6+2 pump (Xantia w/out flo-dis) on BX - anyone fitted one

DLM · Post by **DLM** » Wed May 02, 2007 1:59 pm

As a number of people seem to be putting 1.9TDs into BXs, some must originate from Xantias, and would have had flo-dis-less power steering setups. Has anyone here done a conversion which includes this?

Also, has anyone here done the flo-dis-less conversion and omitted the 1.9TD (my preference)? I know it needs manual-style PR, the pump displaced into the Xantia or XU petrol BX next-to-reservoir position taking rotation from the alternator pulley, an extra valve, and all sorts of interconnectionry. I'm not necessarily going to do it, but I know someone whose BX I repair that might appreciate it if it's a goer in practice.

jeremy · Post by **jeremy** » Wed May 02, 2007 2:08 pm

Vanny did it didn't he?

How difficult on a diesel is it to fit the pulley and pump to a 1.9 engine? Do you have to use a 1.7 camshaft or can the existing one be used? The reason I say this is that the ZX has a brake vacuum servo pump driven from there.

My comment on the ZX arrangement is - probably like many other similar cars - what a daft arrangement. Why not fit it with fully powered brakes driven from the PAS pump and eliminate the expensive vacuum servo! Do it properly and the electric pump for the ABS can be eliminated as well.

Vanny · Post by **Vanny** » Wed May 02, 2007 4:28 pm

well its reasonably easy. Easier still if you find a non aircon donor!

pump location
In my case i used a 1.9td which formerly had aircon, and this was the first significant problem, on the xantia if the car has aircon then the HP is right at the top, then the alternator then the aircon all at the cambelt end of the engine, however the mount for the alternator is nothing like that on a the BX and sticks out quite far ie touches the radiator which isn't good. Non aircon xantia use a different setup with the hp pump lower than the alternator leaving suffcient room for plumbing etc. The bolts for the HP pump and alternator mounting appear to be on ALL XU engines 9petrol and diesel) whcih stands to reason and should make fitting a doddle!

Belts
Belts are a little tricky as the HP pump from a xantia have a 6 tooth belt, however you can get a 5 tooth crank pulley and alternator for a bx and this will work fine with the xantia hp pump. Assuming you didnt go use an aircon equipt donor then the routing of the belt should be pretty easy and you should be able to use the tensioner device from the Xantia

low pressure plumbing
well youre going to need the xantia PR and accumulator still which might mean a slight extension to one of the big low pressure return pipes, however the supply to the HP pump can be made up using that originally fitted to the BX and shortened. It is likely that you'll need a 90 degree bend in whihc case simply use a plumbing bend. The trick here is that hose for the LHM is standard fuel hose so anything you can do with fuel hose you can do for routing the LHM!

High pressure plumbing
This is where it gets difficult! The twin output xantia pump has a 6mm feed which goes directly to the PAS rack (which has a 3.5mm fitting). I sorted this by taking the pipe from the xantia (its a big long one with a flexible mid section) and routing this around the engine bay to the rack. This required CAREFULL heating and bending of the pipes, i pretty much failed to do either and left the pipes in a bit fo a mess and if the MOT man notices he likley wont be happy.
Now that 6mm to 3.5mm problem, well all the xantias i've looked at have a 1 inch extension boss which screws into the PAS and the feed pipes screws into it, simply i welded a 3.5mm coupling on the end of the boss, and VERY carefully drilled it back out, and it worked perfectly first time. I used to have a pieve of small diameter pipe with an olive in the end of the 3.5mm union to stop it leaking, hoever i forgot to put it back in following the pinion disaster but it has made no difference!
Usefull information i have aquired recently is that the XM pinion will fit directly into the BX rack (the xantia pinion is sufficiently different) and has a 6mm bore opening allowing direct connection fo the xantia feed pipe!

Pressures
soemthing i might as well add FYI while i was first carrying out this conversion (nearly 5 years ago!) i spoke on many occasions and at length the pleiades who pointed out that there is a slight difference in pressure between the pumps (bx =110psi xnatia = 115psi) hoever the difference is very difficult to notice except - this is a possible warning - the first time the rear brakes same significantly into play the rear hydraulic curly pipes exploded, they where old and worn and i had spares in stock, but i guess if the pipes are a little bit past it you might find them failing earlier!

Mostly its a pleasant job, and if your in the mood for a little engineering then its a very interesting job. I intend to put a xantia pump on the D6C when it goes into the car in June this is a difficult task due to intake plenum on the 16v and the fact that i don't have the space usually freed up by the aircon pump!

On the camshaft front, im lost on jeremys points but as the pump is moving to the opposite side of the car the pulley can be taken off. Most of the xantia diesels have a blanking cap over the end of the shaft which you can fit to cover the protrusion, or just leave it to spin!

jeremy · Post by **jeremy** » Wed May 02, 2007 5:40 pm

My point is that its loads of work to get back where you started - ie car doesn't do anything the standard arrangement doesn't - which leads to the question 'If I want to use a 1.9 TD engine - how can I drive the existing pump?' Are the fittings for the ZX airpump the same as the BX pulley - and are they present on all camshafts or do ZX have special ones?

