Welcome to the North American Subaru Impreza Owners Club Saturday August 2, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 09-14-2011, 02:16 AM   #1
Ryguy32789
Scooby Specialist
 
Member#: 214559
Join Date: Jun 2009
Location: Chicagoland
Vehicle:
2005 WRX
OBP

Default Timing Belt Tensioner Noise Question

I had a very loud knocking noise coming from the engine last week, started out of the blue one morning. It was colder out than usual. It sounded like a very loud stuck lifter, and went away gradually as the car warmed up. I used a stethoscope to narrow it down to the drivers side of the engine, but at that time did not know to check specifically for the tensioner. For two days, the noise came back when starting from a cold start. After searching around, I came to the conclusion that it was the timing belt tensioner.

However, now the noise is gone. Even when it is cold outside, the noise does not come back. I was under the impression that when the tensioner went bad, the noise wouldn't go away. Can this problem be intermittent?

For what it's worth, the car has 100k and the timing belt service was done at 90k. I was not the one who did the service, but I am assuming it was replaced then.
* Registered users of the site do not see these ads.
Ryguy32789 is offline   Reply With Quote
Old 09-14-2011, 07:56 AM   #2
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

Don't assume anything. Tensioners, water pumps, and idlers have such a low failure rate that it's NOT par for the course for them to get replaced unless they're showing signs of failure.

Some shops do replace the ~$400 worth of parts while doing the job, but many do not.

If you think your tensioner is getting loose, it's much better to fix it than let it slide. You can pull your accessory belts off, remove the A/C tensioner, remove the crank pulley, remove the timing covers, and put the crank pulley bolt back in with a stack of washers/big nut/etc to hold the crank timing gear in place, then fire your car up and watch the tensioner.
CosmoTheCat is offline   Reply With Quote
Old 09-14-2011, 04:33 PM   #3
rkramer
Scooby Guru
 
Member#: 118209
Join Date: Jun 2006
Chapter/Region: MWSOC
Location: North Dakota
Vehicle:
2002 WRX Sedan

Default

Quote:
Originally Posted by CosmoTheCat View Post
Don't assume anything. Tensioners, water pumps, and idlers have such a low failure rate that it's NOT par for the course for them to get replaced unless they're showing signs of failure.

huhh???

Subaru idler and tensioners have a near 100% failure rate! They fail far more often than the actual belt. Typical DIY'er replacement absolutely includes idlers and tensioners any time you touch the timing belt. A dealer probably will only do the timing belt, customers push back to the increased costs, and it also means additional business later.
rkramer is offline   Reply With Quote
Old 09-14-2011, 06:41 PM   #4
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

Do you work on Subarus for a living? I do. In the last year I've seen perhaps 5 idlers and one tensioner that have failed.

The vast majority of them will last for the normal life of the engine. They do not have a near 100% failure rate, unless you're talking about 300k+ miles.
CosmoTheCat is offline   Reply With Quote
Old 09-14-2011, 07:18 PM   #5
Uncle Scotty
Scooby Guru
 
Member#: 16200
Join Date: Mar 2002
Vehicle:
OK Houston
we have an Uncle

Default

there is no way in a cold frozen over hell that I would change a belt and not change ALL the idlers and the tensioner

no
Uncle Scotty is offline   Reply With Quote
Old 09-14-2011, 10:21 PM   #6
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

Quote:
Originally Posted by Uncle Scotty View Post
there is no way in a cold frozen over hell that I would change a belt and not change ALL the idlers and the tensioner

no
Good for you. Might as well change the oil pump too, since it's only another couple of bolts.


Edit: I'm going to wager that you grew up working on Chryslers and Chevrolets and Fords that had tolerances measured with a wooden ruler.
CosmoTheCat is offline   Reply With Quote
Old 09-15-2011, 11:14 AM   #7
rkramer
Scooby Guru
 
Member#: 118209
Join Date: Jun 2006
Chapter/Region: MWSOC
Location: North Dakota
Vehicle:
2002 WRX Sedan

Default

Quote:
Originally Posted by CosmoTheCat View Post
Do you work on Subarus for a living? I do. In the last year I've seen perhaps 5 idlers and one tensioner that have failed.

The vast majority of them will last for the normal life of the engine. They do not have a near 100% failure rate, unless you're talking about 300k+ miles.
so 6 failures... how many failures do you think there were that you never saw, people either parted the car out or junked it. Given that the car is probably over 100k, there isn't a whole lot of value...

