Harmonic balancer advice?
Thread Starter
Instructor
Joined: Jul 2010
Posts: 101
Likes: 13
From: Tampa FL
Harmonic balancer advice?
I had a power steering issue where the seal on the front failed, and the car sat for a couple months while I was working to get a new pump sent out to be rebuilt for the car from Turn One. I got the new pump installed yesterday with a new drive belt, and when the car was fired up it was great. Super quiet. After about thirty seconds, this squeaking/squealing noise started. I applied some belt dressing which made the problem even worse, but it's since tapered off to where it is now, which is exactly what it sounded like initially. I'm going to probably pull the AC belt off and check the tensioners, and install a new belt. I'm trying to ascertain if the noise is actually being cause by the harmonic balancer, which as you can see in the video is very slightly wobbling.
Anyone had any thoughts to shed on this before I pull the belts off again? Thanks in advance.
Anyone had any thoughts to shed on this before I pull the belts off again? Thanks in advance.
Last edited by carlspeed; Dec 20, 2016 at 12:50 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
1. I see VERY LITTLE balancer wobble.
2. Belt dressing on our belts can and will make thing worse.
3. Wash the belt dressing off with something like simple green degreaser.
4. Obtain a small toothbrush stainless wire brush and clean all the belt groves on all the grooved pulleys. Use some 240 grit wet and dry paper and rough up/clean the smooth pulley surfaces.
If you have NOT changed the AC Belt, I highly recommend that you do so.
Obtain a mechanics stethoscope or a LONG screwdriver and put it on each of the tensioners and see if one is emitting the noise.
Run the engine with out any belts and then with just the AC belt and see what happens.
2. Belt dressing on our belts can and will make thing worse.
3. Wash the belt dressing off with something like simple green degreaser.
4. Obtain a small toothbrush stainless wire brush and clean all the belt groves on all the grooved pulleys. Use some 240 grit wet and dry paper and rough up/clean the smooth pulley surfaces.
If you have NOT changed the AC Belt, I highly recommend that you do so.
Obtain a mechanics stethoscope or a LONG screwdriver and put it on each of the tensioners and see if one is emitting the noise.
Run the engine with out any belts and then with just the AC belt and see what happens.
Thread Starter
Instructor
Joined: Jul 2010
Posts: 101
Likes: 13
From: Tampa FL
Thanks so much Bill! This is actually what I just did! I took main belt off first, noise still there. I pulled the AC belt off and the noise was gone. I took off each of those idler pulleys and checked them for wobble. Although slightly worn, they are absolutely not at the end of their service life. The belt is pretty dry, so I'm going to run to the store and grab one. Put it on, and I should know if it's fixed or if I have an AC compressor issue. Thanks again!
Pro
Joined: Aug 2010
Posts: 593
Likes: 9
From: San Antonio Texas
CarlSpeed
Maybe I'm not looking at it from the correct angle but it appears the belt is not running on the balancer properly. It looks like the belt is half way off the pulley. Has the pulley walked out towards the front? Mine went all the way back and damaged the timing cover and oil pan. It's worth checking. Good luck.
Maybe I'm not looking at it from the correct angle but it appears the belt is not running on the balancer properly. It looks like the belt is half way off the pulley. Has the pulley walked out towards the front? Mine went all the way back and damaged the timing cover and oil pan. It's worth checking. Good luck.
Safety Car
Joined: Mar 2016
Posts: 3,534
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From: Atlantic Beach FL.
There is a bearing on the A/C clutch that can go bad. If you can get the clutch to engage in this weather you will be able to tell. It will stop squeaking when engaged. Otherwise it is a idler pulley.
If it is the A/C then you don't have to replace the whole unit, just the clutch.
If it is the A/C then you don't have to replace the whole unit, just the clutch.
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
While it is hard to tell from the video, it does appear the HB has started to walk. I do tech inspection for a number of autocross and HPDE events and that is the first think I check for in a C5/6. On a sunny day I look for daylight between the pulley and the front brace. You would be amazed at the number of owners who were unaware theirs has moved. I found out the hard way, running an HPDE at another club's event and my balancer walked at 5500 rpm and blew the belts off. Immediately let up and limped to the pits and when I opened the hood could see the thrown belts and the Hood insulation was badly torn.
