Bad vibration when ac is on...HELP PLEASE
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Bad vibration when ac is on...HELP PLEASE
The car has been running like a dream.....I was so stoked to get her back on the road....I just did a Long Tube install.....all is good there except for not being able to get the rear brace back on the AC compressor....I did not put it back on as I could not fugure out how I could make it work.....But I did test it all out in the drive way...AC working fine and all is good.....until I had to drive home in hte rain this week and had it on and it was fine until you put your foot in it and holy crap I thought it was going to come threw the hood or something....plus I could hear a hum kinda sound when it was on.....I figured that was not a big deal so I went on until I hit the expressway and it was fine til you have your foot in it, but when cruzing...its not that bad....Well I have not drove it since and will be needing your help to figure it out and get it fixed over the weekend....I am thinking about getting rid of it alltogether....So stop me from doing this....I have spent way to much money and time getting this car to look the way I want it and will never be able to get it back....Sorry guys just a little venting....
Thanks in advance... :banghead:
Thanks in advance... :banghead:
Pro
Joined: Oct 2002
Posts: 586
Likes: 0
From: Schmuckville SA
Re: Bad vibration when ac is on...HELP PLEASE (apollo30346)
Isn't there a way to get the rear support on?
And what about the long bolt just under the pulley?
I believe it's a 1/2 inch bolt. Check to make sure
it's there. Sounds like the compressor is loose as heck.
HTH
And what about the long bolt just under the pulley?
I believe it's a 1/2 inch bolt. Check to make sure
it's there. Sounds like the compressor is loose as heck.
HTH
Melting Slicks
Joined: Jun 2002
Posts: 2,168
Likes: 16
From: Phoenix AZ
Re: Bad vibration when ac is on...HELP PLEASE (britvette)
You neede to get that rear support on somehow.
Even if you have to fabricate something that comes off a bolt on the heads or headers you need the support to eliminate the vibration. If you look closely at early L98's and late L98's you will see that GM added on all kinds of brackets to the accessory drive components to reduce these vibrations.
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Bad vibration when ac is on...HELP PLEASE (vetracer)
Thanks guys....I agree I need to get it on somehow, but I have not figured out how the heck I can do it......I have checked all the bolts and they are there and tight.....it drives perfect without the AC on, and when it's just sitting there with it on in the driveway....but that way there is no load on it like when driving.....I know someone out there with long tubes on there L-98 had to have run into this....My car is a 1988 if that helps....and thanks guys....I don't want to do something I will regret....like getting rid of it....cuz I'm fed up....
Pro
Joined: Sep 2003
Posts: 670
Likes: 1
From: charlotte nc
Re: Bad vibration when ac is on...HELP PLEASE (apollo30346)
I had a similar problem when my AC was replaced. Mechanic left the rear brace off the ac compressor bolt but left it on the exhaust manifold bolt.. The only way I saw to fix it was to use my 4 cut off tool and grind a slot so that the bracket would fit under the large bolt. I would have had to break into the AC line to put it back otherwise. My Point is that with out that rear brace, it vibrated badly when the AC was on. BTW mine is an 86 . It has a tubular brace from the front exhaust manifold brace to the large bolt on the rear of the compressor. You should be able to modify it somehow. :cheers:
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Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Bad vibration when ac is on...HELP PLEASE (dwestsr)
I am going out there now to see if I can figure out how I can get it to work....If I can't I might rip out the whole system and as I was to change out to all new parts anyways.....But I would like to still have my AC now....it's not like I get a break from the heat down here where I live....
Thanks guys for the help....I will check for cracks too while I am in there....
Thanks guys for the help....I will check for cracks too while I am in there....
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Bad vibration when ac is on...HELP PLEASE (apollo30346)
Well, I was able to get the brace back on using one of the original bolts that the brace connected to.......I really don't see any difference, but it does feel better....I took it for a test ride and I still feel it, but maybe the car just feels different with the AC on after longtubes......But something still is not right....any other thoughts......
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Bad vibration when ac is on...HELP PLEASE (britvette)
Never had the frisbee on it when I purchased it.....and the compressor is good to my knowledge, but how would I tell? It blows cold and works fine...I have checked the bracket and checked all the bolts and all related to it...and all is tight and looks perfect, but I know something is not quite right....I am at a loss....thats wht I was just thinking about removing it all and wait till the warmer weather hits again and put all new parts on.....I did notice that the blower speed when on hight sometimes has a mind of its own and slows down from time to time and then out of the blue picks right up....I don't think that would have anything to do with it....I wonder if I should just take it to the dealer to have a look......I just hate paying there prices....@ $100.00 to $125.00 per hour labor....I don't like that to much...I have better things to do with my money....
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: Bad vibration when ac is on...HELP PLEASE (apollo30346)
I don't know the symptoms of a bad a/c compressor clutch, but that may very well may be it.
The clutch should cycle on and off without noticing any change in the a/c output.
The clutch should cycle on and off without noticing any change in the a/c output.
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Bad vibration when ac is on...HELP PLEASE (CentralCoaster)
Central,
as far as the clutch goes, I really never notice it cycle as it turns the whole time.....But, I do keep it set at the lowest setting cuz it's hot down here....You think that could cause this issue?....I never thought about that one....I almost traded it in yesterday on a new Expedition......But After sinking around 5K in over the last 6months....I don't think so....I am not letting someone just have my car...and I did not spend all this money getting the car to look just like I want it for nothing....But then I do get a little fed up....
What if any is there a way to check to see if the clutch is bad?
as far as the clutch goes, I really never notice it cycle as it turns the whole time.....But, I do keep it set at the lowest setting cuz it's hot down here....You think that could cause this issue?....I never thought about that one....I almost traded it in yesterday on a new Expedition......But After sinking around 5K in over the last 6months....I don't think so....I am not letting someone just have my car...and I did not spend all this money getting the car to look just like I want it for nothing....But then I do get a little fed up....
What if any is there a way to check to see if the clutch is bad?
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: Bad vibration when ac is on...HELP PLEASE (apollo30346)
I'm not familiar with how the ac clutch works.
But turn the a/c on, and check under the hood. It cycles on and off with a distinct clicking noise... and should cycle no faster than every few seconds, maybe less depending on the a/c level or fan setting.
The compressor puts a big load on the motor (you can feel the difference, SOTP).. so that's got to be 20 hp or so right?
But turn the a/c on, and check under the hood. It cycles on and off with a distinct clicking noise... and should cycle no faster than every few seconds, maybe less depending on the a/c level or fan setting.
The compressor puts a big load on the motor (you can feel the difference, SOTP).. so that's got to be 20 hp or so right?
Thread Starter
Burning Brakes
Joined: Apr 2001
Posts: 992
Likes: 0
From: Atlanta GA
Re: Bad vibration when ac is on...HELP PLEASE (CentralCoaster)
Well I went out there to check to see if the clutch was out of wack, but have no idea what I would be looking for...I can grab it and move it in either direction with resistance....I do see any type of oil leaking out .......I turned it on and it just runs and never cycles off even after setting there in the driveway for a good 30 mins or so....I tried to adjust the high pressure switch a little as I did when I did the change over to 134A......But when I did that I did it at home and did not change any parts or pull a vaccum on it...and I did not have any gauges to look at...I just did it like the directions said......it works fine, but not like it should.....Can you just replace the clutch or should I just rip it all out and replace everything and start over.....I don't want to spend a ton of money and it not be fixed......I know what you mean about a big load....It's like night and day...it feels like it runs out of power at about 3500 RPMs when the AC is on....I hate that....My wifes Saturn doesn't even do that....what kind of crap is that......I wish I could just get it perfect.....
