Overheating 4.9

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Jul 26, 2010 | 11:40 AM

Chadly

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From: Illinois

Overheating 4.9

Hello all. Ive been having trouble keeping my 300 cooled off in this 105 degree week we have been having.my truck is a 92 I have questions about my fan clutch, i have read some of these trucks have more advanced fan units than im familiar with.. i also read that it should cycle and roar similar to a semi truck,, if this is corect mine is not doing this. up and down the road it does fine.. putting around a camp ground it runs warmer.. but if its 100 degrees and i try pulling a trailer it gets much hotter than it should. and when i say a trailer.. im talking a 16 foot car trailer with a garden tractor on it.. not 7000 lbs. i replaced the thermostat and the rad doesnt seem dirty. so the clutch is what im leaning toward. but im open to sugestions and your past experiences thanks all

Jul 26, 2010 | 03:24 PM

topdogcustoms

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Joined: Jun 2010

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From: Tempe,AZ

sounds like a fan clutch to me

Jul 26, 2010 | 08:37 PM

greasemanicure

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Joined: Feb 2008

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My 93 4.9 ran cool on the highway and heated up on the exit ramp. It was the fan clutch. Old fart at work said to use a wide paintbrush to see if you can stop the fan easily. Nothing to lose but fingers, I could stop it and even flip it backwards a turn or two with the engine running at idle and warmed up. The 93 model 4.9 seems to have two fan clutches, one with a 36mm nut and the other with a 40mm. The wrench to hold the nut and the one to hold the pulley would not fit at the same time. I had to take out two adjacent fan bolts before I could loosen the old clutch.

Jul 26, 2010 | 08:42 PM

Encho

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Joined: Dec 2004

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From: Caracas, Venezuela

If the fan clutch is gone i would also replace the water pump, those two are like Romeo and Juliet, they like to go together.

Jul 27, 2010 | 12:39 PM

Chadly

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From: Illinois

ok thats my next question... ive read that special tools are needed for this job.. but everything says 93 and up... do i need these wrenches for my 92?? thanks again

Jul 27, 2010 | 12:54 PM

andym

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Joined: Mar 2002

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From: Bonita Springs FL

Yes you need the fan clutch tool. Good luck getting it off, I had to use an engine hoist to break mine free.

Jul 27, 2010 | 01:58 PM

DreadyDiggs

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Joined: Dec 2009

Posts: 374

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From: Portsmouth, Va

I replaced my fan clutch on my 87 4.9L. Wasn't too difficult. Used a crescent wrench with the serpentine belt still on to break it loose. Then just like a 13mm to detach it from the fan. Didn't replace the water pump though, looked too good on the inside to replace haha.

If they are known for being a pain, I got very lucky haha.