DLM · Post by **DLM** » Wed May 02, 2007 6:07 pm

Vanny - many thanks for your incredibly full and detailed reply. I had some idea of the work needed but can see a number of things I didn't think of. The alleged 6+2 pump for late French 1.9D BXs (engine code D9B) had the following paper specs:

Steering (2- piston section) - flow of 3.7l per min. @ 1500 rpm
Suspension/brakes (6-piston section) - flow of 1.2 l per min @ 1500 rpm

Jeremy - I'm not thinking of the 1.9TD swap, but have always been intrigued since reading the section of the Revue Technique diesel BX manual which suggested that late French BX 1.9Ds had this arrangement, and some of the changes that had been required to implement it. I'd guess it was a testbed for the Xantia layout without the flo-dis. The point of it all is that you eliminate one particular component that doesn't always age well. As with all such things, however, there's a price that must be paid, and I wanted more info on exactly what it'd be.

If I do something in this line, I'll doubtless post on the subject, but can see there's plenty to chew on.

Vanny · Post by **Vanny** » Wed May 02, 2007 10:27 pm

DLM wrote: have always been intrigued since reading the section of the Revue Technique diesel BX manual which suggested that late French BX 1.9Ds had this arrangement, and some of the changes that had been required to implement it.

I'd guess it was a testbed for the Xantia layout without the flo-dis.

The point of it all is that you eliminate one particular component that doesn't always age well. As with all such things, however, there's a price that must be paid, and I wanted more info on exactly what it'd be.

Hmmm, not sure i'd go with that line of thought as the first Xantias had much the same setup as the BX with FD and single output pump. I'd be more along the lines that a BX or more had an under warranty engine change and have simply used a Xantia engine and riggings? Its amazing how you can see one layout under the bonnet that is engineered so well it just has to have been done in the factory, i've been caught out before.

Which component the pump or the FDV? Personally i've actually never had a problem with either (although diagnosed and fixed a few) and i'm personally of the thought that both devices will work almost forever so long as they are properly maintained in this case with regular fresh LHM. I must admit that i probably wouldn't do the conversion again unless i had lots of time and money to enjoy doing it, theres no real gain. That said i do intend to do the job whent he 16v engine goe in but with the intention of adding antisink valves and possibly hydractive and Xantia v6 brakes . . oh i guess i haven't quite learnt my lesson

Oh something else about when and where i did the conversion, i had access to about 15 other BX's most of which where sat waiting to go to scrap so no worries on breaking things and with the option to revert to the standard system if it all went wrong.

Stewart (oily!) · Post by **Stewart (oily!)** » Thu May 03, 2007 9:52 am

I drilled and tapped the end of the original cam and had a BX pulley bored out a little to fit the end, theres no keyway so I used industrial grade TIGHT on the bolt, I also blocked the oilway with a cut off bolt, easiest would be to use a BX cam if you have one.
Stewart

DLM · Post by **DLM** » Thu May 03, 2007 6:10 pm

It's always handy to have a spare BX (or three) around for reference if the driveway space stretches to it.....

As for the flo-dis, I've had a particularly leaky one (leaking from the plugs) on a BX before - they're just a bit of a bind to replace without removing the radiator. Never overhauled one yet. Now I'm about to replace a PR that's weeping away - though that's probably an o-ring problem. I do tend to have experience with BXs that other have "used well" if not too wisely.

Post by **mat_fenwick** » Thu May 03, 2007 6:50 pm

Which would be the best BX cam to use on a 1.9TD engine? Logic says the 1.7TD cam but I have heard a rumour that the 1.9 NA D is the same or similar to a TD 'performance' cam....

Any thoughts?

Stewart (oily!) · Post by **Stewart (oily!)** » Thu May 03, 2007 7:19 pm

I heard the same thing myself, got to be worth a go.
Stewart

tom · Post by **tom** » Thu May 03, 2007 7:48 pm

Just look at the figures in Haynes; The 1.9N/a cam is much more aggressive and will produce more torque.

Vanny · Post by **Vanny** » Fri May 04, 2007 12:04 am

another what i believe to be 'urban myth'.

I've had a 1.9rd cam out of my own departed 19rd sat next to a 1.7td cam out of a pretty much dead engine a number of years ago. The difference was pretty much none!

That said i've also heard the same rumour a number of times and Stefan with the imensly over pressure 1.7td (running 1.9 bar) i believe had the 1.9 cam, still i think i'd want to check them again as i'm not convinced!

DavidRutherford · Post by **DavidRutherford** » Fri May 04, 2007 12:17 am

The figres in haynes are correct, and do show the difference.

Without accurately mesuring the cam lobe shape and height you would never visually see the difference even having a turbo and a non-turbo cam sat next to each other on the bench.

Post by **mat_fenwick** » Fri May 04, 2007 2:58 pm

Sorry to go off at a tangent...but would the 1.9 NAD cam require increased fuelling to notice any real difference when fitted to a TD engine? Or is it simply a 'bolt on' upgrade?
I was thinking of tweaking the boost and fuelling slightly when I do the 1.9TD conversion (still waiting for my Dad's Xantia to give up so I can have the engine!)