Cj1234
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I have no idea what is wrong. PLS SEND HELP
Help! My coolant temp heats up fast in idle or slow-moving traffic (around 210F+) then decreases when I start driving (around 170F-190)
- Thread starter Cj1234
- Start date
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Captcorvette
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Sounds like a bad clutch fan not working at low rpm.
Jgonick
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Just about to say the same thing. Check to see if your fan is working correctly.
Radiohead
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Either low fan throughput, lack of proper shroud or a bit of coolant flow restriction.
Vbb199
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Water pump or fan clutch
Does the fan turn freely when the engine is cold? Or does it have a bit of resistance.
Does the fan turn freely when the engine is cold? Or does it have a bit of resistance.
Broken85
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If the fan keeps spinning after you shut off the truck, then (as stated above) bad clutch.
75gmck25
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Check the fan and shroud with the engine off. Is the shroud in place? What type of fan?
If it’s a stock mechanical fan (no clutch), the belt should be tight and the fan should not move when you push on it. It is always coupled to engine speed.
If it has a flex fan, throw it away and find a stock metal fan.
If it has a fan clutch behind the metal fan, the fan should move when you push it (engine off), but have moderate resistance. Then start up the truck, let it run a few minutes, and shut it down. Now the cold fan clutch should have distributed the fluid and the fan should move freely when you push on it (engine off).
Start up the truck with the radiator cap off, and look down into the radiator where the heater hose connects. If you see water gushing into the radiator, the water pump is moving water and working.
If it’s a stock mechanical fan (no clutch), the belt should be tight and the fan should not move when you push on it. It is always coupled to engine speed.
If it has a flex fan, throw it away and find a stock metal fan.
If it has a fan clutch behind the metal fan, the fan should move when you push it (engine off), but have moderate resistance. Then start up the truck, let it run a few minutes, and shut it down. Now the cold fan clutch should have distributed the fluid and the fan should move freely when you push on it (engine off).
Start up the truck with the radiator cap off, and look down into the radiator where the heater hose connects. If you see water gushing into the radiator, the water pump is moving water and working.
Fitz
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Most likely a worn out fan clutch. I use the Hayden 2797 Severe Duty fan clutch on all of my trucks. The severe duty locks up sooner. And free wheels later than the standard duty, or heavy duty ones. Yes, it will make more noise. I would rather have a fan making more noise, pulling more air. Than one free wheeling and not pulling air through the radiator when it needs to be doing just that. Along with the 7 blade G.M. fan blade, or aftermarket one. Make sure to also use a fan shroud to "funnel' the incoming air across the radiator. Hope that helps. Semper Fi. OUT!!!!!
59840Surfer
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I tried the Hayden HD and my gas mileage got a big 3MPG hit beside the intense roaring.
I ultimately went to the dual electric fans and wired them up like my '05 GM trucks --- low voltage and high voltage (6V v 12V) and got my mileage back PLUS!
FTR ---> Newer GMs with dual fans, use a Series/Parallel relay system that gives 2-speeds to the fans.
If you're tricky and know how to use a pair of diodes, you can get 3-speeds!
Back to topic --- the Hayden is a lot of overkill IMO.
