bleed screws loose coolant should definitely come out.

It needs to be warm engine and opened thermostat.
Otherwise trapped air inside thermostat can remain there.

 

[Sabbas]

Good morning. After driving for about half an hour and once the car reached operating temperature, I turned it off. I opened the first bleed valve, but nothing came out—no bubbles, no fluid. I closed it and then opened the second one, but again, nothing came out. How is it possible that nothing came out?"

 

[Mike1alike]

There is air in and not much pressure built up on that short jurney.
Do that again and after opening the bleed valve, do open the expansion cap too. Then coolant will come out. After it does, close the valve and do the second valve.

 

[jackwhoo]

It looks like bleed 2 is higher than coolant level.

 

[Sabbas]

It looks like bleed 2 is higher than coolant level.

Good morning.Yes second bleed valve is higher than expansion tank

 

[jackwhoo]

Good morning.Yes second bleed valve is higher than expansion tank

Then you will need some pressure in expansion tank to over come gravity and get fluid out of 2nd bleed valve.

I'm not as confident that trapped air is cause of hot engine but it's worth checking.

Don't forget water spray test on radiator

 

[timmycm850]

That does sound like a thermostat problem. But you say it has 87°C stamped on its housing so that should be ok.
I would guess there is air inside the cooling system after that service and that is causing the problem. Cooling system bleed, may it be performed twice, if performed incorrectly does not get the air out of the system.
I recommend you do the bleed yourself, the right way.
Get the engine warmed, working temp then work carefully as it will be hot. Stop the engine and open the radiator breather screw. Take it off completely and with it off, top up coolant level until it comes out of the breather. Put breather screw back and do the same for heater matrix breather located on the piping. If at the end of doing that coolant level is higher than max line, do extract some out using a little hose or so.

Its a tiny bleeder screw on the other end of the radiator or on the end of a tube( i dont remember)

 

[Mike1alike]

Then you will need some pressure in expansion tank to over come gravity and get fluid out of 2nd bleed valve.

It also can be done if you find an inclined space to park on while you do it, with car's front on the higher side.

 

[Sabbas]

Good morning and have a great week.
After visiting three different repair shops, unfortunately, the issue with my car has not been resolved. As I was thinking about the changes made at the first shop, I took a look at the car's timing. Could the problem with the temperature not dropping lie here?

 

[Ralf S.]

I haven't read the entire post.. but the only time I had a similar problem (running hot and the heater being required to cool the car) the problem was a faulty water pump.

Air in the system is a red herring.. all systems have air in them all the time... but they self purge when the engine is running, so worrying about every last molecule of air is a waste of time. A radiator is huge compared to the cooling requirements of the car, so a good system will work even with quite a bit of air in it.


Ralf S.

 

[jackwhoo]

Good morning and have a great week.
After visiting three different repair shops, unfortunately, the issue with my car has not been resolved. As I was thinking about the changes made at the first shop, I took a look at the car's timing. Could the problem with the temperature not dropping lie here?View attachment 489883View attachment 489884

The angle of camera makes mark and line look like they don't align but I suspect they do align when viewed correctly. Plus would not cause heat problem.


Did you have new radiator fitted ?
Have you tried water spray?

 

[Mike1alike]

I haven't read the entire post.. but the only time I had a similar problem (running hot and the heater being required to cool the car) the problem was a faulty water pump.

That can't be the problem in this case.
This is the case:

The thermostat had 87 degrees Celsius stamped on its housing. Unfortunately, I did not test it the way you suggested. I replaced the radiator last year, along with the water pump.