2000 Yukon-Long warm up time - partial heater core restriction possibly?

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JonnyTahoe

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Faulty Fan Clutch very common. Been running with No Fan since Nov. started out as a radiator hose replacement project and turned into an experiment. as long as its below 20 degrees outside engine temp will never go much past the 1/4 mark at idle and yes my cooling system is all new. had it running almost an hour one time. Pics coming soon.
 

OR VietVet

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Faulty Fan Clutch very common. Been running with No Fan since Nov. started out as a radiator hose replacement project and turned into an experiment. as long as its below 20 degrees outside engine temp will never go much past the 1/4 mark at idle and yes my cooling system is all new. had it running almost an hour one time. Pics coming soon.

Even on warm days, if you are driving on the freeway at speed there is enough air flowing over the radiator, if it is in good shape and no debris in front of it, the engine should not run hot or overheat. It is even less critical when cold. In cold weather you used to see people block some of the air flow to get the engine temp higher. At idle and at low speeds, if in the warmer temps, you better have good flow across that radiator.
 
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UmmScott

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Pretty much everything on this truck is original.
Original hoses and radiator for sure. Fan clutch and water pump I believe were replaced by previous owner.

I did this job quick. Just popped off the lower rad hose and then thermostat and replaced it.
Then filled back up.
Im thinking since this truck is 20 years old, this summer I might go ahead and replace all the hoses. Dont need them busting open on me thats for sure. What u guys think?

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JonnyTahoe

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Even on warm days, if you are driving on the freeway at speed there is enough air flowing over the radiator, if it is in good shape and no debris in front of it, the engine should not run hot or overheat. It is even less critical when cold. In cold weather you used to see people block some of the air flow to get the engine temp higher. At idle and at low speeds, if in the warmer temps, you better have good flow across that radiator.
Last spring I let my Tahoe run half in the garage with the door open and it was about 40 degrees out had not put the fan back on yet (dummy) the motor went into''over heat mode'' read your owners manual it's a real mode I looked at the temp and it was almost pegged. I jumped in and took it for a cool down drive to get some air through the radiator which did cool it down but at the cost of cracking the left side radiator tank. I noticed a big difference in the engine operating temp when I installed a Brand New Radiator. I have never purchased a new radiator we use to just take them to a radiator shop and have them fixed (Harrison four core) I was surprised they are just a single core(row) and affordable.
 
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OR VietVet

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Last spring I let my Tahoe run half in the garage with the door open and it was about 40 degrees out without the fan on and didn't think nothing of it till the motor went into ''over heat'' Mode, read your owners manual it's a real mode I looked at the temp and it was almost pegged I jumped in and took it for a cool down drive to get some air through the radiator which did cool it down but at the cost of cracking the left side radiator tank. I noticed a big difference in the engine operating temp when I installed a Brand New Radiator.I have never purchased a new radiator we use to just take them to a radiator shop and have them fixed. I was surprised they are just a single core(row).


Radiators made with aluminum dissipate heat so quick that they don't need as many rows as they used to. The tank cracked typically because as the coolant drops and it is replaced with super heated steam, hotter than hot coolant, that will crack the tank or if just hot coolant the seam gives from the hot pressure.
 

OR VietVet

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Pretty much everything on this truck is original.
Original hoses and radiator for sure. Fan clutch and water pump I believe were replaced by previous owner.

I did this job quick. Just popped off the lower rad hose and then thermostat and replaced it.
Then filled back up.
Im thinking since this truck is 20 years old, this summer I might go ahead and replace all the hoses. Dont need them busting open on me thats for sure. What u guys think?

Sent from my SM-G975U using Tapatalk

Replace the hoses asap. That old are way ast when should have been done. They break down from the inside out.
 

JonnyTahoe

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Pretty much everything on this truck is original.
Original hoses and radiator for sure. Fan clutch and water pump I believe were replaced by previous owner.

I did this job quick. Just popped off the lower rad hose and then thermostat and replaced it.
Then filled back up.
Im thinking since this truck is 20 years old, this summer I might go ahead and replace all the hoses. Dont need them busting open on me thats for sure. What u guys think?

Sent from my SM-G975U using Tapatalk
I just did all my Hoses about a month ago in a cold garage with no heat. I have the same year truck you do with all original hoses ( GM numbers on them) who knew they can last 20 years +. I got my Yukon last September when it was in the 70's. I wish I would of replaced them then but that would of made to much sense.
 

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