Obviously you work on far more cars than I do, but every single timing belt job I've done on a wrx has had at least one idler that I would have never trusted for another 100k miles. It doesn't take long to search around on here, which represents a MUCH larger sample size than the # of cars you have worked on. Timing belt failures are rare. Idler and tensioner failures are common.
rkramer is offline   Reply With Quote
Old 09-15-2011, 04:56 PM   #8
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

Quote:
Originally Posted by rkramer View Post
so 6 failures... how many failures do you think there were that you never saw, people either parted the car out or junked it. Given that the car is probably over 100k, there isn't a whole lot of value...

Obviously you work on far more cars than I do, but every single timing belt job I've done on a wrx has had at least one idler that I would have never trusted for another 100k miles. It doesn't take long to search around on here, which represents a MUCH larger sample size than the # of cars you have worked on. Timing belt failures are rare. Idler and tensioner failures are common.

6 failures out of hundreds of vehicles that we service. Think about percentages here, not total numbers. Failures are RARE.
This was another topic of conversation in class today, and a regional SOA technical rep agreed with me that failures are rare enough not to bother replacing items that don't show any indications of premature failure.

So there have been what, 100 people on NASIOC who had a failure? Even 200 is still less than .1% of the registered users. That's a pretty damned insignificant number.
CosmoTheCat is offline   Reply With Quote
Old 09-15-2011, 10:26 PM   #9
BKscooby
Scooby Specialist
 
Member#: 163601
Join Date: Nov 2007
Chapter/Region: Tri-State
Location: Brooklyn. NY
Vehicle:
2002 WRX
PSM

Default

Quote:
Originally Posted by rkramer View Post
so 6 failures... how many failures do you think there were that you never saw, people either parted the car out or junked it. Given that the car is probably over 100k, there isn't a whole lot of value...

Obviously you work on far more cars than I do, but every single timing belt job I've done on a wrx has had at least one idler that I would have never trusted for another 100k miles. It doesn't take long to search around on here, which represents a MUCH larger sample size than the # of cars you have worked on. Timing belt failures are rare. Idler and tensioner failures are common.
I will agree with rkramer on this one. It appears that in cold climate regions idler failure is higher.

I for one, had one give up on me, I replaced the belt, idlers and water pump. My friend had the same problem.

Ivery other day I see a post in a newbie section with (noise coming from the motor) which now end then ends up to be a faulty idler on a driver's side.
BKscooby is offline   Reply With Quote
Old 09-15-2011, 10:30 PM   #10
BKscooby
Scooby Specialist
 
Member#: 163601
Join Date: Nov 2007
Chapter/Region: Tri-State
Location: Brooklyn. NY
Vehicle:
2002 WRX
PSM

Default

Quote:
Originally Posted by Ryguy32789 View Post

For what it's worth, the car has 100k and the timing belt service was done at 90k. I was not the one who did the service, but I am assuming it was replaced then.
I would not trust that statment unless it was backed up by a receipt for atleast a purchase of all idlers, waterpump, and the tensioner.
BKscooby is offline   Reply With Quote
Old 09-15-2011, 10:56 PM   #11
AREA1320
Former Vendor
 
Member#: 112508
Join Date: Apr 2006
Location: Easton, PA
Default

Just had one in the other day with a dead tensioner. Another shop didn't replace the tensioner when they did the belt. The car now has 170k on the original tensioner.


That car was number 4 this year with a dead tensioner. So yes they do fail. I see more idler pulley failures however.

I refuse to just "install" a belt. I always to the kits.
AREA1320 is offline   Reply With Quote
Old 09-15-2011, 11:32 PM   #12
Ryguy32789
Scooby Specialist
 
Member#: 214559
Join Date: Jun 2009
Location: Chicagoland
Vehicle:
2005 WRX
OBP

Default

Quote:
Originally Posted by AREA1320 View Post
Just had one in the other day with a dead tensioner. Another shop didn't replace the tensioner when they did the belt. The car now has 170k on the original tensioner.


That car was number 4 this year with a dead tensioner. So yes they do fail. I see more idler pulley failures however.

