I HAVE A SPORT 4.0 SOHC THAT HAS A SQUEAL COMING FROM THE BELT.
2002 Ford Explorer
January, 13, 2012 AT 2:13 PM
I replaced the top idler pulley as it had some play in it. Still has the noise. When I spray lubricant on the smooth side of the belt while it is running, the noise goes away for 20 seconds or so, then returns. I'm guessing this rules out bearings and the alternator, right? I don't know what to try next. The alignment seems good. Thought about replacing the belt and the tensioner, but wanted to get some advice first.
Removing the belt completely might reveal 3 other possibilities
1) One of your pulleys does not turn freely (bearings)
2) There maybe sideways play/ wobble in a pulley (worn bearings)
3) The tensioner may not be tracking true due to wear
* Other than a belt or pulley problem, watch the A/C clutch while the motor is running. Sometimes the inner most part of the pulley (clutch) might drag with the a/c off and all "defrost" modes w/ heater are off. Basically what I mean is, if the compressor were completely the inner part should not drag or move at all. But they do at times. Could be a bad clutch.
If the noise only occurs when the A/C is on or in a heater "defrost" mode. Investigate the A/C compressor to possibly have bad bearings or getting ready to seize up
If you are able to get in there, a 3 foot or so piece of heater are garden hose may help. Shove one end in your ear, use the other like a stethoscope to pin down the noise (I have found that an earplug in your "free" ear helps too!)
WATCH OUT FOR THOSE PESKY MOVING PARTS. THEY CAN PUT A HURTIN' ON YOU ! ! !