The largest community of 1978-1988 General Motors G-Body cars. Chevrolet Malibu, El Camino, Monte Carlo; Oldsmobile Cutlass, 442, Hurst/Olds; Buick Regal, Century, T-Type, Grand National; Pontiac Grand Am, Grand Prix, LeMans, Bonneville; GMC Caballero
GBodyForum Supporting Vendor

Weird rattle sound like something stuck in the fan???

Articles about swapping engines and anything related, mounts, exhaust considerations etc.
84hurst
Master Mechanic
 
Posts: 105
Joined: Sun Aug 17, 2008 8:40 pm
Location: Lansing

Weird rattle sound like something stuck in the fan???

Postby 84hurst on Thu Jul 01, 2010 12:54 am

Allright im gonna try to describe this the best i can. i have a stock 84 H/O with the 307 of course, I get this weird noise kind of like a sound when something's stuck in a fan and kind of flaping back and fourth, Its always there when you start it cold, but then if you get on it when its warmed up it goes away. WTF??? It still does it in park so i can eliminate anything from the trans back. It gets louder as the engine rpm's rise, its not the smog pump as the barrings went bad so i cut the belt. The fan shroud is as clean as can be. So im lost as to what else could be spinning and making this noise? Anybody have any ideas or heard this???
1984 Hurst/Olds, 28000 miles, T-tops

othtim
G Body Guru
 
Posts: 403
Joined: Tue Mar 23, 2010 12:54 pm

Re: Weird rattle sound like something stuck in the fan???

Postby othtim on Tue Oct 26, 2010 3:34 pm

I know this is an old thread. But all of a sudden, my car is making a sound that is very similar. I was actually searching through old posts looking for some help, but I stumbled across this thread which already accurately describes the issue I am having. Sounds like the fan is doing strange things, but it appears to be fine. Help? :S
(19:01:20) beermonkey9417: so i was bored and decided to direct traffic

83hurst-olds
Royal Smart Person
 
Posts: 586
Joined: Tue Oct 19, 2010 2:24 pm
Location: near Oklahoma City, OK

Re: Weird rattle sound like something stuck in the fan???

Postby 83hurst-olds on Tue Oct 26, 2010 5:07 pm

Clutch fan maybe?

User avatar
pontiacgp
Royal Smart Person
 
Posts: 13050
Joined: Fri Mar 31, 2006 2:30 pm

Re: Weird rattle sound like something stuck in the fan???

Postby pontiacgp on Tue Oct 26, 2010 5:30 pm

fan blades loose?
Image

User avatar
Bonegrater
Greasemonkey
 
Posts: 65
Joined: Sun Nov 21, 2010 6:45 pm
Location: Richmond, VA

Re: Weird rattle sound like something stuck in the fan???

Postby Bonegrater on Thu Dec 09, 2010 5:15 pm

My car started doing this, and it is the fan hitting the top of the shroud. I don't know why, but it stops after the engine runs for a few minutes. Could this be worn out body bushings allowing the shroud to be low enough to just tick the fan blades? Does anyone know why this would happen? I would like to get it fixed as soon as possible.
88 Cutlass Supreme Classic
-F41 Suspension, Rally Gauges, SSII wheels, 52K, blue on blue, sexiest car ever made.

User avatar
RockSS
G Body Guru
 
Posts: 288
Joined: Sun Oct 24, 2010 1:51 pm
Location: Enfield Ct

Re: Weird rattle sound like something stuck in the fan???

Postby RockSS on Thu Dec 09, 2010 5:27 pm

It could be the clutch fan wornout I had a similar prob on my elky ... when the car is OFF i repeat OFFjust grab a hold of fan and try to wiggle it if it moves time to replace and yes other things can fatige...
79 El Camino sold
87 Monte SS
84 Cutlass

User avatar
Peter
Royal Smart Person
 
Posts: 1278
Joined: Wed Jun 27, 2007 10:10 pm
Location: MA

Re: Weird rattle sound like something stuck in the fan???

Postby Peter on Thu Dec 09, 2010 5:54 pm

waterpump bearing a possibility
Image
82 Cutlass Supreme
3.8 RIP 108032
Olds Rocket 350 with 200-4r
-reman .030 over to 355
viewtopic.php?f=25&t=1995 (build thread here)
88 Cutlass Classic- gutted and gone to rest
01 Bonneville SSEI

User avatar
G-Body_Vet
Royal Smart Person
 
Posts: 3113
Joined: Fri Oct 15, 2010 2:01 am
Location: Bolingbrook, IL

Re: Weird rattle sound like something stuck in the fan???

Postby G-Body_Vet on Thu Dec 09, 2010 6:02 pm

RockSS wrote:It could be the clutch fan wornout I had a similar prob on my elky ... when the car is OFF i repeat OFFjust grab a hold of fan and try to wiggle it if it moves time to replace and yes other things can fatige...


X2. Check for top to bottom and side to side play. Does it also sound like the rpm's are higher or like the engine is dragging? Those fan clutches do go bad. I've never seen one so worn that it would result in nicking the fan shroud though! It should spin freely too. If it doesn't you've managed to turn it into a factory flex fan.

User avatar
bill
Royal Smart Person
 
Posts: 2872
Joined: Fri Jul 11, 2008 1:09 pm
Location: southside va/lake gaston

Re: Weird rattle sound like something stuck in the fan???

Postby bill on Thu Dec 09, 2010 7:21 pm

G-Body_Vet wrote:
RockSS wrote:It could be the clutch fan wornout I had a similar prob on my elky ... when the car is OFF i repeat OFFjust grab a hold of fan and try to wiggle it if it moves time to replace and yes other things can fatige...


X2. Check for top to bottom and side to side play. Does it also sound like the rpm's are higher or like the engine is dragging? Those fan clutches do go bad. I've never seen one so worn that it would result in nicking the fan shroud though! It should spin freely too. If it doesn't you've managed to turn it into a factory flex fan.


These clutches are fill w/fluid or are spring actuated. They should turn, but with resistance (depending on how cold the air temp, the easier it will spin). A free spinning fan clutch at normal operating temps usually indicates a lack of fluid in the housing or in other cases, the spring inside is broken or weak.
GOT TORQUE?
Image
85' Cutlass Salon / Astro Roof / Stock 70 Olds 350 w/Edelbrock Performer Intake (2711) and 650cfm Edelbrock Carb (1406) / 200-4R / 2000 stall GN-Torque Conv. / 3.73 posi w/disc brake conversion / Ceramic Headers w/Pypes Duals.

User avatar
Bonegrater
Greasemonkey
 
Posts: 65
Joined: Sun Nov 21, 2010 6:45 pm
Location: Richmond, VA

Re: Weird rattle sound like something stuck in the fan???

Postby Bonegrater on Tue Dec 21, 2010 8:57 pm

Sorry it took a while to reply, the fan has no movement at all. None front to back and none side to side. I noticed it had stopped doing it for the last week or so. Then a friend from work rode with me to lunch, and he weighs around 290-300lbs. After he plopped in my seat I fired the car up and it started up again. After he got out it stopped, any ideas?
88 Cutlass Supreme Classic
-F41 Suspension, Rally Gauges, SSII wheels, 52K, blue on blue, sexiest car ever made.

Next

Return to Engine / Swaps etc.

Who is online

Users browsing this forum: FE3X CLONE, olds307 and 403, Plain Jane