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-Replaced the radiator
-Drained the coolant from the engine block twice.
-Replaced temperature sensor
-Replaced upper and lower radiator hoses and put on new clamps
-Tested thermostat in hot water. It opened and closed properly.
-Filled coolant with Prestone All Vehicles - 10yr/300k mi - Antifreeze+Coolant (1 Gal - Ready to Use). (Car was too old with 210,000 miles and OEM coolant too expensive.)
-Replaced radiator cap.
-Replaced reservoir cap (was cracked).
-Cleaned out reservoir hoses.
I ran the vehicle for 45 minutes. The engine did not over heat and the temp gauge was below mid-mark. After about 30 minutes the lower radiator hose was hot.
Questions:
1.) I noticed before and after I replaced the above parts that the radiator fan and the a/c condenser fan both turn on after 30 minutes without the a/c being on then they both turn off together.
2.) Then I turned on the a/c and both the radiator fan and the a/c condenser fan turn on.
Is this normal for both fans to be on at the same time as listed above?
Long answer (cooling system description taken from alldata):
Fans
How the Circuit Works
Battery voltage is supplied at all times through fuses 9 and 11 to the contacts of the A/C condenser fan relay and radiator fan relay respectively. With the ignition switch in ON (II), Battery voltage is supplied through fuse 30 to the A/C condenser fan relay coil. With the engine running, battery voltage is supplied through fuse 23 to the radiator fan relay coil.
Extremely High Coolant Temperatures
In extremely high coolant temperature conditions (Above 206 degrees F (97 degrees C)), the ECM/PCM provides ground to the coils of the A/C condenser fan relay, the radiator fan relay, and the fan control relay energizing them. Battery voltage is supplied to the A/C condenser fan motor and radiator fan motor through their respective energized relays, which activates the motors at high speed.
A/C ON
The relay control module detects that the A/C is ON when the climate control unit grounds the 12 V reference voltage sent through the A/C pressure switch. The relay control module communicates this information to the ECM/PCM through the B-CAN and F-CAN networks of the multiplex system. Upon receiving the A/C ON information, the ECM/PCM provides ground to the coil of the A/C condenser fan relay energizing it. Battery voltage is supplied to the A/C condenser fan motor and radiator fan motor in series through the energized relay, which activates the motors at low speed.
If the refrigerant pressure rises above 1470 kPa (213 psi)), the A/C pressure switch closes which signals the ECM/PCM to run the fans at high speed. The ECM/PCM provides ground to the coils of the A/C condenser fan relay, the radiator fan relay, and the fan control relay energizing them. Battery voltage is supplied to the A/C condenser fan motor and radiator fan motor through their respective energized relays, which activates the motors at high speed.
Refrigerant at Low Pressure
If the refrigerant pressure lowers below 196 kPa (28 psi), the A/C pressure switch opens removing ground from the 12 V reference voltage. The relay control module detects that the A/C pressure switch is open, and the A/C needs to be turned OFF The relay control module communicates this information to the ECM/PCM through the B-CAN and F-CAN networks of the multiplex system. Upon receiving the A/C OFF information, the ECM/PCM removes ground from the coil of the A/C condenser fan relay deenergizing it. This takes away battery voltage from the A/C condenser fan motor and radiator fan motor, which deactivates the motors.
Refrigerant at High Pressure
If the refrigerant pressure rises above 3140 kPa (455 psi), the A/C pressure switch opens removing ground from the 12 V reference voltage. The relay control module detects that the A/C pressure switch is open, and the A/C needs to be turned OFF The relay control module communicates this information to the ECM/PCM through the B-CAN and F-CAN networks of the multiplex system. Upon receiving the A/C OFF information, the ECM/PCM removes ground from the coils of the A/C condenser fan relay, the radiator fan relay, and the fan control relay deenergizing them. This takes away battery voltage from the A/C condenser fan motor and radiator fan motor, which deactivates the motors.
So although the car has ability to turn only one fan on high speed it is not used. Either both of them run on low (connected in series) or on high. My guess is that it doesn't really matter for airflow for one fan on high vs both on low, but one fan on high would make more noise than both on low, and it would cause one fan to wear out quicker than necessary. They call them "A/C Condenser fan" and "Radiator fan" but both condenser and radiator are sandwiched together, so even if you would run only one fan it would affect both condenser and radiator.
Seems like a lot of work to fix overheating. I never though anybody bothered to test the thermostat.
Seems like a lot of work to fix overheating. I never though anybody bothered to test the thermostat.
,
The upper hose radiator neck broke so I had to replace the radiator. I was a going to replace the thermostat but new OEM one costs $50, and an aftermarket Gates costs $18. I would have replaced it but from my research on this site, the OEM fails in an open position, wasn't sure about Gates and since mine was working fine, I kept it.
I have a new issue where I ran my vehicle for 1 hour and i looked underneath the car and there was a big puddle of coolant. The prior day I did the same thing for 1 hour and there was no leak. But i noticed my radiator fan was loud as it was on high and the lower radiator hose was cool. I revved the engine then checked the lower hose and it was hot. There was no leak at this time.
