Air Pump Eliminator Vibration Problem.
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Joined: Mar 2000
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From: Boston, MA
Air Pump Eliminator Vibration Problem.
Ok at 1800 RPM I can feel the gas pedal "vibrate". It is when you pass 1800 RPM in either direction that it happens. You can "kinda" mimmick it with the hood open and opening the TB with your hand, but it is easier to feel through the pedal.
I tightened up the bolt that is kind of like the "elbow" that connects the alternator bracket to the rest of the bracket. That cut down on it a little. I'm thinking I am going to go and try torqueing the pully bolt to 60 ft/lb and see if it helps.
Other than that, everything seems fine. :)
I tightened up the bolt that is kind of like the "elbow" that connects the alternator bracket to the rest of the bracket. That cut down on it a little. I'm thinking I am going to go and try torqueing the pully bolt to 60 ft/lb and see if it helps.
Other than that, everything seems fine. :)
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Re: Air Pump Eliminator Vibration Problem. (scorp508)
Strange,mine made no vibes at any speed I can notice.
Did you try running the engine briefly with the belt off to see if is related?
Or this happened as soon as you made the swap?
Did you try running the engine briefly with the belt off to see if is related?
Or this happened as soon as you made the swap?
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From: Boston, MA
Re: Air Pump Eliminator Vibration Problem. (Bill's86Coupe)
Or this happened as soon as you made the swap?
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From: Boston, MA
Re: Air Pump Eliminator Vibration Problem. (1991C4)
Okay, what is an air pump eliminator? 
Racer
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From: sometown new york
Re: Air Pump Eliminator Vibration Problem. (scorp508)
The vibration might be coming from something else. I wouldn't go torquing bolts to 60 ftlbs on aluminum heads. Did you remove the big disc? If so, that can be a source of vibration. It is a vibration damper. When I removed the disc, I had to add another braket to the AC compressor to stop vibration. When I installed the AIR pump eliminator, I did not get any new vibrations. Also, make sure the eliminator pulley is properly aligned and round. Sometimes the pulley warps.
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From: Boston, MA
Re: Air Pump Eliminator Vibration Problem. (connellyh)
The vibration might be coming from something else. I wouldn't go torquing bolts to 60 ftlbs on aluminum heads. Did you remove the big disc? If so, that can be a source of vibration. It is a vibration damper. When I removed the disc, I had to add another braket to the AC compressor to stop vibration. When I installed the AIR pump eliminator, I did not get any new vibrations. Also, make sure the eliminator pulley is properly aligned and round. Sometimes the pulley warps.
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Re: Air Pump Eliminator Vibration Problem. (scorp508)
Just something I wanted to share...when i went to the cruise in II,I saw BPP there setting up their vendor site...anyways I asked them a few questions and wanted to know if they made a bracket that replaced the short black one that bolted to the back of the air pump to the intake manifold for rigidity,to use with the eliminator kit.
For those that dont know,when you install the eliminator kit, the bracket can no longer reach the back of the pulley/brackets,making it useless just sitting there on the intake.
They said no,they didnt have that but one may be able to make one.
I was kinda suggesting the eliminator should have came with that bracket to keep it snug on there.
But they were cool about it and willing to share a few simple ideas like making one or adding spacers to make it reach or something along those lines.
Anyway,maybe you can make a bracket to bolt to the back of the brackets where the bolt goes through.It might make it more rigid.
Even though I didnt have any vibe problems,I thought there should be another bracket.
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Re: Air Pump Eliminator Vibration Problem. (Bill's86Coupe)
Mine vibrated pretty good when I first installed it. I tried a lot of things, like adding weight to the long bar, and using rubber washers, but after a couple of thousand miles the vibes went away.
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St. Jude Donor '10
Re: Air Pump Eliminator Vibration Problem. (DoubleAught)
I had my alternator rebuilt one time, as soon as I put it back on I felt vibration while driving. Had the alternator rebalanced etc.....turned out my clutch was going out. The vibes just happened to start at the same time.
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From: Boston, MA
Re: Air Pump Eliminator Vibration Problem. (SurfnSun)
Looking at it last night at the strip..... Fasguy noticed that there is some slight crookedness to how the kit is holding my alternator. The alternator looks like it's being pulled back in the direction of the brake master cylinder a tad bit.
I'm going to try reinstalling the bracket that goes from the alternator to exhaust manifold with some washers to see if that helps.