I refuse to just "install" a belt. I always to the kits.
Is the tensioner replaceable without taking off the belt? It has like a grenade pin in it, right? So could I take off the old one and then slip the belt over the new one before pulling the pin?
Ryguy32789 is offline   Reply With Quote
Old 09-15-2011, 11:51 PM   #13
meebs
Scooby Specialist
 
Member#: 3251
Join Date: Dec 2000
Chapter/Region: NWIC
Location: Lake Tapps, WA
Vehicle:
2009 WRX Hatch
DGM

Default

You aren't 100% sure it's the tensioner. Don't do what I did and just buy parts without having someone else look at it. Sounds to me like you have, "the noise" that a lot of 04/05's have. Piston slap, cold morning clonk-clonk... whatever you want to call it. I did have a bad pulley, but this wasn't the cause of that noise... that god, damned NOISE!!!!

meebs is offline   Reply With Quote
Old 09-16-2011, 07:14 AM   #14
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

Quote:
Originally Posted by AREA1320 View Post
That car was number 4 this year with a dead tensioner. So yes they do fail. I see more idler pulley failures however.

If you only work on a couple of cars per month, then this is a significant failure rate - 4 cars in 9 months.

But if you're busy at all, it's not all that shocking.



Quote:
Originally Posted by Ryguy32789 View Post
Is the tensioner replaceable without taking off the belt? It has like a grenade pin in it, right? So could I take off the old one and then slip the belt over the new one before pulling the pin?
It is possible in theory, but it's not the easiest. You have to clip the belt to the pulleys and/or lock the pulleys together (dohc) to keep the driver's side cams from unloading. Then you have to somehow compress the tensioner without damaging the belt, and even then there's a little tension on the belt.


It's safer and easier to just reset the timing.
CosmoTheCat is offline   Reply With Quote
Old 09-16-2011, 10:32 AM   #15
Nicklz
Scooby Specialist
 
Member#: 94096
Join Date: Aug 2005
Chapter/Region: MAIC
Location: WV
Vehicle:
2003 WRX
WRB

Default

Quote:
Originally Posted by CosmoTheCat View Post
This was another topic of conversation in class today, and a regional SOA technical rep agreed with me that failures are rare enough not to bother replacing items that don't show any indications of premature failure.


Assuming I was stupid enough to go to a dealership to get my timing belt done...
I'd be pissed if 20-30k miles down the road the tensioner or pulley started making noise. And then having the same bill all over again to pay for a tensioner that should have been replaced the first time.
Nicklz is offline   Reply With Quote
Old 09-16-2011, 03:02 PM   #16
Kries
Scooby Newbie
 
Member#: 251604
Join Date: Jul 2010
Chapter/Region: MWSOC
Location: Nebraska
Vehicle:
2002 Subaru WRX
World rally blue

Default



My idler at ~ 90,000 miles.
Kries is offline   Reply With Quote
Old 09-16-2011, 03:23 PM   #17
Ryguy32789
Scooby Specialist
 
Member#: 214559
Join Date: Jun 2009
Location: Chicagoland
Vehicle:
2005 WRX
OBP

Default

Quote:
Originally Posted by Kries View Post

My idler at ~ 90,000 miles.
Wow. Did that cause internal damage? If it didn't, what purpose does the idler serve if the belt can continue to function after a catastrophic failure?

I think I should open up the timing cover and check things out.
Ryguy32789 is offline   Reply With Quote
Old 09-16-2011, 03:34 PM   #18
AREA1320
Former Vendor
 
Member#: 112508
Join Date: Apr 2006
Location: Easton, PA
Default

Quote:
Originally Posted by CosmoTheCat

If you only work on a couple of cars per month, then this is a significant failure rate - 4 cars in 9 months.

But if you're busy at all, it's not all that shocking.

It is possible in theory, but it's not the easiest. You have to clip the belt to the pulleys and/or lock the pulleys together (dohc) to keep the driver's side cams from unloading. Then you have to somehow compress the tensioner without damaging the belt, and even then there's a little tension on the belt.

It's safer and easier to just reset the timing.
We work on many many per day. And to me it's still a high failure rate. I'm sorry but a $150 part shouldnt fail as often as they do.