I can't seem to locate where the leak is coming from. I checked the water valve and the 3 hoses associated with it. At one point when was checking the water valve hoses, I looked away from the hose and looked back at the hose and there was coolant on top of the hose. I wiped it off, checked for cracks, squeezed the hose, and no leaks. So I don't know about where this all of a sudden came from?
I ran the car for another 90 minutes after i had it off for a while, and no coolant leaked. Squeezed the water valve hoses while the car was running, hoses were warm but nothing leaked. I checked under the car and no leaks.
This seems to be an intermittent leak? The puddle of coolant was underneath the driver's side of the vehicle and that's where the coolant was dripping. Coolant reservoir did not change and was still at max level. Any ideas on this leak?
Last edited by CenturionTL; 11-24-2021 at 01:50 AM.
^
Did you bleed the cooling system after all your hard work?
Even though the video is for a civic it would be similar for your TL in the absence of a bleeder valve.
Maybe it wasn't a leak. Like Zeta says, if you didn't bleed the cooling system then that "leak" could've just been the cooling system burping out the excess air. The "leak" would've come out from the reservoir.
Per the service manual instructions I bleed the following way: There was no coolant leak around the reservoir tank when i investigated where the puddle on the ground came from.
^
Under 'Coolant Replacement', step 1, on page 10-6, did you 'Start the engine. Set the heater control dial to maximum heat'...?
If not, then there still may be air trapped in the heater core / coolant system, even if you left the radiator cap loosely installed in step 10.
^
Under 'Coolant Replacement', step 1, on page 10-6, did you 'Start the engine. Set the heater control dial to maximum heat'...?
If not, then there still may be air trapped in the heater core / coolant system, even if you left the radiator cap loosely installed in step 10.
It was at maximum heat setting but not on.
I looked at the reservoir tank today and the coolant was 3/4 inch below the max line, as yesterday it was at the max line before I ran it. I filled to the max line today and took off the radiator cap and checked the coolant and it was full.
I just ran my vehicle for 90 minutes and there was no leaks.
Ok so I have a coolant leak. I just don't know exactly where it is coming from. It seems to be intermittent, but it drops a big puddle on the ground when it leaks. I did notice a coolant puddle around the atf warmer. I ran the vehicle to see if the warmer o-rings were bad or the hoses connected to them were bad. And annoyingly enough when I ran the car again to check for the source of leak it did not leak.
This is where I saw the coolant puddle underneath the atf warmer.
One of the hoses connected to the atf warmer was ripped at the end, but when i checked the vehicle again to see if this was the exact source of leak it was not wet.
So my plan now is to replace every hose the coolant runs through including the atf warmer, o-rings and the water valve assembly because, if i replace one hose and i'm wrong and its not the source of the leak, i'm wasting money on coolant. I have already spent $40 dollars on coolant. I'm going to have to spend $20 more on coolant. The problem also when locating the source of the coolant leak is when it leaks and hits a hot part on the engine it immediately dries up and i can't tell where it has dripped from, unless it gathers up in a puddle.
The parts don't seem to be too expensive only about $72 total.
So my question now is are these all the hoses that the coolant runs through?
why not just rent or buy a pressure tester and find the leak? the car doesn't have to be hot to find a leak.
also to save money buy coolant concentrate and cut it 50 / 50 with distilled water. otherwise your're paying for half a bottle of coolant and half water
So my question now is are these all the hoses that the coolant runs through?
Keep in mind that the water passage (item 8 in parts diagram below) is also in that area. That diagram has lots of possible leak points, mostly gaskets but I remember a post in the last few months about coolant hoses leading to the throttle body (e-15-10 in the diagram).
why not just rent or buy a pressure tester and find the leak? the car doesn't have to be hot to find a leak.
also to save money buy coolant concentrate and cut it 50 / 50 with distilled water. otherwise your're paying for half a bottle of coolant and half water
Thanks.
I bought a pressure tester and i bought coolant concentrate and distilled water.
The upper (Dayco) and lower hose (AcDelco) I replaced were leaking. I also used Koehler enterprises clamps.
They were bought from Amazon, I don't know why they were leaking, Perhaps the clamps were not good or the hoses? I removed them and replaced them with OEM hoses and clamps. The OEM hoses were very difficult to mount due to the hoses being very tight but the Dayco and AcDelco hoses easily slipped on.....
I just pressure tested the system and it held at approx. 16 psi.
Aftermarket hoses are usually thicker than OEM and those OEM spring clamps don't fit too well (or at all).
Also, I prefer OEM spring type clamps since they rarely leak (at least from my experience). For those universal clamps, I usually feel like I need to get them really tight for the hoses to not leak.
So the problem still persists. I narrowed down the leak to the thermostat housing, where the hose connects to it. I am going to replace the thermostat housing cover. I ran the vehicle for 1 hour and I noticed a little leak. The pressure tester didn't pick it up, perhaps the coolant needed to be hot?
Anyhow, is it possible for me to remove the lower radiator hose that connects to the thermostat housing without draining the coolant, if I keep the hose pointed upwards?
11-18-2021, 09:23 PM
