TPI Tuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
Sponsored by:
Sponsored by:

Someone explain this noise. Belt tensioner

Thread Tools
 
Search this Thread
 
Old 10-08-2016, 10:51 AM
  #1  
Supreme Member

Thread Starter
iTrader: (9)
 
BOTTLEDZ28's Avatar
 
Join Date: Sep 1999
Location: Mass
Posts: 3,871
Received 24 Likes on 14 Posts
Engine: 350 TPI
Transmission: A4
Axle/Gears: 3.23
Someone explain this noise. Belt tensioner

I just did a complete top end removal and installation along with removing the SMOG equipment and I'm getting this strange noise from the belt tensioner I believe. The belt is now rerouted per the AIR pump delete directions.


Last edited by BOTTLEDZ28; 10-08-2016 at 01:22 PM.
Old 10-08-2016, 11:01 PM
  #2  
Supreme Member

 
paulo57509's Avatar
 
Join Date: Jan 2000
Location: Tracy, CA
Posts: 3,178
Received 44 Likes on 38 Posts
Car: '87 IROC
Engine: LB9
Transmission: TH700R4
Re: Someone explain this noise. Belt tensioner

Take the belt off and spin the tensioner pulley by hand. How does it feel?
Old 10-08-2016, 11:14 PM
  #3  
Supreme Member

Thread Starter
iTrader: (9)
 
BOTTLEDZ28's Avatar
 
Join Date: Sep 1999
Location: Mass
Posts: 3,871
Received 24 Likes on 14 Posts
Engine: 350 TPI
Transmission: A4
Axle/Gears: 3.23
Re: Someone explain this noise. Belt tensioner

Originally Posted by paulo57509
Take the belt off and spin the tensioner pulley by hand. How does it feel?
It feels and sounds perfect. The sound is coming from the actual tensioner. It didnt do this when the AIR pump was installed. Im wondering if the tensioner is now in a slightly different position. There is a big spring inside of it so Im thinking I can lube it up slightly and see if that helps.
Old 10-08-2016, 11:16 PM
  #4  
Supreme Member

Thread Starter
iTrader: (9)
 
BOTTLEDZ28's Avatar
 
Join Date: Sep 1999
Location: Mass
Posts: 3,871
Received 24 Likes on 14 Posts
Engine: 350 TPI
Transmission: A4
Axle/Gears: 3.23
Re: Someone explain this noise. Belt tensioner

On a different note, the A/C compressor clutch clicks on and off a lot louder now when the selector mode is moved from Off to any position . Its strange
Old 10-09-2016, 12:46 AM
  #5  
Senior Member
iTrader: (1)
 
bigal55's Avatar
 
Join Date: Dec 2012
Location: Western NY
Posts: 629
Likes: 0
Received 2 Likes on 2 Posts
Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: Someone explain this noise. Belt tensioner

OK. So, correct me if I am wrong but, that tensioner seems to be moving (or at least vibrating back and forth). Not the tensioner itself, but the pulley seems to be bouncing around. Just because a bearing "feels" ok with no pressure on it, doesn't mean it's ok. Remove the belt and check the tensioner pulley bearing for excessive play or rough feel when turning the pulley. JM2C!
Old 10-09-2016, 02:01 AM
  #6  
Supreme Member

iTrader: (9)
 
84 1LE's Avatar
 
Join Date: Nov 2002
Location: Oyth
Posts: 6,181
Received 316 Likes on 259 Posts
Car: 89RS vert
Engine: Erod
Transmission: 4L65e
Axle/Gears: BW, 3.27
Re: Someone explain this noise. Belt tensioner

Have you tried a shorter belt? Guessing there is not enough tension after removing the air pump.
Old 10-09-2016, 10:46 AM
  #7  
Supreme Member

Thread Starter
iTrader: (9)
 
BOTTLEDZ28's Avatar
 
Join Date: Sep 1999
Location: Mass
Posts: 3,871
Received 24 Likes on 14 Posts
Engine: 350 TPI
Transmission: A4
Axle/Gears: 3.23
Re: Someone explain this noise. Belt tensioner

I used the belt that was speced out in the tech article here. I just went to see what the part number was on the belt but it's not printed on it.

