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MiniMental
26-07-2016, 09:48 AM
Hi guys n gals,

On Saturday I spent £360 on a new LUK DMF and clutch etc and fitted it all. Car drives perfect. Feels like it's just left the showroom. Which leads me to my issue, when the clutch isn't pressed and during engine braking etc it's still making a lot of noise. When clutch is pressed, poof! Noise gone. Given that everything is brand new and genuine, is there any common causes of this? Is it just it all bedding in or...??? Need help please because it's driving me crazy and I don't want to wreck the new DMF/clutch that's skinted me...

Kind regards
Aidan

Vehicle:

2005 Passat Variant 130pd 5 Speed AWX/012..

Fitted:
New Release Bearing,
New DMF
New bolts
New clutch p/p and f/p
New crank seal

Installed with a torque wrench not a breaker bar [emoji106]

Works perfectly, just worrying about the noise...

Mowerman1967
26-07-2016, 08:50 PM
Dunno if it helps but when mine went recently and was replaced it didn't make any odd noises or need bedding in, it went great straightaway.

zollaf
26-07-2016, 08:55 PM
^^^^ wot he said ^^^
what noise is it making. sounds like something more sinister might be going on. was the old dmf properly worn out ?

MiniMental
26-07-2016, 11:09 PM
Old DMF wasn't good. In first it juddered like nothing else and in reverse it pretty much just stalled unless I revved the **** off it.... It's all smooth as pie now... Feels beautiful...

Only does it with clutch pedal out... Which in my mind narrows it down to release bearing or input shaft bearing?? Spigot bearing would be noisier with clutch pressed so doubt it's that... Dare I ask, how hard is input shaft bearing to replace...

It's like a whirring shhhhh sort of noise :S

Any input appreciated.. If it makes any difference, I can't remember greasing the face on the release bearing...

Aidan

grant19841
27-07-2016, 01:04 AM
The metal gasket between the engine and bell housing, are you sure this has not been damaged?

I have seen this before the gasket gets bent,
on installing of a floor jack and wrestling gearbox back in. The metal gasket can kick out and rub against the flywheel causing a horrible sound!!




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grant19841
27-07-2016, 01:09 AM
Or a bend spring finger on the clutch?


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MiniMental
27-07-2016, 07:49 AM
Thanks for the reply bud [emoji846] I can't see it being the gasket as it would be noisy all the time, and the gearbox flew back in, so I also doubt the PP is damaged, I'll do a test on my way to work this morning, if I press clutch and select 3rd or 2nd gear at 50-60mph, input shaft will spin FAST (obviously not release clutch), if this makes a lot of noise I think it would highlight input bearing failure :/ what a ball ache... Not exactly an undemanding job taking box off on my mates garden lol.

zollaf
27-07-2016, 09:10 AM
doing that will also spin the clutch plate up to incredible speeds, far more than its designed to take and can result in it shattering.

Sam
27-07-2016, 09:30 AM
doing that will also spin the clutch plate up to incredible speeds, far more than its designed to take and can result in it shattering.

A lady I used to work with once mistakenly selected 2nd instead of 6th in a Volvo travelling at speed. The car tried to do a forward roll which somehow resulted in the gearbox being dumped on the road.

MiniMental
27-07-2016, 09:51 AM
A lady I used to work with once mistakenly selected 2nd instead of 6th in a Volvo travelling at speed. The car tried to do a forward roll which somehow resulted in the gearbox being dumped on the road.

That's only gonna happen if you take your foot off the clutch though bud, tried it. Couldn't hear much, still non the wiser.

If I press pedal whilst stopped at idle, noise takes about a second before it vanishes and comes back instantly when you reach bite point on the way up, if I select a gear and slip clutch as if in going to set off (keeping input am shaft still) there's no noise.

FrenchAudi
27-07-2016, 12:10 PM
I have a similar noise on my 1994 Alfa, which also has an in-line engine and gearbox, with a clutch arrangement much like VAG, but without a DMF.

I bought the car 4 years ago with 50,000 miles, little used by an aged owner. It has now done about 65,000 miles.

I noticed the noise shortly after I bought the car and decided it could be the release bearing, but more likely the input shaft bearing, as, like yours, the noise stopped when the clutch was depressed.

The clutch failed early in 2015. I got around to repairing it in January this year, and found the release bearing had partly seized and chewed through most of the diaphragm fingers, probably due to rust forming in the bearing while unused for so long before I bought it.

I replaced the complete clutch and release bearing, and also checked the input shaft for oil leaks and play, but it seemed OK. I noticed some slight wear marks on the top and bottom of the spigot which guides the release bearing, so I refitted this in its support so the wear marks are now at the sides.

The noise is still exactly the same as before I replaced the clutch:(and still stops when the clutch is depressed.

