Noise from fan! Just when it was going so well..

Just when I thought i'd fixed all the problems.... Set off this morning and aweful noise coming from somewhere drivers side engine - like a grating noise - thought initiallyit might be gear box or something. Stopped car and tracked it down to only occur when 1) fan blowing 2) had to be in either demist windscreen or the other setting which basically directs the air upwards. Works fine in all other positions and no noise when in the "up" position without the fan on.

Any ideas?

bonnybrook said:

Just when I thought i'd fixed all the problems.... Set off this morning and aweful noise coming from somewhere drivers side engine - like a grating noise - thought initiallyit might be gear box or something. Stopped car and tracked it down to only occur when 1) fan blowing 2) had to be in either demist windscreen or the other setting which basically directs the air upwards. Works fine in all other positions and no noise when in the "up" position without the fan on.

Any ideas?

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Yup this exact same thing happened to me after driving through a huge great big puddle (insert freelander & water jokes here). You'll get the same noise if you press the a/c button with the fan on.
Not to worry if it's the same as mine it's a really easy fix, it's likey to the the underbody panel that's rubbing up against the drive belt for the a/c. Can't remember which side it was, but think it may have been right side of engine (looking from underneath). I reached up pulled a bit of plastic down and this fixed it!
Oh make sure the engine aint running when you do this!

Good luck!
Norbet

Thanks Norbet
I'll give that a go when I get home - see if I can get under with a torch. Did you need to drop the under belly panel at the back to get at it?

I will also go and try the AC running with the fan and see what the result is.

Gave me a right shock this morning - throught the IRD or auto had packed up - quite a relief (hopefully).

I had a new Powersteering pump fitted last week - maybe he disturbed something - knew I should have done it myself!

- Just confirmed it also makes the noise when the AC is running.

bonnybrook said:

Thanks Norbet
I'll give that a go when I get home - see if I can get under with a torch. Did you need to drop the under belly panel at the back to get at it?

I will also go and try the AC running with the fan and see what the result is.

Gave me a right shock this morning - throught the IRD or auto had packed up - quite a relief (hopefully).

I had a new Powersteering pump fitted last week - maybe he disturbed something - knew I should have done it myself!

- Just confirmed it also makes the noise when the AC is running.

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I suspect it's just a piece of plastic that's catching on the a/c belt/pulley - I didn't need to remove or unbolt the underbelly panel - just reached under and pulled it back down.
If it's not the underbelly panel then something else is caught in the pulley/belt.
I've heard of a cat being caught in the pulley/belt system of a sierra cosworth in the past - customer brought it in claiming of a foul smell coming from the air vents - came as a real suprise for the mechanic!! Quick jet wash/steam clean and all was well - well not for the cat!

Norbet

Nipped home at lunch but couldn't see anything hanging down when I had a look - although it was a mad rush. Definately similar symptoms to yours - same rancid noise when the AC is turned on. Definately a grinding sound, something pastic or metallic i'm not quire sure. Is the AC compressor near the front?

Seems strange it was fine when I pulled up last night - you might be right with the cat!

bonnybrook said:

Nipped home at lunch but couldn't see anything hanging down when I had a look - although it was a mad rush. Definately similar symptoms to yours - same rancid noise when the AC is turned on. Definately a grinding sound, something pastic or metallic i'm not quire sure. Is the AC compressor near the front?

Seems strange it was fine when I pulled up last night - you might be right with the cat!

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Well I didn't get right underneath to check it out, I just reached in on the offside (drivers) where I suspected the noise was coming from and got lucky - I suspect that one of the bolts that holds the panel up at the back may have become loose (after hitting the water hard) and that part of the panel had managed to become folded up at the a/c compressor side of things - see the pic below (courtesy of Northern Irelander)
http://www.landyzone.co.uk/lz/attachments/f9/7318d1222641297-undertray-modified-undertray3.jpg

Having put a convenience hole in the panel for oil services I've not checked to see if a bolt did indeed go missing from the panel, but it's not loose and the grinding noise hasn't recurred since then.

Let me know how you get on with the torch etc - hopefully it'll be an easy fix - and not that you'll need me to tell you (as the noise is unbearable) but leave the a/c off until you have sorted it as you don't want to damage the belt/pulley.

Norbet

Found the source - no dead cat in there fortunately! The splash guard on the drivers side had some how been pushed in to the extent it was rubbing on the AC pump. Pulled it out and secured back in place.

Hell of a noise it made. Not sure really how it ended up like that. I mounted the herb last night before parking and suspect that must have knocked it out. It probably wasn't put back correctly after the PAS pump was changed the other week.

Thanks for all the help norbet - makes running the freebee so much easier!

Just a thought - why does the AC compressor activate when the direction of airflow is "up"? Is this to aid demisting of the screen?

its a design feature - activating screen demist starts the airconn.

The Mad Hat Man said:

its a design feature - activating screen demist starts the airconn.

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Interesting, guess that might have an impact on MPG?

bonnybrook said:

Thanks for all the help norbet - makes running the freebee so much easier!

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That's what the forum's for! You're welcome!

bonnybrook said:

Interesting, guess that might have an impact on MPG?

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A slight one I would think - I'd imagine that running a/c would have more of an impact on smaller cars with smaller engines. If it's of concern switch back to non-windscreen settings once the screen is clear - keeping your screen clean also helps - see seperate thread on de-misting in winter.

Norbet

Had exactly the same vibration noise on our TD4. Mrs Blip spotted that the panel in the o/s wheel well had been pushed back by her last wade.

Cheers

Blippie

Makes a pretty horrid noise - I feared the worst

Nice easy fix.