rockola1971
Full Access Member
I
I would have asked for the parts manager and asked him if his department is drug tested!
2000 Yukon-Long warm up time - partial heater core restriction possibly?
- Thread starter UmmScott
- Start date
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rockola1971
Full Access Member
Once engine is warmed up check inlet and outlet temp of heater core nipples with thermal scanner. The temps should be really close to each other. If the outlet is substantially lower then you have a plugged heater core but that doesnt explain your overall temp of engine being not right. A bad thermostat explains that.
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I just was looking under the hood and found a part number on my radiator
52487604
When i look that up online it is a genuine GM radiator. Whether its factory or Not i can not tell
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52487604
When i look that up online it is a genuine GM radiator. Whether its factory or Not i can not tell
Sent from my SM-G975U using Tapatalk
I looked up 52487604 at GM Parts Warehouse and no radiator came up. As a matter of fact it is not a number in their system. I then looked at RA and came up with two radiator numbers. AC Delco 21499 or 15193110-This number did show at the GM Parts Warehouse, with no rear a/c. Your original post said rear heat but I could not find anywhere in the thread where you talked about rear a/c. RA also showed AC Delco number 21650 for a rig with rear a/c. They have different core sizes.
When I punch in 52487604 at Amazon nothing but aftermarket rads come up.
At Amazon, 21499 does show an AC Delco rad. 15193110 shows numerous aftermarket rads and then does show the same 21499 AC Delco rad.
At Amazon 21650 shows AC Delco radiator.
52487604 appears to be a part number that is no longer available unless it is NOS somewhere or it may be a rad for either no rear a/c or with rear a/c and could be the one installed sometime before but could be wrong rad.
Clear as mud?
When I punch in 52487604 at Amazon nothing but aftermarket rads come up.
At Amazon, 21499 does show an AC Delco rad. 15193110 shows numerous aftermarket rads and then does show the same 21499 AC Delco rad.
At Amazon 21650 shows AC Delco radiator.
52487604 appears to be a part number that is no longer available unless it is NOS somewhere or it may be a rad for either no rear a/c or with rear a/c and could be the one installed sometime before but could be wrong rad.
Clear as mud?
Haha clear as mud yes.
I do have rear heat and rear AC.
Did some more testing. Got home, let the cooling system cool down slightly. Opened the hood, plugged in scan tool to check temp.
ECT reads 165F when i started the truck. Turned the rear heat off and front full hot and highest blower speed. Its roughly 40F here outside right now. I let it run for about 12 mins and in that time the coolant temp went from 165 to 170 on the scan tool.
Using an infrared thermometer (not as accurate but its what i have on me) the left heater core inlet line i had 150F. Im assuming its actually the same at 170F just due to the hose and error in the tool being used.
My outlet hose i could hold on to forever if i wanted and it read 125F to 130F.
I did actually have good nice heat from the vents. I am not sure what the acceptable temp drop is but i did notice something else.
The upper rad hose is pretty warm and the drivers side rad tank is pretty warm as well. I think my thermostat is not closing and is either sticking open partially or is just opening at the wrong temp.
Thoughts?
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I do have rear heat and rear AC.
Did some more testing. Got home, let the cooling system cool down slightly. Opened the hood, plugged in scan tool to check temp.
ECT reads 165F when i started the truck. Turned the rear heat off and front full hot and highest blower speed. Its roughly 40F here outside right now. I let it run for about 12 mins and in that time the coolant temp went from 165 to 170 on the scan tool.
Using an infrared thermometer (not as accurate but its what i have on me) the left heater core inlet line i had 150F. Im assuming its actually the same at 170F just due to the hose and error in the tool being used.
My outlet hose i could hold on to forever if i wanted and it read 125F to 130F.
I did actually have good nice heat from the vents. I am not sure what the acceptable temp drop is but i did notice something else.
The upper rad hose is pretty warm and the drivers side rad tank is pretty warm as well. I think my thermostat is not closing and is either sticking open partially or is just opening at the wrong temp.
Thoughts?
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Believe the scan tool value before you believe the dash gauge. Isn't it about time to change the thermostat with a known good one with the correct temp value, in order to rule that out?
Did some digging on the radiator.
I think Im going to dismiss that at this time. Its a 34" core and there's nothing too different between them to make a difference in my opinion.
Going to go after the stat and i will probably backflush the heater core anyhow.
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I think Im going to dismiss that at this time. Its a 34" core and there's nothing too different between them to make a difference in my opinion.
Going to go after the stat and i will probably backflush the heater core anyhow.
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I do think you have the original radiator. A search of GM Parts Direct for a 2000 Yukon 5.3L calls for radiator 22840117, which is what superseded yours.