Here is the pulley. There is no play in it. I will remove the pulley and check the bearing in a bit.

Old 10-09-2016, 02:29 PM
  #8  
Supreme Member

 
paulo57509's Avatar
 
Join Date: Jan 2000
Location: Tracy, CA
Posts: 3,178
Received 44 Likes on 38 Posts
Car: '87 IROC
Engine: LB9
Transmission: TH700R4
Re: Someone explain this noise. Belt tensioner

Originally Posted by BOTTLEDZ28
It feels and sounds perfect. The sound is coming from the actual tensioner. It didnt do this when the AIR pump was installed. Im wondering if the tensioner is now in a slightly different position. There is a big spring inside of it so Im thinking I can lube it up slightly and see if that helps.
If the pulley bearing is OK, this is the next place to look. Regardless of the belt specified in the tech article, you may need a shorter belt as someone else mentioned. The tensioner may not be providing enough force to keep the belt tight. The belt then sends harmonic vibes back to the tensioner assy (bouncy-bouncy).

Just from outward appearances, it appears that the belt is too long = there's not enough tension provided by the tensioner assy.

There's a pointer and a "scale" on the tensioner assy that's supposed to be a wear indicator of sorts. Is the pointer within the scale when the belt is installed?

Last edited by paulo57509; 10-09-2016 at 02:32 PM.
Old 10-09-2016, 02:41 PM
  #9  
Supreme Member

Thread Starter
iTrader: (9)
 
BOTTLEDZ28's Avatar
 
Join Date: Sep 1999
Location: Mass
Posts: 3,871
Received 24 Likes on 14 Posts
Engine: 350 TPI
Transmission: A4
Axle/Gears: 3.23
Re: Someone explain this noise. Belt tensioner

Engine off.


Old 10-09-2016, 07:27 PM
  #10  
Supreme Member

iTrader: (58)
 
Drew's Avatar
 
Join Date: Jul 1999
Location: Salina, KS
Posts: 20,309
Received 1,052 Likes on 748 Posts
Re: Someone explain this noise. Belt tensioner

GM has offered two different idler pulleys that bolt in place of the smog pump when it's deleted. Can you think of a logical reason they'd bother if simply running a different belt and routing accomplishes the same thing?
Old 10-09-2016, 09:43 PM
  #11  
Supreme Member

Thread Starter
iTrader: (9)
 
BOTTLEDZ28's Avatar
 
Join Date: Sep 1999
Location: Mass
Posts: 3,871
Received 24 Likes on 14 Posts
Engine: 350 TPI
Transmission: A4
Axle/Gears: 3.23
Re: Someone explain this noise. Belt tensioner

Originally Posted by Drew
GM has offered two different idler pulleys that bolt in place of the smog pump when it's deleted. Can you think of a logical reason they'd bother if simply running a different belt and routing accomplishes the same thing?
I totally understand where you're coming from but I've done this "mod" on 4
Different TPI engines and have never had this issue. Tomorrow, I will look for the part number for the delete pulley and bracket and order it and see what happens. Yes, technically, I should have just did that when I knew I was deleting the smog pump.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
sheltonw3
Tech / General Engine
4
12-07-2016 01:17 PM
The Phantom
Exterior Parts for Sale
3
10-19-2016 04:21 PM
xbazzarex
Engine/Drivetrain/Suspension Parts for Sale
1
10-01-2016 01:02 PM
siuol
Auto Detailing and Appearance
18
09-29-2016 09:54 PM
whyt86roc
Engine/Drivetrain/Suspension Parts for Sale
1
09-14-2016 08:59 PM



Quick Reply: Someone explain this noise. Belt tensioner



All times are GMT -5. The time now is 10:00 PM.