XSeries-forum

Just driven from Salisbury to Luton... for my sins...

And rolled up at filling station... whereby the battery/charging light came on followed by smoke & burny rubber smell from under the bonnet...
Turned out that the A/C pump had siezed & the belt was burning away from the crank pulley turning...

I turned the A/C off at the dash & the clutch dissengaged & allowed the belt to move again & all was OK...(ish)

The AC system was re-pressurised a week ago... and nothing to report there..

What would cause an AC pump to sieze... and can the be free'd off or lubed etc ... or is it the expected removal & replacement job ??


The AC wasnt working previously, and I kept it on just to keep the seals supple...
But now its knackered it seems...

Any one know much about these items ??

Regards
Grant B

Your not having much luck atm Grant sounds to me like it might be a replacement but not 100% sure not had much to do with AC only re gas.

Tim

Not your year with that car is it?!

If it's seized then the oil may have leaked out and it's a specialist job to repair the unit.  I think the compressor is made by Denso so see if you can find a repairer, otherwise it's going to be about another £400 or so off your bank for a new one (not from a dealer as they will want more than that!  Second hand units are a lot cheaper.

As well as degassing/regassing, you'll need to flush out the dryer too.

R

"What would cause the AC pump to seize"
Knackered bearings, it's likely that there was a tell tale noise coming from the pump prior. You'd likely need a puller to remove the old bearings, thats if you could source the correct size to replace them with and from what I've read it's a bit of a PITA job.
Best option would be a replacement part from a breakers if you want to keep the cost down.
You've been unlucky, an ac pump often lasts the lifetime of the car.

When a re-gas is done professionally, my understanding is that they should evacuate the system entirely, and leave under vacuum for a period to test for leaks. Then add the correct weight of refrigerant and oil. is it possible the oil was not added?

The bearings in your compressor pump will not be connected to the gas in the system, they will be sealed bearings

Do you think its possible that the air con compressor could have a hydraulic lock and be jammed by liquid... not necessarily a mechanical failure ?? As it was regassed a week ago !

It gave no hint what so ever of a bearing failure seizing... no unusual noises etc.

Wondering if its worth decompressing the system and seeing if it free's up the pump ?

Thoughts ?

I'd be surprised as I thought the refrigerant used (R134a?) boiled at -26C so it would not be liquid for very long.  Worth checking the pressure with a gauge to see if it is too high.  I know when I mine the recharge cylinder had to be used upside down to ensure both lubricant and gas was fed in with the system running.

It may just be sheer coincidence that your pump has packed up within days of being done, the same as sometimes happens with the auto gearboxes after an oil change.  Try going to another AC Specialist and see what they think.

Richard

Hi Richard,

A local Indy had the vehicle in bits, as I can earn more by working than the labour costs in weekdays...
Any way, turns out that the plastic layer between the Crank pulley centre & outer has let go... almost like a dual mass flywheel...

so the additional load of the AC was sufficient to allow the two parts to melt down even more and thereby stop the alternator turning too.....
that was until the outer belt pulley guide almost fell off the front of the engine and the air con belt its self dropped off completely..
It would appear that the AC pump is ok and intact...

Never had one of these pulleys separate before.... but there's a 1st time for everything with an X5 lol...

Hopefully the X5 will be in one piece today, as I used the company pool car to get home last night -
A butt-bottom of the range under powered Zafira....
bloody awful thing, nasty in every conceivable way... but better than walking home lol

That's a relief......and all being well no more Zafira.. )

Got the Zafira again tonite...

A budget crank pulley now, or a decent OEM one for £45 more at 4pm...
For the peace of mind I will have the better one and wait till tomorrow for my beast !

Cant be done with cheap bad parts & walking places for cutting corners later on.

I do some 4500 miles a month, and need the reliability...

Much cheaper than a compressor then! Unusual problem, haven't heard of that one before.