BX Diesel fuel filters

[falling-out-with-my-car]

Hi, I have eloped from the French car forum for a couple of questions relating to BX 1.9TD fuel filters.

I seem to remember my old BX diesel having a sturdy fuel filter with a pressure pump on the top mounted on the drivers side of my engine bay, a nice neat repairable filter unit.

currently (sorry to swear) I have an xantia 1998 1,9TD SX.

I have been running this on 1 micron filtered Waste vegetable oil for about 9 months and have recently fitted a heat exchanger just before the Bosch fuel pump to take some of the strain out of running the car on thicker fuel.
in doing this I have installed some clear fuel line and found that my xantia fuel filter housing sucks in air into the fuel line.

I went to see the citroen dealership yesterday for a seals kit for the filter housing but believe it or not they want me to buy a whole new filter housing @ £67 + vat now I could be in exactly the same position a further 9 months down the road because veg oil eats the seals so I was thinking maybe it would be good to source an old BX diesel filter housing and go from there, they were always a bit more solid state from what I remember. and there is just enough room in front of my LHM tank to make a bracket and retro-fit one to my xantia.

has anyone got any idea please how or where i can source one of these diesel BX fuel filter housings? from what I remember I think they were bosch twist on filters but I'm not posative on that one.

the only other thing that bothers me is wether or not they can cope with fuel flow on a turbo charged engine.

any advice would be gratefully appreciated cheers Nigel.

[docchevron]

Welcome!

There were 2 types of old style filter.
One had a wind on filter, and the other had a canister with a plain filter inside.

Both will easily cope with a TD no problem at all..

Easy enough to find in scrappers I imagine, or I'm sure someone here has one..

Infact if you can hang on for a week or 2 I may well be able to find one laying around up the farm..

[mat_fenwick]

As far as I can remember, all the seals in the thermostat mounted fuel filter are all standard O rings, so any decent engineering suppliers should be able to sort you out with a set. Assuming you have another means of transport once the housing is in bits!

[falling-out-with-my-car]

thanks people,

Ive been to the scrappy today and bought two used xantia filter housings its always hand to dismantle the job first at the scrappy instead of doing it at home and breaking something expensive.

I tried fitting both housings to my xantia but both leak one a little less than the orriginal one so that will stay on the car until I can find a better option, I definately dont like the design of the xantia thermostat mounted filter a standard o-ring and only one bolt through the centre of the fuel bowl to hold the filter housing down against the seal, not exactly solid state and definately not built to last very long out of nasty cheap black plastic.

I am considering going for a clamp together filter with the primer mounted on the top I have found one for a ford 1.8 diesel which is both small and compact to fit in the engine bay and I can do away with the xantia primer bulb to. this one is made of metal and looks pretty well designed .

Thanks for your comments cheers Nigel.

[citronut]

you used to be able to buy a new universal filter head with the primer built into the top for the BX PURFLUX type of unit at a cost of around 40 quid,

but you say the vegetable oil eats the seals so wont it eat the diaphram in the primer on this type of filter head,

regards malcolm

[electrokid]

Could you beef up the o ring with a smear of silicone rubber before assembly - leave it in atmosphere for a short while so it forms a 'skin' ?

[falling-out-with-my-car]

Malcom,

yes I guess it may well eat the seals in any type of primer, what Ive decided to do at the moment is try and fix the old thermostat mounted
fuel filter.

it wasn't so scary as I thought removing it from the thermostat, the seal is well and truly compressed beneath it.

I have ordered a new seal from www.altecweb.com

(point to hardware for o-rings) the new o-ring is 1mm bigger in profile and is made of Viton which is supposed to be extreemly oil and chemical resistant, I'll give this a shot first, if not then it may be the thermostat that regulates the filter housings fuel temperature to stop it getting to hot, this seems to be an unservicable part of the housing.

hence the complete replacement of the whole housing suggested by the citroen spares department. if it come to that I will retro-fit something else.

cheers Nigel.

