Bypassing the AC compressor

[247]

For the last few weeks, I have been having rattling noises from the engine which I now suspect it could be the AC compressor.

 

Anyways, I was wondering if there is a way to bypass the AC compressor by purchasing a shorter belt for non-air-con system? So I plan on leaving the compressor. Has anyone done this?

 

I am currently using the 1873mm, however there are two for non - AC system: 1450mm and 1460mm ones available.

[mrgf]

Not sure what effect that may have on the cars timing etc! I think its a bit of a risky proposition TBH!

[Jeeves73]

There are a few compressors on ebay pretty cheap why not replace it?

[rum4mo]

On ‎03‎/‎07‎/‎2017 at 21:14, mrgf said:

Not sure what effect that may have on the cars timing etc! I think its a bit of a risky proposition TBH!

 

Affect the timing, I don't think so.  To the OP, maybe have a look at an on-line VAG parts catalogue and see what needs removing and fitting to allow you to run with the correct "no A/C" shorter belt.

 

Remember if the compressor seizes up, it will cause the drive pulley to shear its connection to the compressor internals, so why not just leave it to do that?

[Warrior193]

The valve timing is by a separate, toothed belt. Warning, you could run into serious problems if you leave a faulty compressor to self-destruct as the poster above suggests.

[mrgf]

9 minutes ago, Warrior193 said:

The valve timing is by a separate, toothed belt. Warning, you could run into serious problems if you leave a faulty compressor to self-destruct as the poster above suggests.

Doh!   yeah, your right. I would still be dubious about running it non-standard though. Check with a Skoda dealer if the shorter belt will do ok or if there is more then meets the eye to the whole setup.

[FlexibleMouse]

It will be fine with a shorter belt, you don't want to leave it until it shears off. Just take the belt off first and spin the ac pulley by hand to make sure that's the problem before you buy new belt

[Breezy_Pete]

The A/C pulleys are designed to shear off if the compressor jams up, and just spin freely with the aux belt:

 

 

[247]

Thank you all for the replies. I have managed to record an audio of the noise from the engine. I strongly suspect it's the compressor as the noise only comes on when the heater/air/Ac is on. 

 

What do you think?

engine sound.mp3

[andy-fisher]

I have been running a shorter belt on my Octavia for a long time now with no real issues.  The compressor went shortly after the warranty ran out and the car is now over 12 years old and with 183000 miles on the clock.  The only downside I have found so far is that I'm now pulling dead weight around.

[247]

15 hours ago, andy-fisher said:

I have been running a shorter belt on my Octavia for a long time now with no real issues.  The compressor went shortly after the warranty ran out and the car is now over 12 years old and with 183000 miles on the clock.  The only downside I have found so far is that I'm now pulling dead weight around.

 

Hi Andy,

 

Is it still possible to defrost your windscreen or use other features of climatronic? 

 

I'm I right to believe that  the climatronic uses the AC compressor?

Edited 6 July, 2017 by 247

[247]

Please hear the rattling noise I now uploaded, and let me know what you think. Thanks. 

https://youtu.be/VGobHy7AcAQ

 

[andy-fisher]

It's probably worth checking the alternator pulley, it sounds very similar to when mine seized and the belt squeaked a bit and the tensioner rattled around. It is supposed to free wheel in one direction. The noise only happened when pulling away.

 

I'm unsure about the climatronic. I just have standard a/c (or did). Everything works as it should apart from I obviously don't get cold air.

[andy-fisher]

double post

Edited 7 July, 2017 by andy-fisher

[247]

Thanks Andy.

 

What will be the simplest way to test the pulley on the car? I spun it with the belt off but it seem fine to me.

 

[andy-fisher]

With the belt off you need to stop the insides of the alternator turning and then turn the pulley both clockwise and anti-clockwise. It should only turn one way. If it won't turn either way then it's seized.

 

watch this video for a failing alternator pulley.

 

It's cheaper than a compressor if that is the fault. A seized pulley will also wear the tensioner out quite quickly as there is much more work for it to do.

 

watch this video for a way to test the pulley.

 I get a feeling that if your alternator pulley is the problem then it's seized rather that it being free to rotate in both directions.

[247]

Thanks a lot Andy. I have checked and it is definitely jammed as it's not turning either way.

 

Looking for replacement part, and I'm getting a quote for £60+ for the pulley only from TPS, or a new alternator for £125 including my old unit. I'm contemplating on getting a new alternator instead, as it saves me the trouble of getting the special tool and the hassle of getting it off.  

[Breezy_Pete]

@247 I'm not at all sure your alternator has a freewheel pulley. Compare the appearance of the inside of yours in your photo with those in the videos.

[247]

Hi Wino not sure what to compare exactly but the pulley looks exactly like this

[Breezy_Pete]

The image you see before pressing play on the second of the two videos above is what yours would look like if it was a freewheel pulley. Yours is a fixed one, there's no 'innards' there to do any freewheeling. 

Buy yourself a mechanic's stethoscope for a very few pounds, then you can go round checking each pulley in turn. Makes it quite easy to work out where the noise is coming from.

[247]

Thanks for the advice, it makes absolute sense as i was slightly concerned that my alternator pulley looked a bit different. 

[247]

I think I've found the possible culprit. I'm not sure how I missed it.

 

The movement on the tensioner is not normal, is it?

Please view the YouTube video. https://youtu.be/mk70ImxzAcA

 

Thanks

  

Edited 9 July, 2017 by 247

[Breezy_Pete]

Agreed.

[247]

Cheer Wino, it was an excellent advice you gave me then. Anyway is it also advisable to change the guide pulley with the tensioner?

Thanks.