Odd Fan Noise
Thread Starter
Intermediate
Joined: Aug 2007
Posts: 33
Likes: 0
From: Sierra Vista AZ
Odd Fan Noise
Ok, this Forum has been a great help in the past, with that being said don't let me down.
About a week ago, my 76 L82 started to sound like a Jet engine around 2k RPMs regardless of gear selection. The engine is stock, from carb to oilpan, to include factory headers, the only thing changed are accessories, like P/S Pump, and Alt, as the engine is 30+ years old. No power adders.
the fan is a manual fan with clutch which attaches to the water pump(stock as far as I can tell). the source of the noise, and about a week ago it just got really, really loud, abnormally loud, is there anyone out there that can give me any indication of whats going on.
Other than the wicked loud fan noise vette runs great, if i left out anything dont hesitate to ask.
THank
JR
About a week ago, my 76 L82 started to sound like a Jet engine around 2k RPMs regardless of gear selection. The engine is stock, from carb to oilpan, to include factory headers, the only thing changed are accessories, like P/S Pump, and Alt, as the engine is 30+ years old. No power adders.
the fan is a manual fan with clutch which attaches to the water pump(stock as far as I can tell). the source of the noise, and about a week ago it just got really, really loud, abnormally loud, is there anyone out there that can give me any indication of whats going on.
Other than the wicked loud fan noise vette runs great, if i left out anything dont hesitate to ask.
THank
JR
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
I have a hunch the fan clutch has failed. With the hood up, have a friend turn the engine off. If the fan continues to spin more than three times or so after shut off, the clutch is likely to be bad.
Race Director
Joined: May 2006
Posts: 18,729
Likes: 2,581
the opposite problem can occur also, the clutch fan seizes. With the engine off try to turn the blades. If you cannt the clutch seized. Another test with the engine off try to grab two opposite blades and check for free play in the bearing, should be hardly any movement. Look for a viscous like fluid or evidence of any leakage on the fan clutch.
Last edited by MelWff; Nov 16, 2011 at 03:37 PM.
Instructor
Joined: Apr 2010
Posts: 233
Likes: 2
From: Sacramento CA
It sounds like your fan clutch "locked up". Where the the fan is spinning at the same rate as the engine itself.
With the engine off, can you move the fan blades and "spin" them?
If the fan clutch did take a poop, they are really inexpensive to replace. Around $40.
With the engine off, can you move the fan blades and "spin" them?
If the fan clutch did take a poop, they are really inexpensive to replace. Around $40.
