Chirp Free and Happy

twob4s

Veteran Member
Joined
Nov 14, 2004
Location
Madison, WI
TDI
Passat, 1996, Blue
I am happy to say my 96 B4 serpentine belt chirping days are over after about seven months. My road to chirp freedom is as follows:

1. Replace the belt, spring tensioner and roller - stopped the chirping for about 1,000 miles only to return.


2. Replaced the almost new Continental with a Gates belt - no improvement, possibly worse.


3. Replace the vibration damper - success, no more chirping.
 

rdkern

Top Post Dawg
Joined
May 21, 2004
Location
Humboldt Co CA
TDI
Passat 1997 silver (sold after 11 years), Jetta 2000 atlantic blue
So the lesson is that the rest of us should start with #3
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
Mine took three or four successive morning applications of stop-squeal belt dressing. It hasn't squealed since, going on about two months. This even though the temperature has gotten much colder AND I've restored electrical load by re-activating the coolant heaters.
The spray was effective for me and far less costly than the pully replacement remedy.
 

twob4s

Veteran Member
Joined
Nov 14, 2004
Location
Madison, WI
TDI
Passat, 1996, Blue
Pully replacement was only $62 and no squeal even with temperatures in the teens and the coolant heaters plugged in. Although belt dressing may be a cheaper short run alternative, I would think the pully would be a better long-term solution.
 

twob4s

Veteran Member
Joined
Nov 14, 2004
Location
Madison, WI
TDI
Passat, 1996, Blue
Chris indicated the correct part # and place to buy. I think he actually was the first one to say the pulley fixed his chirp.

The replacement took me about 1/2 hour to do. I did it while the oil was draining during an oil change. Worked great since I had to remove the lower cover for the oil change anyway. Replacement is quite simple.

1. Pry the serpentine belt tensioner and lift the belt off of the alternator and tensioner pulley.

2. Remove the four hex bolts on the vibration damper. You might want some of Metalnerds hardened bolts to replace the factory ones. I find it much easier to just pull the pulley off with the power steering belt on rather than messing with the power steering pump to remove the tension.

3. Slide the new damper on.

4. Slide the pulley for the power steering on with the v-belt attached and install and tightend the four hex bolts.

5. Pry on the serpentine belt again and slip the serpentine belt on the alternator and tensioner pulley.
 

Andrei Rinea

Veteran Member
Joined
Jan 21, 2002
Location
Europe, Romania, Bucharest
TDI
VW Tiguan 4Motion 2.0 TDI 170HP (engine CBBB)
one question...
WHAT IS THE VIBRATION DAMPER? WHERE IS LOCATED? I SEARCHED ETKA FOR THIS PART# and can't find it...
Any more info on this part?
 

RIP TDI

Top Post Dawg
Joined
Feb 16, 2000
Location
Santa Barbara, CA
TDI
'15 GSW SE 6MT...... '01 Golf GLS 5MT.... '96 Passat Variant....
It's the serpentine belt (multi-rib) pulley that bolts between the crankshaft timing sprocket and the V-belt pulley. It incorporates a rubber-suspended damping mass which is mounted differently on the updated part. The number for the original part is 028 105 243 K.
 

Andrei Rinea

Veteran Member
Joined
Jan 21, 2002
Location
Europe, Romania, Bucharest
TDI
VW Tiguan 4Motion 2.0 TDI 170HP (engine CBBB)
Thanks! I found it.
So that little bugger was making the chirping? Was it too worn out or what? I have some kind of noise coming from the accessory belt area but only when it is very cold and only the first minute or less. Also I believe it's the alternator bearings because if I turn headlights on with high beams, fog lights and defroster and all electrical accesories the screeching increases with any more electrical load that I add. Any of you had alternator bearings gone south?
 

twob4s

Veteran Member
Joined
Nov 14, 2004
Location
Madison, WI
TDI
Passat, 1996, Blue
I think the reason the vibration damper causes the chirp is because the old design has rubber sandwiched in between the outer pulley and the inner portion of the pulley to dampen vibration. My assuption is that the rubber must cause some kind of flexing on the pulley causing sudden variances in belt tension and therfore chirping. The new pulley, is all metal on one half with the rubber in between on the other side resulting in less flex.

At colder temps the old pulley doesnt seem to handle belt loads very well whether it be from the A/C compressor or the alternator. Therefore, the chirping when cold because the alternator is under load from the coolant glow plugs.

I think the chirp might go away at higher temperatures because the heat causes the rubber between the metal to expand allowing for less flex.

Yes, worn alternator bearings or bushings might also lead to chirp, but I think getting rid of the poorly designed original vibration damper is a must.
 

AndyH

Registered Vendor , w/Business number
Joined
May 25, 2001
Location
San Antonio, TX
TDI
'97 Passat Wagon 410K RIP
I may have gotten an older style damper, so keep in mind as you read the rest...

I replaced my serp, tensioner, and damper last March after another rough San Antonio winter (yeah, I know, I know!).

I pulled the shaft for the tensioner/damper and greased the casting with synthetic NGLI2 general purpose grease (I'd recommend using an NGLI 2 or 3 heavy duty grease and will when I do this again. The heavy duty grease has molybdenum - a solid extreme pressure additive. Wheel bearing grease doesn't.)

No chirping - nice and quiet. For about 5 months. The chirping started again on cool Massachusets mornings in July.

If the damper really is the final fix, I hope the new parts last longer than the one I bought from the dealer last year.

