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Overheating.


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#16
anjin

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You want to read at the radiator inlet  pipe, because that will give you the temperature coming past the thermostat. If thats above the factory opening temperature you need to start checking components.  The radiator fan is always my starting point as wiring can deteriorate. Then the thermostat opening and closing as it should.  Third point is the radiator  - I regard that as a consumable like oil filters and tyres.

 

If you want to scare yourself start measuring oil temperature in the sump.  I measure in Centigrade, and cool day highway running is about 82 C.  On the track I see 105 to 124 - which is take the foot of and coast around time.  Oil temperature is quite changeable with conditions and driving mode.


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#17
Sinub

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Will follow your recommendations @Anjin but I do know my fan and wires are good. As for the thermostat I do know it is working because I changed it myself and in case it is defective I am changing to a 170 degree Fahrenheit thermostat and I have tested to see if it is fully working.

Radiator as I mentioned before has been painted when the car was painted so not sure if the paint could be causing a problem.

Also I want to know people's temp around the temp sensor area and thermostat housing so I know if my engine is at the correct temperature.


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#18
GeezRX

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I suppose the extra paint on the radiator could be adversely affecting things. I do know from past experience with my rex, that the process you use when refilling the system after rebuild can directly affect things. I found that using the procedure listed below (which is from another member post here...sorry, if I could remember whos' I'd give you credit!) made all the difference in the temperature on my car...maybe it will help?

 

 

Put a short piece of clear tubing over the air bleed screw so that the tube is higher than the radiator cap. Crack open the bleeder screw until the tubing fills with fluid and watch for bubbles coming out of the tubing. Leave the bleeder screw open, as the tubing will prevent you from leaking coolant.... it will seek it's own level. Jack up the right front corner slightly to tilt the head up towards the bleeder screw. Set your heater on full heat. This will open the coolant lines to the heater core.

Remove the cap and fill the
radiator to just below the seat (where the base of the cap seals). Fill your overflow so that it is between the MIN and MAX lines on the bottle. Gently give all of the hoses a gentle squeeze to 'burp' the air out of the system. Top up as needed. Now start the engine with the cap open and the bleeder open. Continue to squeeze the hoses with the engine running until you don't see any more air burp out the radiator, or see any air bubbles coming out the air bleed. After about 60-90 seconds, close the bleeder screw and replace the cap. Allow the warm up fully or take it for a short 5 minute drive around the block until the fan kicks on at least twice. Park the car and allow it to cool fully. When completely cold to the touch, remove the cap and give the hoses a couple of squeezes to confirm the air is removed. Top up the radiator (if needed) and top up the overflow (again if needed).

Top hose hot/bottom hose cold = clogged rad.
Engine overheating/top hose cold = faulty thermostat.

 

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#19
Sinub

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Well my radiator is clogged, bottom hose is significantly colder than the top. Question is is there anyway to unclog it or just buy a new radiator?


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#20
MichaelStar

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Due to the years of scaling build up, it might be better just to buy a new one.  It will cost a bit, but the piece of mind that comes with it I think is worth it



#21
Sinub

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I was thinking that too especially since the price is not to bad. I work at pep boys so I can get a discount on a radiator but my question is if does anyone know if spectra radiators are any good? I've seen their ac condensers returned and all with leaks. I haven't seen anyone return a radiator but also haven't seen many buy one.


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#22
Sinub

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Update: just ran the car and followed GeezRX instructions on how to bleed the system. I did quite quite a bit of air out of the system. At warm up the lower hose stayed completely cold and at idle after 10 minutes. I have now run the car 10 miles and left it idling another 10 minutes, the hose is now warm. The gauge now stays half way up the gauge and 40% while the car is moving. If I turn the fan off(I have it wired up to. Switch) it goes to 65% but when on it's half way.

Things I did during this flush. Instead of just distiller water I purchased oem honda fluid and mixed it with distiller wyer for a 50/50ish mix. Also added Royal Purple Purple Ice coolant additive. Currently it's not getting hot at all and the head temp reads 202 degrees Fahrenheit. Oh and I also changed the thermo to 170 degrees Fahrenheit. Seems like it's running perfectly fine now with no heating issues


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#23
ADDvanced

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I suppose the extra paint on the radiator could be adversely affecting things. I do know from past experience with my rex, that the process you use when refilling the system after rebuild can directly affect things. I found that using the procedure listed below (which is from another member post here...sorry, if I could remember whos' I'd give you credit!) made all the difference in the temperature on my car...maybe it will help?

 

 

Put a short piece of clear tubing over the air bleed screw so that the tube is higher than the radiator cap. Crack open the bleeder screw until the tubing fills with fluid and watch for bubbles coming out of the tubing. Leave the bleeder screw open, as the tubing will prevent you from leaking coolant.... it will seek it's own level. Jack up the right front corner slightly to tilt the head up towards the bleeder screw. Set your heater on full heat. This will open the coolant lines to the heater core.

Remove the cap and fill the
radiator to just below the seat (where the base of the cap seals). Fill your overflow so that it is between the MIN and MAX lines on the bottle. Gently give all of the hoses a gentle squeeze to 'burp' the air out of the system. Top up as needed. Now start the engine with the cap open and the bleeder open. Continue to squeeze the hoses with the engine running until you don't see any more air burp out the radiator, or see any air bubbles coming out the air bleed. After about 60-90 seconds, close the bleeder screw and replace the cap. Allow the warm up fully or take it for a short 5 minute drive around the block until the fan kicks on at least twice. Park the car and allow it to cool fully. When completely cold to the touch, remove the cap and give the hoses a couple of squeezes to confirm the air is removed. Top up the radiator (if needed) and top up the overflow (again if needed).

Top hose hot/bottom hose cold = clogged rad.
Engine overheating/top hose cold = faulty thermostat.

 

This should be stickied, just sayin'.  Awesome writeup, thank you!


Edited by ADDvanced, 07 August 2021 - 05:02 PM.

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