It could be the input shaft bearing, but could also be the release bearing rattling on its spigot, the release lever rattling against the gearbox housing, or even the input shaft splines rattling in the pressure plate.

The noise has been the same for 4 years now, I can only hear it when the car is stationary, and I'm not going to do anything about it unless it gets a lot worse.

MiniMental
28-07-2016, 11:12 PM
Think it's definitely input shaft noise. I don't understand why it's so amplified under engine braking in 3rd, 2nd and 1st when moving down through the gears to a stop... The giveaway for me is that when idling on the drive it's noisy till I press the pedal, then it takes a second for clutch to stop spinning and noise goes. If I let it up to bite point in neutral, noise is instantly back again. If I repeat the same whilst in gear, I feel the clutch bite but there's no noise. Silent. Whe it's noisy its like bad wheel bearing noise with a slight rattle...

Any input welcome. Am I looking at another box given the effort needed to get it off or is it an easy fix once off?

Cheers
Aidan

FrenchAudi
29-07-2016, 08:21 AM
I agree it is most probably input shaft noise. But it could possibly be caused by backlash between a pair of the constant mesh gears when they are unloaded, or even damage to these.

I'm going to check the gearbox oil level, just in case that is a factor.

The Alfa has a two-part input shaft with a splined coupling between the parts, so that is another possibility for me, but your input shaft should be one piece if it is similar to the corresponding Audi item.

If so, it is possible to replace the input shaft bearing without dismantling the box, but this requires a couple of special tools. See 5-Speed Manual Gearbox 012/01W Front-wheel Drive (http://workshop-manuals.com/audi/a4_mk1/power_transmission/5-speed_manual_gearbox_012/01w_front-wheel_drive/gearbox_mechanicsoperation_constructiondiff./dismantling_and_assembling_gearbox/removing_and_installing_input_shaft_ball_bearing_m ulti-function_sender_input_shaft_pinion_shaft_selector_ rods_and_gearbox_co/)

FrenchAudi
03-08-2016, 02:07 PM
It may not be much use to you, but I think I have found the cause of my rattling noise as being from backlash in the gearbox due to uneven idle speed.

The engine is idling at about 750 rpm, a bit lumpy with some hestation, but when I increase the idle to just under 1000 rpm the noise stops completely.

As the idle speed is controlled by a module which varies the volume of air through a throttle bypass I shall have to clean this up or replace it, but at least I know I don't have a terminal engine problem.

I suggest your noise is due to the input shaft front bearing, as you think, or damage to one or more gears. As I posted above, you may be able to change the bearing without stripping the box.

MiniMental
03-08-2016, 06:15 PM
Yeah I'm gonna have a look. In for four new tyres on Monday, coupled with clutch and DMF that's me all spent out this month lol. It's makes no difference with engine speed on mine. Only stops when I press clutch as standstill. Mine being diesel, idle is controlled by fuel not air, I do have a 'notchy' idle when cold, but only for 10 seconds or so.

Thanks for the suggestions though, it is much apprecatied. I think I'm gonna source a box off eBay and swap the entire thing when I get chance.

FrenchAudi
03-08-2016, 09:48 PM
I'm not sure I'd trust a secondhand box, unless I were sure it came off a very low mileage accident write-off.

I think, if possible, I'd get an exchange 'box and return mine after fitting it, or buy a secondhand one and have that rebuilt.

All depending on how much work you want to do fitting 'boxes, and the costs involved.

MiniMental
03-08-2016, 11:30 PM
Seen a few 67k milers on eBay for around £150 mark with 3 months guarantee. I think I'm unlucky tbh, from what I've seen and heard, vw boxes are usually pretty bullet proof. Second hand box isn't gonna be any worse than mine lol. Not hard to change. Some trim a jack and a few bolts.. Lol. We'll see. Car is getting on and needs loads doing. A recon box would likely push the boundaries of what it's worth...

In need of:
Exhaust
Shocks
Rear brakes
Four tyres (Monday)
Headlight polishing
Extensive Stone chip repairs
New rear bumper trim (struggling)
All new door locks
Front wheel bearings
Cambelt
Water pump
Gear gaiter
Gearbox (evidently)

Nothing drastic, all cheap and easy enough but not all at once lol [emoji15][emoji15]

MiniMental
03-08-2016, 11:33 PM
Oh, starter motor and rear wiper motor... Starter motor sticks out when starting for a second or so and I snapped the washer tube off inside wiper spindle on the back.... Wouldn't mind, but I did it at the end of refurbish the whole wiper motor Assy as in to tight to buy another. Works good as new now except the washer lol.

It's a labour of love but I love the car too much to give up... Fantastic to drive and at the age where it's modern and economical yet easy to work on at home, not just a bundle of electrics which needs a garage all the time.... Think I'll have it for life. Lol.

MiniMental
03-08-2016, 11:35 PM
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