Andy
'96 TDI Sedan, 145K miles
 

twob4s

Veteran Member
Joined
Nov 14, 2004
Location
Madison, WI
TDI
Passat, 1996, Blue
Perhaps someone could post a picture to show the difference between the old and the new style and you could determine if you have the new design?

I would but I am not sure how to post pictures on here and I would have to take the newly installed damper off to take a picture of the backside of it.
 

robertgalka

Veteran Member
Joined
Sep 13, 2004
Location
Winnipeg Canada
TDI
2015 Passat Highline
From what I remember the old one has one extra hole around the bolt holes, and the new one has four extra. Old one, five holes new, eight holes. Does that make sense?
 

RIP TDI

Top Post Dawg
Joined
Feb 16, 2000
Location
Santa Barbara, CA
TDI
'15 GSW SE 6MT...... '01 Golf GLS 5MT.... '96 Passat Variant....


Original 1Z/AHU harmonic balancer on the left, updated version on the right - Front view



Rear view

Balancing mass of the original is rubber-mounted to the outer perimeter of the hub and doubles as the multi-groove pulley.

Updated version has the pulley integral with the hub and the outer diameter of the balancing mass rubber-mounted to the inner diameter of the pulley section.
 

paramedick

TDIClub Enthusiast, Vendor
Joined
Jul 29, 2001
Location
Versailles, Kentucky
TDI
2015 Audi Q5 TDI
Chris, thanks for posting. I gotta do this in the spring. Replacing the tensioner roller did nothing for my squeak/chirp.
 

RIP TDI

Top Post Dawg
Joined
Feb 16, 2000
Location
Santa Barbara, CA
TDI
'15 GSW SE 6MT...... '01 Golf GLS 5MT.... '96 Passat Variant....
I haven't seen reports of the roller causing the chirping problem, only the tensioner spring and balancer.
 

paramedick

TDIClub Enthusiast, Vendor
Joined
Jul 29, 2001
Location
Versailles, Kentucky
TDI
2015 Audi Q5 TDI
I haven't seen reports of the roller causing the chirping problem, only the tensioner spring and balancer.
Yeah, I know this now. Someone suggested this to me just after I got my car. Said to try this before replacing the tensioner spring. Never even mentioned the balancer.


Oh, well, at least I know the roller is good.
 

99GTsc

Well-known member
Joined
Aug 3, 2001
Location
CA
TDI
2009 R8 TDI
Yet another thing to do on my B4. The list is growing, but I'll be chirp free...
 

AndyH

Registered Vendor , w/Business number
Joined
May 25, 2001
Location
San Antonio, TX
TDI
'97 Passat Wagon 410K RIP
Thanks for posting the pics, Chris. I definately got the old style. It lasted about 6 months before the chirp came back.

Andy
 

Rudy_D

New member
Joined
Nov 11, 2004
Same problem here. I disconnected the +battery cable from the alt. With no alt. load, the chirp went away. Experimented with a slightly shorter belt, thinking a little increased tension might help, plus a shorter belt might have a different springiness factor. The tensioner pully bobbles quite a bit less, the chirping is there, but not as much, and doesn't last as long. Problem NOT solved.

Because of the belt routing, a reduced belt size swings the tensioner away from the alt. pulley, and reduces % of belt contact around the alt pulley. So, this doesn't gain much. However, going down this road, a reconfigured tensioner and longer belt would improve %tage of belt contact on the alt. pulley...

An interesting temporary fix while I wait for my new style pulley:
I put the old correct sized belt back on and ran it just long enough to confirm chirping. I clipped on a rather heavy vise-grip pliers to the tensioner arm. My intention was to experiment with adding tension while it ran to see what additional tension was required. When I started the engine, no more chirp. I then unclipped the pliers, started it again, and the chirp was back. Re-clipped the pliers onto the tensioner arm and the chirp was gone. Apparently the added effective rotating mass on the tensioner arm was just enough to reduce the tensioner pulley bobbling just enough to keep if from chirping. So, I'll leave the pliers on the tensioner while I wait for the new style crank pulley to come in.

Seems like a design oversight to me. All the other engines I've ever worked on, where I've paid attention to the balancer, have the rubber mounted balancing mass isolated from the pulleys and other things (like the new style). To try to use the balancer as a pulley seems like it would mess up the effect(s) the balancer makes.

20050129: New balancer and belt from AutohausAZ installed. After several cold morning starts, seems the chirp is gone. I looked closely at the old balancer/pulley. There is some portion of the rubber between the pulley and the hub that has been squeezed out, and it looks like the pulley has some wobble due to the messed up rubber portion. This easily caused the tensioner pulley hop, which caused the chirp when the alt. load was extreme. The new balancer is a much better arrangement. It may be just in my head, but seems smoother at low speeds. For parking and driveway, etc. I usually don't use the throttle (throttle?
), and just ease the clutch a bit. It's this range of operation that now seems more smooth...FWIW.
 

RC

Top Post Dawg
Joined
Oct 13, 2000
Location
Maryland`s Eastern Shore
TDI
Two White 96 B4 Wagons
We finally replaced the older pulley one the B4 making the most noise with the upgraded one and now we`re totally chirp free. While there we replaced the belts also, it was needed. Part of the job was to installed the block heater, which works very well if fired up for about 3-4 hours. I`ve yet to give it a cold start since the wrenching so I guess I shouldn`t crow too soon.... but I`m sure the chirp is gone by the way it is behaving while warm.

Time to order another upgraded pulley and get the other B4 done.
 
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