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
CarlSpeed
Maybe I'm not looking at it from the correct angle but it appears the belt is not running on the balancer properly. It looks like the belt is half way off the pulley. Has the pulley walked out towards the front? Mine went all the way back and damaged the timing cover and oil pan. It's worth checking. Good luck.
Maybe I'm not looking at it from the correct angle but it appears the belt is not running on the balancer properly. It looks like the belt is half way off the pulley. Has the pulley walked out towards the front? Mine went all the way back and damaged the timing cover and oil pan. It's worth checking. Good luck.
What they are referring to is important. The Dampener has THREE separate parts. The HUB that attaches to the crank, an outer metal ring that the belt rides on and an elastomeric rubber strip that BONDS the hub to the outer ring.
That elastomeric rubber strip can become un-bonded and the outer ring can come loose and move forward (grinds against the steering rack) OR move reward and grinds into the front cover.
If your bely isn't running centered on the outer ring, it could be a very bad sign that your outer ring is separated and YES, that can make noise also.
Bill
Thread Starter
Instructor
Joined: Jul 2010
Posts: 101
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From: Tampa FL
It does look like it's got a slight imbalance. Maybe some members here can take videos of their own, and we can compare mine to them? In any event, in my case for right now, the AC belt was cracked and causing the squeaking. I got a new one and installed it last night. Runs great. Can't wait to flush the transmission, diff, and give it some revs at the next autocross!
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Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
It does look like it's got a slight imbalance. Maybe some members here can take videos of their own, and we can compare mine to them? In any event, in my case for right now, the AC belt was cracked and causing the squeaking. I got a new one and installed it last night. Runs great. Can't wait to flush the transmission, diff, and give it some revs at the next autocross!
BC
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I DO NOT want to assume anything or insult your intelligents but, have you read or have in hand the factory VERY DETAILED drain and FILL procedures. It’s NOTHING like you have ever seen or encountered before!!! The procedures are a MUST to do it correctly and pervent damage.
If you do it wrong you will destroy the trans. I highly recommend doing it 100% by the factory manual procedure!
Bill
If you do it wrong you will destroy the trans. I highly recommend doing it 100% by the factory manual procedure!
Bill
Safety Car
Joined: Dec 2010
Posts: 3,938
Likes: 498
From: Fords, NJ
With the car up on jackstands and level the proper procedure is as follows ( Taken from Service manual )
1-Add enough DEXRON III automatic transmission fluid to
bring the fluid level to the bottom of the threaded plug hole.
2- Start the engine and allow the engine to idle until the
transmission fluid temperature has reached the value
specified. 30- 50°C (86-122°F) Use Trans Temp reading on DIC
3- Depress the brake pedal and move the shift lever through the
gear ranges, pausing a few seconds in each range. Return the
shift lever to the PARK range.
The vehicle must be level with
the engine running and the shift lever in the PARK range.
4- If needed, add DEXRON III automatic transmission fluid in
increments of 0.5 L until the fluid drains from the threaded plug hole.
5- Allow fluid to finish draining out of the plug hole. Install the
plug and tighten to specified value. 30 N.m (22 lb ft)
1-Add enough DEXRON III automatic transmission fluid to
bring the fluid level to the bottom of the threaded plug hole.
2- Start the engine and allow the engine to idle until the
transmission fluid temperature has reached the value
specified. 30- 50°C (86-122°F) Use Trans Temp reading on DIC
3- Depress the brake pedal and move the shift lever through the
gear ranges, pausing a few seconds in each range. Return the
shift lever to the PARK range.
The vehicle must be level with
the engine running and the shift lever in the PARK range.
4- If needed, add DEXRON III automatic transmission fluid in
increments of 0.5 L until the fluid drains from the threaded plug hole.
5- Allow fluid to finish draining out of the plug hole. Install the
plug and tighten to specified value. 30 N.m (22 lb ft)
Last edited by SG Lou; Dec 23, 2016 at 03:33 PM.
Thread Starter
Instructor
Joined: Jul 2010
Posts: 101
Likes: 13
From: Tampa FL
I DO NOT want to assume anything or insult your intelligents but, have you read or have in hand the factory VERY DETAILED drain and FILL procedures. It’s NOTHING like you have ever seen or encountered before!!! The procedures are a MUST to do it correctly and pervent damage.