I'm going to try reinstalling the bracket that goes from the alternator to exhaust manifold with some washers to see if that helps.
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From: Boston, MA
Damnit!!!
I was just about to go out on a 2 hour drive to see a friend, and I decided to put the bracket back on.
While tightening the bracket, the case of the alternator itself SPLIT!!! Chaulk that up as "never seen it happen before". God damn I guess there was some stress on it!! So now I'm out an alternator, and no stores are open till morning. :( I wonder if they'll be on stock on a Sunday. How much you wanna bet Pep Boys where I have the lifetime warranty doesn't have em' in stock?
I was just about to go out on a 2 hour drive to see a friend, and I decided to put the bracket back on.
While tightening the bracket, the case of the alternator itself SPLIT!!! Chaulk that up as "never seen it happen before". God damn I guess there was some stress on it!! So now I'm out an alternator, and no stores are open till morning. :( I wonder if they'll be on stock on a Sunday. How much you wanna bet Pep Boys where I have the lifetime warranty doesn't have em' in stock?
Le Mans Master
Joined: Jul 2001
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From: Silicon Valley Kalifornia
Re: (scorp508)
That really zucks! Real bummer. Too bad you don't live up here in San Jose...I have an extra Alt in the garage. These kind of things usually happen to me. Oh BTW my air pump eliminator never vibrated since installed. Good luck.
[Modified by GRX, 6:49 PM 10/27/2001]
[Modified by GRX, 6:49 PM 10/27/2001]
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Re: (GRX)
Damn man, that suxs!! Never heard that one before!
Hope you get a replacement soon...maybe this was your vibration?Suppose it was already coming apart and that finally cracked it all the way? Either way,hope the new alt and bracket solve your vibe prolem.
What you can also do is paint a thin white line or use tape the size of pin stripe and put it on the pulley where you can see it and see if its spinning "out of round" while the engine is running at varying speeds if the shakes are still there after alt. repair.
Either way,hope it all goes well tomorrow.
Hope you get a replacement soon...maybe this was your vibration?Suppose it was already coming apart and that finally cracked it all the way? Either way,hope the new alt and bracket solve your vibe prolem.
What you can also do is paint a thin white line or use tape the size of pin stripe and put it on the pulley where you can see it and see if its spinning "out of round" while the engine is running at varying speeds if the shakes are still there after alt. repair.
Either way,hope it all goes well tomorrow.
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From: Boston, MA
Re: (Bill's86Coupe)
Either way,hope it all goes well tomorrow.
Alright guys, I got home Sunday at about 2:30pm, and had stopped at Pep Boys on the way home to pick up a new alternator.
I installed this one, and put 3 washers between the alternator and the exhaust bracket. This seemed to shim it correctly to keep it nice and straight without stressing/busting it. :) By 2:40 I had it installed and runnning. So she's back to normal and turning a nice and healthy 14.4volts.
Oh yeah..... the vibrations are gone also now. :) I also discovered that my flickering dash that I thought was a ground issue, was just a loose batter terminal bolt. Killed a lot of birds with one stone.
Melting Slicks
Joined: Sep 2001
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From: Bedford, IN
Re: Air Pump Eliminator Vibration Problem. (scorp508)
Scorp,
As I started reading this thread, I got a little bummed. Then I got to the split alt case and I got bummed big time, because I sold it to you. :( Then when I got to the end of the thread and saw that everything worked out for the best, I felt much better. :) I was camping last weekend, so I didn't get a chance to install my version of the kit. We have an autocross Sunday, so I hope I have some time Saturday to get it installed. Though I think I will have some time Sunday, I pre registered yesterday and ended up in the fifth heat with fifteen cars to a heat. Oh well I'm glad it worked out well for you. and thanks for tip on using washers at the alt.
As I started reading this thread, I got a little bummed. Then I got to the split alt case and I got bummed big time, because I sold it to you. :( Then when I got to the end of the thread and saw that everything worked out for the best, I felt much better. :) I was camping last weekend, so I didn't get a chance to install my version of the kit. We have an autocross Sunday, so I hope I have some time Saturday to get it installed. Though I think I will have some time Sunday, I pre registered yesterday and ended up in the fifth heat with fifteen cars to a heat. Oh well I'm glad it worked out well for you. and thanks for tip on using washers at the alt.
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From: Boston, MA
Then when I got to the end of the thread and saw that everything worked out for the best, I felt much better. :)
