Smoke, Ping and Beep-Beep!!!

[Chris56000]

Hi!

When coming back from a Computer Fair yesterday my HDi 406 110 suddenly gave out a puff of smoke from under the bonnet near the alternator etc, as I was pulling into a lay-by for a coffee, then the centre console flashed up "BATTERY CHARGE FAULT" with the ign. light lit and two beeps from behind the dash!!!

I had a ferret underneath to check all the hoses, rad etc., to see if that anything had gone pop, didn't find any obvoius cooling problems (no burst hoses, rad leaks etc., etc., temp gauge reading about 80!!!) but found the alternator serpentine belt had snapped, presumably this was what had smoked!!!

1) I had breakdown cover provided by my insurer, the RAC chappie who attended thought it was the air-con compressor had jammed and snapped it, so he arranged a recovery truck!!!

2) Are these compressors known/problematic for jamming or sudden failure? I found a good one on fleabay for £35!!! I did try spinning the a/c pulley, alternator pulley and tension roller by hand, nothing felt rough or noisy tho!!!

Could I get away with isolating the a/c clutch electrical supply so I can get to and from work in the meantime until I can get the compressor replaced and regassed?

2) The belt looked well past its first flush of youth, but it looked like a clean break with no bits or fragments gone inside the cam-cover etc to cause horrendous further damage!!!

3) Anything else known to cause serpentine-belt breakage in '406 HDi 110s and anyone else had this?

Can anyone tell me if I'll need anything else besides the belt?

Chris Williams

[spider]

Has it actually seized then ?

If you unplug its electrical connector on the it the compressor clutch cannot engage so it should freewheel effectively.

Not tested I must add.

[CitroJim]

It is likely the aircon compressor is the culprit. Although counter-intuitive in this prevailing cold, if the heater is set to full demist then it is likely the aircon will be running provided the evaporator temperature is high enough. Airconned dry air is a very effective demister.

Normally, an AC compressor gives you lots of warning of seizing. The get noisy and you can feel them dragging down the engine. Having said that, a full-on seizure is rare and more commonly, the clutch bearing fails, causing the pulley to jam up and go way out of alignment. It sounds like this part is fine in yours Chris.

As Andy says, you can disable the A/C very easily by disconnecting the two pin plug on top of it feeding the clutch.

When the new belt is fitted, test the A/C by idling with the A/C off and then engaging the A/C. Be ready to kill the engine instantly. If the A/C compressor is seized, there is a good chance it will stall the engine when it cuts in. Be aware the A/C won't cut in until the evaporator is warm enough to prevent it icing up.

[panason1c]

2) The belt looked well past its first flush of youth, but it looked like a clean break with no bits or fragments gone inside the cam-cover etc to cause horrendous further damage!!!

Probably just a well used and worn out belt that finally gave up.........just fit a new belt and i'll bet all is well...

[Chris56000]

Hi!

Sorry - I'd mixed up the steering pump with the compressor, not realising the compressor (appears to be delphi!!!) is at the bottom, and trying to turn the bottom compressor pulley by hand results in a dry scraping noise!!!

Is that an indication of failure, (replacement off fleabay not arrived yet!!!) and if so, is it possible to actually dismantle the clutch/pulley assembly to see if it's salvageable once I've got the replacement fitted?

Chris Williams

[CitroJim]

Sounds like the aircon compressor is unhappy Chris. Specifically it sounds as if the compressor clutch bearing has failed. With the clutch disengaged the pulley should rotate freely (very freely) and with no noise or play.

Basically, yes, they can be repaired but depending on the model, special pullers are needed to get the pulley apart and then there is shims to adjust when reassembling it with a new bearing. Most either re-route a new (shorter) auxiliary belt to bypass it or go for an exchange compressor.

There's a thread in the aircon section of this forum with more information and in the Citroen forum there are some posts on bypassing the compressor. Look for posts by MikeT on this subject.

[Chris56000]

Hi!

Yes - it happened again - "Snap - Ping and Beep-Beep!!!" again in Ikea's Car Park in M. K. on the way into work from my sister's in Saffron Walden!!!

I got the breakdown lot out again and this time the a/c pulley had jammed solid!!! £102.50 poorer and four hours later I was on my way again with the replacement compressor from fleabay fitted and yet another belt!!! The a/c pulley on the replacement did spin freely without any nasty noises by the way!!!

If I leave the replacement compressor disconnected will it be OK to get me to and from work until I'm paid and can afford to get it checked and regassed/relubricated?

Chris Williams

PS!!! I had a look at the wiring diagrams and there doesn't seem to be a dedicated a/c fuse or an easily accessible a/c pressure switch in the system anywhere!!!