BX problems
Moderator: RichardW
BX problems
A bit of background first--I've had my BX out here in Saudi Arabia for about 8 years-It's an 88 mk2 16TRS-I do all of my own servicing as there isn't a Citroen garage here-I get back to the UK every 3-4 months,so I have to make sure I have everything I need to do each job before I come back out here-I'm back in UK in January and I've got two jobs to get parts for-refurbishing the rear arms and a problem with the air conditioning--can anyone tell me exactly what I need to do the rear arms? I've got the classic leaning wheels and creaking from the rear end,so I'm fairly sure that it's the rear arms at fault--the problem with the a/c is that even though the system charges ok,there isn't much in the way of cold air coming into the car-the "experts" out here tell me that it's the valve under the dash that's the problem? I've checked with my local Citroen dealer in UK who says that there is a valve behind the dash but they are'nt sure what it does!!I know that few BX's sold in UK had a/c but does anyone know what might be stopping the cold air? I need the a/c as it gets quite hot out here!!!I'm an aircraft engineer by trade so I'm not too bad with the technical stuff!!Here's hoping that there is an a/c whiz out there------philcut <img src=icon_smile_cool.gif border=0 align=middle><img src=icon_smile_question.gif border=0 align=middle>
Here you go Phil, these are a couple of sites that may be of some help re: Rear arm bearings.
http://www.bx.citroen.org/m07/m07e.html
http://members.fortunecity.com/werkplaa ... agers.html
Between them they should either show or explain everything you may need.
Regards the air/con that could be a bit trickier based on the symptoms given. The valve you are referring to is a TX valve (thermostatic expansion valve) & assuming it's a RHD car, is accessible by removing the actual glovebox they tell me on a 16 Trs.
It's job is to act as a restricion between high pressure & low; it is the point where high pressure refrigerant is restricted as it passes through a small oriface at which point it boils off as it invades the space inside the "Evaporator" (named for obvious reasons) which is in fact the cooling coil, and during this 'boiling off' it evaporates and in the process absorbs heat. The gas, by this stage in vapour form, is then returned to the compressor by the suction (or return) line, recompressed & disperses its heat as it passes through the condensor where it then (naturally) condenses.
I've given that quick summary to help you to diagnose it.
Effectively: If the TX is jammed open, the head pressure will be 'down' whilst the backpressure (suction) will be up. There will be signs of condensation & moisture on the suction lline back to and may even be evident on the compressor.
If the TX is jammed fully or partially shut, then the opposite will apply. The head pressure will be astronomical whilst the back pressure dcould be so low as to be into vacuum. I would like to be able to say that your car would have switches to prevent the compressor from running after certain pressures are reached in either of these two scenarios but unfortunately, I've found that each Country's legislations are different on this.
Similar symptoms will be found if the receiver/dryer is either clogged or if you have moisture in the system, however, in the latter case everything will seem to be operating OK and then it will go haywire without warning.
Also, are the two fans both working on the condensor of the air/con? That can also lead to excessive head pressures & cause safety switches to make the system short cycle. Switch on air/con, step outside car & see physically that BOTH are operating. One makes as much noise as two & can be misleading as I found out on one of my own cars.
Also, what gas is your system on? If it's been converted to R134a check that the components have been replaced that require it & if not find what kind of gas they have available there to regas when you get it fixed; most important when you are buying air/con parts these days. If R-12 is still available, that would be the original in that system & if they still use it over there then no problem. There is a gas that "goes over" R-12 that again eliminates much of the drama, but if they are only using 134a, you'll be up for a full conversion.
If you are getting the whole system redone there & want to get the bits from UK, you'll need a TX, a receiver/dryer and in the case of a full make over, hoses too.
Without being flippant, bearing in mind where you are, I should warn that the receiver dryer does tend to look like a bomb of sorts & may cause a bit of concern if a baggage handler happened to spot it on luggage scanner if you or a friend happen to decide to bring it in via your luggage.
As regards you being able to fit these parts yourself; a vacuum pump and gas refilling system would be required as these systems as with all refrigeration units, must be fully evacuated of air & be totally contaminent free particularly of atmospheric moisture.
Hope that is more help than confusing.
Alan S
http://www.bx.citroen.org/m07/m07e.html
http://members.fortunecity.com/werkplaa ... agers.html
Between them they should either show or explain everything you may need.
Regards the air/con that could be a bit trickier based on the symptoms given. The valve you are referring to is a TX valve (thermostatic expansion valve) & assuming it's a RHD car, is accessible by removing the actual glovebox they tell me on a 16 Trs.
It's job is to act as a restricion between high pressure & low; it is the point where high pressure refrigerant is restricted as it passes through a small oriface at which point it boils off as it invades the space inside the "Evaporator" (named for obvious reasons) which is in fact the cooling coil, and during this 'boiling off' it evaporates and in the process absorbs heat. The gas, by this stage in vapour form, is then returned to the compressor by the suction (or return) line, recompressed & disperses its heat as it passes through the condensor where it then (naturally) condenses.
I've given that quick summary to help you to diagnose it.
Effectively: If the TX is jammed open, the head pressure will be 'down' whilst the backpressure (suction) will be up. There will be signs of condensation & moisture on the suction lline back to and may even be evident on the compressor.
If the TX is jammed fully or partially shut, then the opposite will apply. The head pressure will be astronomical whilst the back pressure dcould be so low as to be into vacuum. I would like to be able to say that your car would have switches to prevent the compressor from running after certain pressures are reached in either of these two scenarios but unfortunately, I've found that each Country's legislations are different on this.
Similar symptoms will be found if the receiver/dryer is either clogged or if you have moisture in the system, however, in the latter case everything will seem to be operating OK and then it will go haywire without warning.
Also, are the two fans both working on the condensor of the air/con? That can also lead to excessive head pressures & cause safety switches to make the system short cycle. Switch on air/con, step outside car & see physically that BOTH are operating. One makes as much noise as two & can be misleading as I found out on one of my own cars.
Also, what gas is your system on? If it's been converted to R134a check that the components have been replaced that require it & if not find what kind of gas they have available there to regas when you get it fixed; most important when you are buying air/con parts these days. If R-12 is still available, that would be the original in that system & if they still use it over there then no problem. There is a gas that "goes over" R-12 that again eliminates much of the drama, but if they are only using 134a, you'll be up for a full conversion.
If you are getting the whole system redone there & want to get the bits from UK, you'll need a TX, a receiver/dryer and in the case of a full make over, hoses too.
Without being flippant, bearing in mind where you are, I should warn that the receiver dryer does tend to look like a bomb of sorts & may cause a bit of concern if a baggage handler happened to spot it on luggage scanner if you or a friend happen to decide to bring it in via your luggage.
As regards you being able to fit these parts yourself; a vacuum pump and gas refilling system would be required as these systems as with all refrigeration units, must be fully evacuated of air & be totally contaminent free particularly of atmospheric moisture.
Hope that is more help than confusing.
Alan S