If you do it wrong you will destroy the trans. I highly recommend doing it 100% by the factory manual procedure!
Bill
If you do it wrong you will destroy the trans. I highly recommend doing it 100% by the factory manual procedure!
Bill
Edit: Is this write up for auto or manual transmissions?
Last edited by carlspeed; Dec 27, 2016 at 04:26 PM.
Thread Starter
Instructor
Joined: Jul 2010
Posts: 101
Likes: 13
From: Tampa FL
I had been reading up on it, and I haven't seen anyone posting something other then just draining it and filling it to when it's coming out of the fill hole. I have a manual transmission, is there something I'm missing?
pretty much this is the way I was going to do it. http://www.toquez06.com/tranny.html
pretty much this is the way I was going to do it. http://www.toquez06.com/tranny.html
Safety Car
Joined: Dec 2010
Posts: 3,938
Likes: 498
From: Fords, NJ
The procedure I posted is for an Auto Trans. You didn't state if you had a Manual or Auto.
The Manual is pretty much straight forward as you stated. The Auto drain / refill is involved as I posted.
Last edited by SG Lou; Dec 27, 2016 at 04:51 PM.
Safety Car
Joined: Dec 2010
Posts: 3,938
Likes: 498
From: Fords, NJ
Taken from Service manual:
RECOMMENDED FLUIDS
Manufacturer recommends Dexron-III(R) ATF.
TRANSMISSION FLUID CAPACITIES:
Corvette - 4.1 Qts. (3.9) (L)
(1) Fluid capacities listed are approximate. Always use procedure specified under CHECKING FLUID LEVELS when filling transmission
DRAINING & FILLING
1. Raise and suitably support the vehicle. Ensure vehicle is level. Clean away all dirt and debris from the
transmission fluid drain plug area.
2. Remove the drain plug. See Fig. 2 . Allow the transmission to drain. Install the transmission fluid drain
plug. Tighten the transmission fluid drain plug to specification. See TORQUE SPECIFICATIONS .
Application - Corvette 4.1 Qts (3.9) )L)
(1) Fluid capacities listed are approximate. Always use procedure specified under CHECKING FLUID
LEVELS when filling transmission.
3. Remove transmission fill plug. See CHECKING FLUID LEVELS . Fill transmission with appropriate
fluid to proper level.
4. Install the transmission fill plug (or TFT sensor) to the transmission. Tighten to specification. See
TORQUE SPECIFICATIONS . Connect TFT sensor harness connector, if necessary. Lower the vehicle.
TORQUE SPECIFICATIONS:
Drain & Fill Plugs 20 Ft. Lbs. (27)(N.m)
RECOMMENDED FLUIDS
Manufacturer recommends Dexron-III(R) ATF.
TRANSMISSION FLUID CAPACITIES:
Corvette - 4.1 Qts. (3.9) (L)
(1) Fluid capacities listed are approximate. Always use procedure specified under CHECKING FLUID LEVELS when filling transmission
DRAINING & FILLING
1. Raise and suitably support the vehicle. Ensure vehicle is level. Clean away all dirt and debris from the
transmission fluid drain plug area.
2. Remove the drain plug. See Fig. 2 . Allow the transmission to drain. Install the transmission fluid drain
plug. Tighten the transmission fluid drain plug to specification. See TORQUE SPECIFICATIONS .
Application - Corvette 4.1 Qts (3.9) )L)
(1) Fluid capacities listed are approximate. Always use procedure specified under CHECKING FLUID
LEVELS when filling transmission.
3. Remove transmission fill plug. See CHECKING FLUID LEVELS . Fill transmission with appropriate
fluid to proper level.
4. Install the transmission fill plug (or TFT sensor) to the transmission. Tighten to specification. See
TORQUE SPECIFICATIONS . Connect TFT sensor harness connector, if necessary. Lower the vehicle.
TORQUE SPECIFICATIONS:
Drain & Fill Plugs 20 Ft. Lbs. (27)(N.m)
Last edited by SG Lou; Dec 27, 2016 at 05:01 PM.
Safety Car
Joined: Dec 2010
Posts: 3,938
Likes: 498
From: Fords, NJ