Me again, an another problem, (front end rattle)

[CitroJim]

Funnily enough, 134a is used as a low power gas in airsoft pistols

I guess because it is safer than butane or propane as intrinsically, R-134a is very safe, non-flammable, non-toxic stuff, even for the ozone layer.

The main risk is frostbite and oxygen displacement resulting from the huge gas cloud it can produce and the amount of heat it absorbs in vapourising If heated to a high enough temperature it can liberate hydroflouric acid which is pretty dangerous stuff.

It appears to be used as a propellent in asthma inhalers and cans of "air duster" but not in anything like the quantity or potential pressure from an automotive A/C.

[Xaccers]

We use propane too as it has a greater expansion so performs better at cooler ambient temperatures. Normally referred to as green gas which is propane with silicon lube and a fragrance.

Would the low pressure sensor on an empty aircon system prevent the clutch engaging?

[CitroJim]

Would the low pressure sensor on an empty aircon system prevent the clutch engaging?

Yes, it would! Good thinking 8)

[TehAgent]

Well, if i can help it, don't want to get the whole pump, just the pulley / bearing assemble that's attached to it.

How does one go about fitting a smaller belt to it? just incase. if anyone knows that is

*EDIT*

Jim i tried that "belt over the pulley" thing, but with out that clutch engaged, the bolt just turns the outta wheel, this isn't looking good.

[TehAgent]

OK looks like my idea to change the pulley is going to be harder than i first initially thought.

Although this post goes to great length in dealing with the bearings, its a bit hard for me to grasp what hes on about with out pictures.

Jim, can you make heads of this?

http://www.frenchcarforum.co.uk/forum/v ... hp?t=19794

[CitroJim]

Ian,

I've had a look and I can see what it is all about and it is not easy. Special tools are needed to extract the clutch and the bearing is expensive. I can see no way around the need of the special tools.

I would seriously recommend you obtain a replacement compressor from a breaker, have yours properly emptied and swap over and then have it regassed.

[TehAgent]

To be perfectly honest Jim, i don't really need Air con, my windows work just as good, so how do i go about, by-passing the motor, with a shorter belt?

I've read in the Air con section that someone managed to do it, but they didn't specify how.

If i can rig it to by pass the Air Con, so i can get it through its MOT with out smoking then i can sort it out after. as at the moment, i only have fiances to sort out the ABS sensor, two new tires on the fronts, the MOT and the TAX that runs out at the end of the month and my insurance.

[CitroJim]

No worries Ian,

Understood

To see if the A/C Compressor can be bypassed easily, drive-wise, You need to determine if a suitable belt route can be found to avoids the A/C pulley and other impediments and one which allows the HP Pump and Alternator to rotate in the correct direction.

If a suitable route can be found, you then need to determine the belt length you'll neeed.

You can acclomplish both these tasks at the same time by using a length of heavy string or a long strip of card to represent a belt (or even your old broken belt for that matter).

You may find you need to remove or reposition one of the jockey wheels to get a suitable route. If and when a route is found, bearing in mind, when looking at the pulleys the engine and HP pump need to run clockwise and the alternator anti-clockwise.

When the route and length is known, go off to your local motor factor and match up a suitable belt. Halfrauds used to be good for this as all theirs were on display last time I looked.

If this all fails, go to a scrappy and look for a non-A/C Xantia and rob it of its tensioners to transfer to yours and try again. I'm not sure of later models but early non-A/C Xantias like my TD had their HP Pump mounted low-down where the A/C Compressor resides. You just may need to move your HP Pump which will be very problematic regarding pipes and mountings.

Hope that helps a little Ian...

[RichardW]

Surely all the ancillaries rotate in the same direction? Your idea is right though Jim, you just need to wrap a piece of string round to see if it will go. The easiest route has got to be as per the existing route, but going straight across from the alternator to the crank pulley, missing out the A/C comp. There is a good diagram in Haynes that shows the belt routing, and a prelim line drawn across here should give an idea of if it's possible.

I never saw my mate's car with the short belt, but he deffo ran it for a while like that - and there was no moving of the alt or HP pump. Like I say though I am pretty sure his had a small guide pulley at the bottom, and this may have helped by wrapping the belt around it.

[TehAgent]

anyone got a photo of that Haynes manual page?

I'm just going to head down to the car now an see if there is a alternative route with the old belt

[CitroJim]

Surely all the ancillaries rotate in the same direction?

I had a vey senior moment there Richard Yes, they do!!!

I'll just get my coat....

[Xaccers]

I may be able to help, I happen to have the haynes manual here at work (don't ask)

Ok, it's not great, but you should be able to see the belt around things.





Eureka!
I think there are two ways to do it, if the belt can be made tight enough to turn the altenator.

If your automatic tensioner is good, take off the manual tensioner with an allen key, run a belt straight down from the hydrolic pump at the front, then the altenator, then the crank pulley, around the auto tensioner as normal, and back to the HP.



OR

Take the belt down the front of the HP to the altenator, up again and over the top of the manual tensioner (the belt would normally go around the bottom of it) then round the crank pulley and under the auto tensioner as normal back to the HP.

[RichardW]

If that's the set up on THe Agent's car, then it's not going to work The belt coming back from the Alt is going to foul the lower of the two tensioner pulleys.

Although.... it might be possible to go crank pulley, top tensioner, HP pump, alternator, allow the front of the belt to rub on the guide pulley (or remove the pulley), then back to the crank pulley. You're only going to get 1/2 turn on the HP pump, it might chirrup a bit, but it should work. Does the bottom pulley move in this set up or only the top - I've not had to work with one of these, only the earlier type set up.

[Xaccers]

If that's the set up on THe Agent's car, then it's not going to work The belt coming back from the Alt is going to foul the lower of the two tensioner pulleys.

Although.... it might be possible to go crank pulley, top tensioner, HP pump, alternator, allow the front of the belt to rub on the guide pulley (or remove the pulley), then back to the crank pulley. You're only going to get 1/2 turn on the HP pump, it might chirrup a bit, but it should work. Does the bottom pulley move in this set up or only the top - I've not had to work with one of these, only the earlier type set up.

The haynes manual fails on this part as with the 1.9TD it shows the lower tensioner being on an arm which is adjusted by a bolt at the bottom of the engine, and although it shows the aircon compressor at the bottom, it points up near the HP for the "air conditioning compressor lower mounting"
Both my 1.9TD and TehAgents are set up like the 2.1TD with the auto tensioner being a sprung piston off the HP and an off centre axled lower manual tensioner.
The doube circle in the middle of the lower tensioner is an allen bolt with a square hole above. As you rotate the square hole around, it adjusts the tension being off centre.

[TehAgent]

Been down to the car and made a quick MSPaint of how my car tensioners and things are set out,

Behold the mighty power of MS paint