It's very possible to pull the tensioner without removing the belt. And you don't need to compress the pin either. Just set the timing, mark the belt, lightly clamp the driver side cam gears together with a pair of vise grips and pull the tensioner and replace. It's easy.
AREA1320 is offline   Reply With Quote
Old 09-16-2011, 03:40 PM   #19
Ryguy32789
Scooby Specialist
 
Member#: 214559
Join Date: Jun 2009
Location: Chicagoland
Vehicle:
2005 WRX
OBP

Default

Quote:
Originally Posted by AREA1320 View Post
It's very possible to pull the tensioner without removing the belt. And you don't need to compress the pin either. Just set the timing, mark the belt, lightly clamp the driver side cam gears together with a pair of vise grips and pull the tensioner and replace. It's easy.
I'm having a hard time visualizing this. Do you put one clamp around both cam gears?
Ryguy32789 is offline   Reply With Quote
Old 09-16-2011, 04:01 PM   #20
AREA1320
Former Vendor
 
Member#: 112508
Join Date: Apr 2006
Location: Easton, PA
Default

Right where the 2 gears come close to eachother. Top on at 6 and bottom
One at 12.
AREA1320 is offline   Reply With Quote
Old 09-16-2011, 04:07 PM   #21
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

That sounds sketchy, a little ghetto.

And really? You work on hundreds of cars and 4 failures is excessive?
CosmoTheCat is offline   Reply With Quote
Old 09-16-2011, 05:52 PM   #22
AREA1320
Former Vendor
 
Member#: 112508
Join Date: Apr 2006
Location: Easton, PA
Default

Sketchy? A little ghetto? Lemme guess. You must work at a dealer huh.




Who said hundreds of cars? Let alone hundreds of subarus?

And yes to ME 4 is a lot. Sorry you can't see past that. Are you an A B tech? Or do you just get the lof's and pdi's?

Stay out of this gentlemans thread if you are going to be rude to people and not offer any real help.
AREA1320 is offline   Reply With Quote
Old 09-16-2011, 08:53 PM   #23
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

Many cars per day times a couple hundred days (so far this year) is several hundreds.

I'm a dealer tech, we find ways to spend less time doing a job, but clamping camshaft pulleys together with vise grips just sounds like you're asking for trouble.

Do I just get lof's and pdi's? No, in the last year I've done timing belts, head gaskets, replaced pistons, rebuilt transmissions, replaced wheel bearings, axles, repaired damaged wiring harnesses, and countless other services. I'm not just a lube tech.

Ryguy - pull the drive belts off, pull the timing cover off, and inspect your tensioner. Is there oil around the piston shaft? Put the crank pulley back on and fire it up (cold) and see if it's smacking around.

Setting the timing isn't hard, just take your time and follow the guide around here.


Quote:
Originally Posted by Kries View Post


My idler at ~ 90,000 miles.
That sucks.
CosmoTheCat is offline   Reply With Quote
Old 09-16-2011, 09:30 PM   #24
Nicklz
Scooby Specialist
 
Member#: 94096
Join Date: Aug 2005
Chapter/Region: MAIC
Location: WV
Vehicle:
2003 WRX
WRB

Default

What I thought when I read this
Quote:
Originally Posted by CosmoTheCat View Post
I'm a dealer tech, we find ways to spend less time doing a job, (flat rate hour, we half ass things so we make more money) but clamping camshaft pulleys together with vise grips just sounds like you're asking for trouble. (I'm too good for that, subaru has a special tool)

fwiw that cam gear holder thingy tool is nifty
Nicklz is offline   Reply With Quote
Old 09-16-2011, 09:41 PM   #25
CosmoTheCat
Scooby Newbie
 
Member#: 3409
Join Date: Jan 2001
Chapter/Region: NWIC
Location: Woolley
Vehicle:
1998 Ram 2500
Green.

Default

I've seen some things half-assed, and using vise grips to clamp two pulleys together would be right up there.

We do have a special tool, but really I'd just yank the belt off and reset it.
CosmoTheCat is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
FS:Brand New OEM Timing Belt Tensioner & Timing Belt jsnm Engine/Power/Exhaust 5 04-06-2010 12:58 PM
Funny noise yesterday.... Timing belt Tensioner Bolt Broke!!!! Oh SHAT!!! WRXINTX Factory 2.5L Turbo Powertrain 0 08-09-2008 11:58 PM
More Timing Belt Tensioner Questions papasan Service & Maintenance 2 07-11-2005 01:42 PM
piston slap / timing belt tensioner / knocking noise warranty? jdchmiel Normally Aspirated with bolt-on Forced Induction Powertrain 5 01-20-2004 01:10 AM
Questions about cold start noise/ timing belt tensioner. Please help me. mattrudella Factory 2.0L Turbo Powertrain 1 12-23-2002 10:25 AM


All times are GMT -4. The time now is 01:12 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.