Technical high pitch screetch

[zulu705]

Hi,

Long time no post... anyway all well with Sisley until this last couple of weeks.
Everytime I start the car, just as the engine fires into life I get a high pitched screetch noise, very unpleasant and sounds like something needs fixed. I have let go of key at this point and no foot on gas, lasts for a second then all is well.

Any ideas?

Thanks in advance.

 

[Most Easterly Pandas]

Does it do it with foot down fully on clutch and with foot off clutch

 

[default_user]

Loose alternator belt?

 

[zulu705]

Foot off clutch, not tried with foot on, will do later though.

Would a loose alternator belt not do it when it gets wet going through puddles or at other times? At start up is the only time it happens.

Thanks for responses so far.

 

[default_user]

Might just be the fact that the pulley is going at a different speed when you start up and when the alternator catches up the screeching stops. It's worth checking because it will only take seconds to do.

 

[Davren]

Would a loose alternator belt not do it when it gets wet going through puddles or at other times? At start up is the only time it happens.

Quite the opposite, drip water on a screeching drive belt and the noise stops. Often used a test to check if it's the belt that's screeching.

Might be difficult in your case as it only screeches for 1 second? not enough time to tell whether the water stopped it or the 1 second was up.

If the belt feels tight, get your battery tested. A deteriorating battery and cold weather can cause the belt to slip and screech.

Dave.

 

[nitro_warrior]

Replace the alternator belt. Dead easy and almost certainly the problem.

 

[Pandaki]

Loose alternator belt?

:yeahthat:

 

[zulu705]

Thanks all.
Made no difference foot on/off clutch.
Think you are all correct and I will this week take it round the corner to the garage and get a new belt.

 

[VmanC]

Sounds to me like it could be the starter motor, they make this type of noise when the bearings get dry, but if it makes the noise when it's at the garage they'll know straight away if it's the starter or alternator belt.

 

[Davren]

Sounds to me like it could be the starter motor, they make this type of noise when the bearings get dry, but if it makes the noise when it's at the garage they'll know straight away if it's the starter or alternator belt.

Starter motor doesn't have bearings, just a dry bush at each end. They don't turn fast enough or for long enough to need bearings.

Dave.

 

[VmanC]

Wow! did you take that apart just for me.

 

[Davren]

Yeah.... have to go out to my cold garage now to rebuild and refit it to the car.

Dave.

 

[Most Easterly Pandas]

Wow! did you take that apart just for me.

Yeah.... have to go out to my cold garage now to rebuild and refit it to the car.

Dave.

 

[lightweightmick]

This sounds like it could be your timing belt tension roller bearings - see my timing belt replacement guide - you can check it without removing belt by holding your belt under tension with tie wraps - if it feels rough or a little oil under sealing lip cures it, or alters the squeal pitch - get a new one fitted. Alternator belt usually slips more when under more load - ie. with more switched on headlamps etc. (as mine is currently doing at the mo... but that's the least of my worries...)
cheers

 

[zulu705]

Got new alternator belt. So far so good, heard the same noise on first day, but not heard it since.
Thanks for all the suggestions.

 

[urchin]

you sure its not the alternator itself common problem on the fire engines take the belt off and start the engine to see if the noise has gone.