This whining screeching noise

This whining screeching noise


86 CJ-7 , 4.2L , 4-speed
Okay. Got my 86 CJ7, and since we've had it the thing whines and the belt squeals loud. It's like nails on a chalkboard, haha.
The belt squeal went away for the most part after new belt and a little tension adjustment; though it still does it on startup (especially if it was outside and the moisture might have gotten the belt wet?)...
This thing still makes an awful whining noise. I just have no clue what the heck is causing it.
I'm considering replacing the idler pulleys, as well as the air intake tube as it's a little beat up, but I can't imagine that would cause the noise.

Before that I would like to get some input from you guys first. Video is below!
Much appreciation. :)

86 CJ whining noise - YouTube
Last edited:
If your pulleys arent worn out(wobbly) you should be good, maybe tighten belt a little more. the whinny sound sounds to me like a vacuum leak, you might wanna put your ear in there and try to find out where it is the loudest to track it down. :chug:
Yeah, that was what my dad suggested it might be. I mean, it would make sense. Either that or something might not be tight and leaking air (maybe valve cover..)

I didn't get much help from the video, due to what sounds like a high idle on a cold engine. There is a lot of stuff that the serpentine belt has to turn and it is critical that you make its job as easy as possible. Make sure that the idler pulleys, water pump, power steering, and alternator are turning reasonably free, then just tighten up the fan belt so it doesn't squeal. I know that you can get a shorter belt if needed. If I have problems installing or removing the fan belt, removing an idler pulley helps.
Yeah, I realized the video doesn't help too much, but it was something at least. I'll pull the belt off and check the pulleys again. But damn is that thing a pain in the butt to tension!
vacuum leak
tighten all the manifold bolts
take the belt off and start it. (dont let it run for long because the water pump wont turn) if you still have the noise then its probably a vacuum leak. it sounds like a air leak to me in the video.
Aha. So it's the intake manifold gasket.pressed down on it and the whistling noise changed. Thanks for the advice everyone :)
Glad you got it figured out...from the title I thought at first you were talking about your wife. :D
I think I have one of those too. Wife that is.
Tip: next time the belt squeks in wet weather, rub bar soap on the underside of the belt. Belts squek because it doesn't slide over the pulley's when wet. Dad taught me that before I could even drive.

Jeep-CJ Donation Drive

Help support by making a donation.

Help support by making a donation.
This donation drive ends in
Top Bottom
AdBlock Detected

I get it, I'm a Jeep owner and ad-block detectors kinda stink but ads are needed on this site. This is a CJ site, all the ads are set for autos (some times others get through.) I cannot make them just for Jeeps but I try.

Please allow ads as they help keep this site running by offsetting the costs of software and server fees.
Clicking on No Thanks will temporarily disable this message.
I've Disabled AdBlock    No Thanks