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Discussion Starter #81
What you say is technically correct but making the fans turn on will definitely cool the engine down. If it's broken it should be fixed. If he does fix everything else and the electric fans still dont work correctly then engine will still overheat with the AC on, and the AC wont be working as efficient as it should.
PROBLEM 1.

FOR ELECTRICA FAN. AC WORKS FINE. FAN NOT BROKEN. WHICH SENSOR TRIGGERS THE FAN. AS I UNDERSTAND IN MY EURO 1984 THERE IS ONLY AT AC ON. SO WHICH SENSOR TO FOCUS ON. AUX FAN NEVER START. NEVER. BUT AC WORKS FINE. STILL I WANT TO SORT IT OUT AND HAVE IT RUNNING AS IT SCHOULD.

ONLY DWG OG PICTURES PLEASE. REGARDS AUX FAN DONT START WHEN AC ON.

SORRY FOR CAPITALIXATION, COMPUTER IS FUCKED, SORRY.


Thanks for answer on above, only.
 

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Discussion Starter #82
The guy is just stubborn and wants to be spoon fed info his way . He does not want to wire the auxfan to run to see if it stops his overheating
PLEASE stay away from my posts in the future.

offending someone solves no technical problem. Thank you.

And for YOUR info i wire direct, still overheating. Thanks again.
 

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Discussion Starter #83
This is a good sign, but not proof, that the fan clutch is OK.


Increasing the RPM increases the fan speed. This points toward the fan clutch as the problem.


The fan is always driven by the viscus fluid in the clutch, sort of like a torque converter, or an old style "fluid coupling". It is sort of coasting along. When the air coming off the radiator reaches a certain temperature there is a thermostatic device that closes a passage in the clutch and forces the fluid to drive the fan more efficiently, and so at a speed closer to the actual speed of the engine. The increase in speed causes an increase in fan noise. The fact that you do not hear it leads me to believe the fan clutch is not working correctly.



What you want to do is try to flush the air passages through the radiator and condenser that the air needs to follow. Spray water through the radiator in the opposite direction that the fan pulls the air. You will likely have to loosen and move the fan shroud to do this.

If you get a lot of stuff coming out, or cannot get the water to flow freely, you should separate the condenser from the radiator so you can flush them each separately. Together they form a maze that tends to trap stuff between the two.

The fact that the engine cools when you increase the engine speed points more toward the fan clutch than anything else. If blockage were the issue, driving faster or raising engine speed would not help.

PROBLEM 2 (AND MOST IMPORTANT, OVERHEATING):

1. For those think i been fooling around for weeks. No. I have 3other cars we renovating as well at the same time, other brands, as this one been working on 3times the last month. As well as Travel 60% of the year. Thanks.

2. John you are abosolutely correct, there is a language barrier, i try my best, but dont catch all tech.english as good as you guys. Sorry for misunderstandings.

3. So i will try to flush as your advice. Any more comment ?

4. The fan clutch i can change as well. Any link to a cheap one for my type ?

You have contributed brilliant. Appriciated a lot. thank you.
 

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PROBLEM 1.

FOR ELECTRICA FAN. AC WORKS FINE. FAN NOT BROKEN. WHICH SENSOR TRIGGERS THE FAN. AS I UNDERSTAND IN MY EURO 1984 THERE IS ONLY AT AC ON. SO WHICH SENSOR TO FOCUS ON. AUX FAN NEVER START. NEVER. BUT AC WORKS FINE. STILL I WANT TO SORT IT OUT AND HAVE IT RUNNING AS IT SCHOULD.

ONLY DWG OG PICTURES PLEASE. REGARDS AUX FAN START WHEN AC ON.

Thanks for answer on above, only.
There should be 2 sensors. One is a 2 pin on your head or near thermostat, not sure on your engine. if you jump the 2 pins/wires the fan should turn on high. You can test for ohms, starts around 6 when cold and goes up to @>1000 when hot. This one is easy to replace, you may lose just a small amount of coolant when you replace - dont forget a new sealing ring.

The second is the pressure switch on the bottom of the dryer. IF your ac has enough pressure it should turn on shortly after your turn fan on AC at low speed. If your R12 is low it wont turn on. You can again jump these 2 wires and the fan should turn on low. This one is harder to replace as you must evacuate the AC system.

Please jump the 2 sensors mentioned and report back what happens with the electric fans.
 

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Discussion Starter #85
There should be 2 sensors. One is a 2 pin on your head or near thermostat, not sure on your engine. if you jump the 2 pins/wires the fan should turn on high. You can test for ohms, starts around 6 when cold and goes up to @>1000 when hot. This one is easy to replace, you may lose just a small amount of coolant when you replace - dont forget a new sealing ring.

The second is the pressure switch on the bottom of the dryer. IF your ac has enough pressure it should turn on shortly after your turn fan on AC at low speed. If your R12 is low it wont turn on. You can again jump these 2 wires and the fan should turn on low. This one is harder to replace as you must evacuate the AC system.

Please jump the 2 sensors mentioned and report back what happens with the electric fans.
Super, i understand. Will do tomorrow. Thank you much. Best
 

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4. The fan clutch i can change as well. Any link to a cheap one for my type ?

Find a good Behr one. Not a part to buy cheapest.
 

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There should be 2 sensors. One is a 2 pin on your head or near thermostat, not sure on your engine. if you jump the 2 pins/wires the fan should turn on high....The second is the pressure switch on the bottom of the dryer. IF your ac has enough pressure it should turn on shortly after your turn fan on AC at low speed.
This will probably be my last post on this thread.

As I've stated several times before, his fan does not work this way. His fan comes on only in response to refrigerant temperature. It has only one speed. If the AC is on and the temperature of the refrigerant, as measured by the temperature sensor on the receiver/dryer, exceeds 52*C the aux fan relay coil is grounded through the temperature sensor switch and the relay turns the fan on. Refer back to post 43 for the schematic.
 

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Checked today how warm the lower hose from radiator is after car has been driven warm and is idling for a couple of minutes on my 420 SEC. It is very close to ambient temperature. This is with the belt driven fan only as this car no AC. One can reach that hose by kneeling at the front of the car.
 

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Discussion Starter #90
This will probably be my last post on this thread.

As I've stated several times before, his fan does not work this way. His fan comes on only in response to refrigerant temperature. It has only one speed. If the AC is on and the temperature of the refrigerant, as measured by the temperature sensor on the receiver/dryer, exceeds 52*C the aux fan relay coil is grounded through the temperature sensor switch and the relay turns the fan on. Refer back to post 43 for the schematic.
Well recieved. trust you. Understood.

Will test it, ohm it, and take from my other car and re-test with that one.

Thanks again.
 

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Discussion Starter #91
Checked today how warm the lower hose from radiator is after car has been driven warm and is idling for a couple of minutes on my 420 SEC. It is very close to ambient temperature. This is with the belt driven fan only as this car no AC. One can reach that hose by kneeling at the front of the car.
Think mine(same one) is quite hot at same test.

So as i understand, poor circulation on my cooler. Thank you for reply.
 

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If lower hose from radiator to engine is hot coolant is circulating well but is not getting cooled in the radiator by air flow trough the radiator.
 
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