Air Con Advice

Post by **mat_fenwick** » Sun Oct 09, 2005 7:32 pm

I am fitting air con to my BX, taken from a spares car and was wondering whether anyone had advice on which parts of the system I should replace as a matter of course. Obviously the receiver dryer (bargain £35 from GSF) but I was wondering about the thermal expansion valve and/or the evaporator as they will be difficult to get to once the system is in place.
Secondly, I was advised by a motor factors that the ally sump does not need a gasket - merely silicon sealant. However, the ally sump I have taken off has a gasket in place. Any thoughts?

tom · Post by **tom** » Sun Oct 09, 2005 8:01 pm

The sump and its spacer plate, without which the sump will not fit, are secured with silicone sealant. You do not have to replace the evaporator or, usually the TX valve. Inspect it for leaks around the back where the brass plug screws in. If it is oily outside, unscrew it, counting the number of turns taken to remove it with great exactitude! clean it thoroughly with white spirit and reassemble it, securing the brass plug with a little loctite and use a new green O ring when you do.

Post by **mat_fenwick** » Sun Oct 09, 2005 8:48 pm

Thanks Tom, I have to say I didn't NOTICE a spacer when I took the sump off earlier, I will have to check tomorrow.
And now for my next question... I have been trying to remove the dash. I have undone:
2 nuts under scuttle panel
2 bolts in footwells to the A posts
2 bolts next to steering column
steering column itself
I can now move the dash, but it feels like there is still something to undo. I might be missing something (wouldn't be the first time!) as I am doing it by torchlight, so I would be very grateful if someone could point me in the right direction. Thanks.
One final think - I presume I have to replace all the seals with R143a compatable green neoprene ones? Does this include the internal seals of the compressor?

AlanS · Post by **AlanS** » Sun Oct 09, 2005 10:30 pm

You can usually "get away" with leaving the seals in the compressor. The rest though, must be replaced.
As regards the T/X valve, you can get one for R12 which it possibly has in it, with one for R134a and whilst not necessary is recommended.
You will also require to drain the oil from the compressor and replace it with PAG or an oil R134a compatable.
Always remember that refrigeration oils are all hygroscopic, so do not leave the top off the oil bottle or the compressor for any longer than is necessary and do not under any circumstances open the system in wet consitions.
Also, be sure to check that you have 2 fans attached to the firewall (one each side) or the system won't circulate air.

As to what's holding it; wouldn't be the air ducts by any chance? I take it you have totally removed the glovebox?

Alan S

Post by **mat_fenwick** » Mon Oct 10, 2005 9:07 pm

Update: I now have the dash off - it was the 2 bolts down by the radio that had got me! Thanks for your help.

Tom, I am a little confused as I certainly don't have a spacer between the sump and block. I am guessing that the sump has been off in the past as there is a gasket present, so maybe the spacer has been left off. So, is the spacer required to get the compressor to be in the correct position, or to give an less decreased oil capacity?
Am I right in thinking your sump was off a 16v? Surely Citroen wouldn't make 2 designs of sump for air con cars, one requiring a spacer and one not?

AlanS · Post by **AlanS** » Mon Oct 10, 2005 10:33 pm

I can only speak of the 16V but with them, the actual mounting brackets are moulded into the alloy, whereas with the steel, it's just a plain pressed metal sump.
Oil capacities to my knowledge are the same.

Alan S

Jaba · Post by **Jaba** » Mon Oct 10, 2005 10:34 pm

Not all aircon BXs had the spacer fitted. One day I will find out why. Dunno if the sumps are actually different or not.

But with or without a spacer the gasket was not fitted as standard.

However if the sump is slightly distorted on the block mating surface it may be that a gasket was fitted to stop the leaks.

Hope this helps....I would not worry about it. You will have greater challenges I am sure during the fitting.

Post by **mat_fenwick** » Mon Aug 06, 2007 1:06 pm

As it has been running fine for the last 14 months with no spacer I am assuming that the spacer is not required on the 1769cc engine, but perhaps is on the bigger stroke engines??? As I am doing a 1.9TD conversion I will be using a sump from a 16v engine (originally from a 405 Mi16x4).

Interestingly this seems to be the 4th different design of sump I have seen on the XU engines as this one is aluminium with cast fins. (Hopefully will help with cooling once I up the boost...) Has anyone else come across one before before or did all the 16v engines with aircon have this type of sump?

jeremy · Post by **jeremy** » Mon Aug 06, 2007 1:49 pm

1.7 and 1.9 XUD's have the same stroke as do 1.9 petrols.

Post by **mat_fenwick** » Mon Aug 06, 2007 4:21 pm

OK, thanks.

I knew that the 1.6 and 1.9 petrols had a different stroke; also that the 1.7D (1.

is considered a revvier engine so I just assumed the difference between the two was the crank. In that case I will probably stick to the sump I am using at the moment - assuming it fits on the Xantia engine!!!

Jaba · Post by **Jaba** » Tue Aug 07, 2007 8:08 am

The problem with fitting the spacer - which you may have to do to give clearance for either the pump or the filler tube - is that the hole through it for the filler tube is in the right place for a 1.9 petrol engine. It will not fit on a 1.7 turbo engine without modification of this and the flywheel end too as it actually touches the flywheel and needs a bit of grinding off.
The finned sump is a better sump imho as it gives a bit of extra cooling, but is not as deep, hence the spacer.

As with all things find the one that fits best and use that one.

roscoe · Post by **roscoe** » Tue Aug 07, 2007 12:52 pm

My A/C 16V had an alloy sump with the fins, spacer and compressor mounting brackets cast into place on it. The one I put on my 1.7 turbo TZD with the intentions of fitting A/C to it is off a 1.9 TRi that also had A/C. It does not have fins or the spacer, has the mounting brackets cast in place, and fit perfectly with no modifications. I had a new gasket so used it but silicone would have worked just as well. There is no problem with the filler tube as it does not go into the sump - it goes into the block on the diesel. The sump has a small cover plate bolted on the front of it that has a bracket for the dip stick on some models but obviously not the TRi sold in Oz.

tom · Post by **tom** » Tue Aug 07, 2007 8:40 pm

When fitting the sump from an air conditioned TZI to a 1.7TD, you will need the spacer unless you remove and discard the oil pump. The cast in "rungs" of the spacer will need removing with a hacksaw to fit the spacer to the block unless you remove and discard the oil pump.

Post by **docchevron** » Wed Aug 08, 2007 2:51 am

Removing the oil pump is probably the easiest solution, althougha little shortterm!!!

I fitted the spacer, as Tom says, if you dont, then the sump doesn't fit.

Post by **mat_fenwick** » Wed Aug 08, 2007 11:59 pm

I think I may just swap over the non finned sump, that seems to work fine 'as is'. Don't like making work, got enough jobs lined up to last me a lifetime... I honestly thought the 1.9 had a longer stroke though, so would need to do something to give extra clearance.
From the sound of things, there is an ally sump with no fins that fits without requiring a spacer; and the finned one which does require a spacer.

Thanks for all the help guys!