[citronut]

Nigel

its the diaphram in the primmer i was concerned about failling with the veggy oil, trouble is the primmer is a sealed unit, so nout to repair/replace there either appart from the hole unit,

also i was not aware of a thermostat to stop over heatting of the fuel filter,

regards malcolm

[mat_fenwick]

it may be the thermostat that regulates the filter housings fuel temperature to stop it getting to hot, this seems to be an unservicable part of the housing.

Do you mean the white plunger at the bottom left rear of the housing (when standing at the front of the engine)? If so this allows diesel through the heat exchanger on top of the thermostat and underneath the filter housing below a certain ambient temperature. You can remove this by pulling out the star cup washer, and you can replace the O ring on the plunger.

[Gibbo2286]

Watch out with the Ford filter, the in and out are opposite to the Citroen.
Gibbo

[falling-out-with-my-car]

Matt, thanks for that being as I have my orriginal filter housing out of the cazr at the mo I'll have a go at pulling the plunger on the stat and replacing the o-ring, typical of citroen to tell you its non-serviceable isnt it?

regards Nigel.

[citronut]

i didnt realise that is a stat, i though it were a valve,

the old style head with primmer built into the top i used to by, was a lucas universal, it had an in and an out on both sides, and two screw in banjo blanking caps to plug the two ports you dont use,

regards malcolm

[falling-out-with-my-car]

citro nut you were half right it is a valve but it has a thermostat inside the valve to activate it then it slides across blocking the holes in the base of the fuel bowl to allow cold fuel in to bring down the temperature of the heated fuel so that it does not loose its lubrication properties from overheating, this is all to over complex and half of the silly gadgets on citroens arnt needed with modern fuels.

Ive only found all this lot out in the last two days prodding the french car forum . vegetable oil diesel.co.uk and this site. all great little knowledge bases.
according to many on the veggie sites the seals are all to often eaten by even filtered veg oil so even with good advice I am wondering if it might be more economical to just buy a Lucas/cav cast filter head and pay a little bit more for steel filter cartridges, I have even found a site today that said Lucas/cav steel cartridge filters are the best built filters as other tend to delaminate or fall appart from a reaction with free fatty acids in the vegetable oil.

I found after searching cav filters on fleabay a scotsman selling new filters and housings complete with all fittings for £20 citroen couldn't beat that standing on their heads. the only difference is that they are not heated but on the otherside of the filter housing I have a flat plate heat exchanger so I'm not to worried about the filter running cold.

if you run a heat exchanger like me apparently the pump return line returns enough fuel to raise the tank temperature to 50 degrees C on a long journey anyway so eventually warm fuel will enter the cold fuel filter at some point. I am not to convinced that having a heated filter running veg oil is a good thing because any fats trapped by the filter should stay in the filter not be heated to slip through the filter medium and clog the pump when it cools down.

ther are a couple of people who have absolutely had it trying to stop air ingress with the xud thermostat mounted filters and have gone for the cold filter option being as it is alot easier and cheaper to aquire parts. the washers and o-rings for these lucas/cav filters are made of Vitron which is supposed to be very durable when used with chemicals and oils.

I shall await my ordered new base seals for my orriginal fuel filter and if that doesnt do the trick I'm removing the old thermostat mounted filter housing and retro-fitting a £20 lucas/cav unit with a glass bowel and drain valve. the hard bit is finding a place to install it in an xantia engine bay that has air-con/oil cooling and three radiators.

[citronut]

the LUCAS head i used to buy was a direct replacement/fit for the PURFLUX head, which has the filter eliment inside the aloy canister,

you say the seals are readily availible, but it surely must be detramental to the diaphram which is inside the sealed filter head unit,

which the last time i bought a universal head it was around 40 quid

regards malcolm

[falling-out-with-my-car]

and for that reason I have decided not to buy the filter with a primer pump on the top. didnt you or someone else point this out earlier on?