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HELP! WHAT IS THIS VIBRATION UNDER THE HOOD? CRAZY!

  • Thread starter Thread starter biglg
  • Start date Start date Apr 25, 2006
B

biglg

New Member
Mar 13, 2006
64
0
0
Apr 25, 2006
#1
  • Apr 25, 2006
  • #1
Hi,
I purchased a 1989 Mustang Gt convertible 5 speed about 2 months ago. When I purchased it the owner was clueless. The car had 0 engine temperature. That was only 1 of 100 things wrong with the car. I drove it home and took it to the shop. I had a new thermostat, belts, radiator hoses, rear brakes adjusted, timing set properly, and some other thing done. At that time the mechanic said the fan clutch was locked in the on position. So I purchased a used fan clutch for $5 off ebay. While waiting for the fan clutch, the car stopped running one day. No fire! I had it towed 1 block to the mechanic who did the previous work. It turns out it was the ignition module. The fan clutch came in and I had the mechanic put the fan clutch on as well as replace the ignition module since they had the car!

While driving home the car had a terrible vibration, only above 3k RPMS. I thought the engine was going to fall out. I am not a mechanic so I called the shop they said to bring it in. They said the used fan clutch was warped and that was the vipration.

I purchased a new fan clutch and put it on. It still does the same thing. It only vibrates, shakes at higher RPM's, 3k +. I dont know what it is, but it is driving me crazy. Does anyone have any idea what this might be? Is it something lose? It seems it may be fan related, but I do not know. Is it the clutch, the fan itself, timing (was checked by mechanic and said to be fine), bolt lose on something? HELP ME PLEASE!

Secondly, I put on a K&N CAI. I dont remember what the car sounded like immediately after I put it on. But I dont remember it being loud. After the fan clutches, ignition module, and other work the car seems to be really loud. Like it is wrapping tighter than it is. 2k sounds like 5k. Is this the CAI, or is something else going on? Anyhelp would be appreciated. I dont want to take it to the shop, they already talked me into a new fan clutch, and that hasnt fixed the issue. Unless this one is bad also! I wouldnt think that is the issue on a brand new $65 fan clutch. Thanks in advance!
 

95GTV8

New Member
Jul 25, 2005
386
3
0
Washington State
Apr 25, 2006
#2
  • Apr 25, 2006
  • #2
possibly a failed balancer?
 

SPEEDYLIFSAVR

Founding Member
Sep 18, 2000
666
0
16
FL,89 LX 5.0
Apr 25, 2006
#3
  • Apr 25, 2006
  • #3
Dont take it to the shop anymore , the best thing you did is post here . one of the most joyous things about owning a mustang is learning to work on it yourself . there is a wealth of information here and on the internet as well as people who are willing to take the time and answer your questions .

now as far as your problem is concerned , you have a vibration . if it happened after the fan clutch was put on check water pump pulley , make sure all screws are tight and its not wobbling around . next look just below to the crank pulley , look at the harmonic balancer and make sure there is no wobble there , the rubber ring is famous for wearing out and causing vibration .
 
J

jerryD

Founding Member
Mar 16, 2000
1,061
0
37
Gladstone, MO
Apr 25, 2006
#4
  • Apr 25, 2006
  • #4
i was going to suggest to take the belt off of the car and see if the vibration is there or not. if there, probally will be the balancer. if its gone then it is obiously something else the the pulley system.
 
B

biglg

New Member
Mar 13, 2006
64
0
0
Apr 25, 2006
#5
  • Apr 25, 2006
  • #5
Pulley system

Thanks guys.

I have been posting with some other guys helping me out in another forum. they too think it is the harmonic balancer. I went out to my car and looked to the best of my knowledge, and while the car was only at idle. It does look like the balancer, if I was looking at the correct part (beind the lowest middle pulley), it looks to have a wobble. What could be wrong with it? Is it shot? Lose, cover lose? HOw much and where to get the corrective parts, or entire balancer. Thanks guys.
 

1988WHTGT

Member
Mar 31, 2005
270
0
17
Guyton, GA
Apr 25, 2006
#6
  • Apr 25, 2006
  • #6
I was gonna say balancer....I got a Professional Products one for mine from 5.o Resto. It was like $80 I think
 

SPEEDYLIFSAVR

Founding Member
Sep 18, 2000
666
0
16
FL,89 LX 5.0
Apr 26, 2006
#7
  • Apr 26, 2006
  • #7
it is a common part , you can get a stocker from any auto parts store .

The balancer is to circular pieces of metal with a rubber ring sandwiched in the middle to absorb vibration . the rubber ring wears out causing the balancer to wobble . its an easy replacement .

remove your serpentine belt , shroud and fan clutch assembly .

there is a nut inside the crank pulley , remove it and take the pulley off . you will need a puller to remove the balancer . you can rent one from Autozone or they are not expensive and can be bought at pretty much any auto part store .

once the balancer is removed you will see a groove in the shaft . make sure the new balancer is lined up with the groove , there is a little keyway included with the new balancer , put a little RTV on ot and place it in the groove .

the balancer can be a little tricky to get back on , you can gently tap it with a rubber hamer or use the nut to push it back on .

Good luck!

Here is a pic of the puller and balancer you will need .


 
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