my 1.3lx carb felicia has been making this strange noise for a long time now. when car is idle and i rev i can hear a whining noise. not so loud but if with the windows down i can hear it clearly. when i push the clutch in at the point where the clutch "bites" which is about half way the noise stops. i tried changing the oil to 75W90 api GL4/GL5 semi synthetic (FUCHS) and also tried lucas transmission fix. didnt change the problem. i dont have any problems with gear engagement except for the 2nd gear which i sometimes have to double clutch or wait a second before changing to 2nd for it not to grind especially when cold, gears are a bit stiff. what shall i do ? is this associated to the input shaft bearing ? a very strange thing is when i changed the oil, the first day the noise totally stopped then tomorrow it started again, donno about this very strange. thanks

This was already discussed. Use Advanced Search and look for noise in the title of the topic, only in this section of the forum.

But all the other treads are of 5th gear noise mostly not one of them mentions problem like mine

Not all of them.

Sounds like release bearing to me. No doubt I'm wrong and someone clever will give you a few more clues to the right answer.

Don't give up, Steve. Give the man more clues yourself. Explain to him what makes you think that. Don't let him drift in a sea of uncertainty with 'sounds like' opinions. You can do it. The topic is all yours.

I dontthink that it is the release bearing because it would make the sound once i push the clutch all the way

Could be right.

 

This thread http://www.briskoda.net/forums/topic/247026-very-strange-gearbox-noise/ is about a problem they're prone to on the gearbox input shaft.

 

Were it me, I'd chance chucking a new release bearing on before getting covered in gearbox oil. The boxes aren't bad to get off by any means, but bear in mind if you pull a driveshaft out of the box, it drops the oil.... and stinks!

 

Can you tell I don't like gearbox oil?

I replaced the clutch kit a year ago and a mechanic even tightened my 5th gear nut

jonnycilia

I waited and let other people have better ideas. Since nobody jumped in...

Here's the thing. Do you really want to see what is rattling inside and then solve the issue ? Because the noise will not go away. On the contrary, it will only get worse. The colder outside, the louder the noise. The gearbox will sound like a rusty chain in a pot.

 

First of all, let's clear one thing. It can't be the release bearing. Simply because the bearing doesn't rotate when the car is in neutral or in gear. The release bearing rotates only when the clutch pedal is pressed. Since you mentioned that the noise disappears when the clutch pedal is pressed... the release bearing is out of discussion.

 

So what are we left with? Well, the only thing in motion is the input shaft of the gearbox. So we have two possible causes of the rattling noise:

1. the input shaft bearings (most often the outer one, towards the wheel)
2. any part(s) in contact with the input shaft that developed some play (usually in the 5th gear area where the lubrication is poor: needle bearing 2, bush 3, synchronizer ring 7, spring 8, supporting ring 13, synchronizer body 9, outer nut 11)

If the outer nut is loose, the gearbox has a whining / whistling sound when the 5th gear is engaged. That is not the case with your car.

 

The rattling noise is present in cars having the old model of gearbox (10S). Newer model (14SK) is much better designed and built.

 

 

There is only one way that I know of to find out what is wrong without removing the gearbox. Here are the steps:

• jack up the front of the car and support it properly on jack stands
• remove left wheel
• drain the oil from the gearbox
• remove the mounting plate of the gearbox to drop it, support the gearbox with a jack and lower it
• remove the housing cover of the gearbox - 5th gear area is now exposed

Now comes the fun part. Try to do this part when the gearbox is totally cold.

• use a bright lamp to light the area
• ask a friend to start recording a video of the whole process
• start the engine, gear in neutral
• observe and listen closely the movement of parts; use a stethoscope for mechanics
• push the parts that might be rattling with a stick, trying to minimize the noise
• press the clutch pedal, then release it, observe the changes

The instructions in blue will document this mystery noise for thousands of people having the same problem in many countries.

How easy is replacing the gearbox outer bearing of input shaft ? Does it need any specific tools or just remove and replace ?

Medium difficulty. You need a bearing extractor, a press, pliers for circlips, socket wrenches, a pin punch, a chisel, and a feeler gauge.

 

Here are disassembly and assembly videos of a similar type gearbox.

 

https://www.youtube.com/watch?v=-yfICJKkLhE

https://www.youtube.com/watch?v=9GjP2tMLVbQ

 

But in 80% of the cases that I know of, it wasn't a faulty bearing.

Oh better leave it alone i think its not worth the work thanks ricardo. Thisvthingvis strange because like 2 years ago i took it to a mechanic to fix my 5th gear problem, it got fixed then not much long after the gearbox started whining not only in 5th but in all gears :P

Donno if its normal but my box shifts hard when cold, especially from 1st to 2nd i usually rev between gear change to overcome the grind

Donno if its normal but my box shifts hard when cold, especially from 1st to 2nd i usually rev between gear change to overcome the grind

That sounds like you might have worn synchromesh cones. You might be able to improve the gear change by changing the gear oil (use a multigrade if one is available).

Thisvthingvis strange because like 2 years ago i took it to a mechanic to fix my 5th gear problem

What 5th gear problem did he fix?

Were you present during that repair? Because that's not a repair but more like a 'fix it with a sledgehammer' job.

 

Donno if its normal but my box shifts hard when cold, especially from 1st to 2nd i usually rev between gear change to overcome the grind

Yep, synchro rings 1/2 failed.

Edited 18 December, 201510 yr by RicardoM

No i wasnt present during the repair. I use fuchs 75w90 api gl4/gl5 semi synthetic oil

For the 5th gear problem i mean the whining noise he told me the nut was loose and he tightened it donno if he used new nuts

No i wasnt present during the repair. I use fuchs 75w90 api gl4/gl5 semi synthetic oil

Ideal oil. If the last time the box was drained and refilled was over 80_000km (50_000miles) ago a drain and refill might still help.

 

Beyond that, what you're doing by rev matching during gear changes is the best you'll do short of a rebuilt or exchange box I think.

For the 5th gear problem i mean the whining noise he told me the nut was loose and he tightened it donno if he used new nuts

No i wasnt present during the repair. I use fuchs 75w90 api gl4/gl5 semi synthetic oil

Oh yeah... we all know how things work in most garages when the client is not present at all...

The whining occurs when the gears don't mesh properly from wear or loss of alignment. Look for a better gearbox.

You're right on that ricardo, for now ill just rev match lol been rev matching for 2 years now gears rarely grind. I just refilled my box 50 miles ago with fresh oil. I think in the future i may better look at a used gearbox than a rebuild cause its much more expensive right ?

You missed the opportunity to see if it is an easy fix for the strange noise. It could be just those 2 circle springs that lost strength. Czechs say on their forum that is the most usual issue.

 

Edited 19 December, 201510 yr by RicardoM

what 2 circle springs ? how can i fix them ?

http://www.briskoda.net/forums/topic/381437-strange-noise/#entry4468549

3rd paragraph and illustration.

Edited 20 December, 201510 yr by RicardoM

And one thing i noticed since i changed my engine oil at my last service was i had a knocking noise which lasts 2 seconds at cold startup only. I used shell helix 15w40 now i used fuchs 15w40 and it disappeared. Starts much smoother also, gonna stick with fuchs oil at my oil changes