How to: Refurbish Citroen brake doseur (XM, Xantia, BX and CX)
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- čas přidán 13. 07. 2024
- In this “how to” video I am refurbishing this brake doseur for my XM.
The doseur is basically the same with all hydraulic Citroens from early 80’s to early 00’s when Xantia production ended. That said there is little differences between the models but the seal kit fits to all of them.
Kit that I used: www.cx-basis.de/bremsventil-ue...
0:00 - Intro
0:07 - Disassembly
3:40 - Removal of old seals
4:05 - Installing new seals
5:38 - Rebuild of the doseur
Hi.
Note that most of the problems attributed to the dispenser do not require total disassembly (even if they are all +/- filthy), a lot of dispensers have been replaced for nothing, including at Citroën.
The problems of difficult proportioning, rebounds on the pedal, sudden reactions, braking delay, the rear which falls under light braking (and sometimes which rises sharply when braking is released) or which goes up in the air when braking harder, then falls too low.
All this very frequent is solved most of the time quite simply by a careful purging of the stirrups (and the bottom of the doser in the case of the 2-drawer doser-compensator of the heart of the 80s) see your technical journal for the specific but simple and quite fast.
Leakage problems in the passenger compartment only require changing the rubber mushroom, certainly on most of these cars you need the dispenser in hand to do so.
Proven pressure maintenance problems in one of the 2 brake circuits due to the doser require replacement of the doser. Rare anomaly however.
Internal leaks are normal (up to a point) and replacing the seals of the doser will unfortunately not solve them, the tightness of the drawers is done without seals, excessive wear condemns the device.
Cars that lose rear height +/- quickly when parked must first be serviced: spheres ok, LHM replaced, brakes bled properly. It is essential, on the one hand because There is no good diagnosis without good bases... and on the other hand because we already eliminate quite simply many problems, false problems, which precisely otherwise accuse innocent people devices…pump, dispenser, correctors…exactly as in other fields of mechanics.
A rotten LHM promotes internal leaks.
Please note that there is a Valeo “hydraulic mineral fluid” product on the market, the standard of which is not suitable despite the fact that it is sold and claims to be for Citroen equipment, it is not harmful in the sense that it will not damage installation but it is too thick when cold. So avoid valéo at least under refs 402410 and 402411, to iso L-HV and 6743/4 standards
Double trap… often, it is not expensive!
Valeo with ISO 7308 and PSA B712710 standards, at least under the references 402412 and 403401, is ok (or any other article in another brand corresponding to these standards of course)
Good luck and good road in hydroen.
Thank you for this clarification for the LHM valeo I didn't know.
This perhaps explains why my steering has become harder since I put the LHM valeo on.
But is Mannol 8301 good or not?
I also saw that the RAVENOL LHM + was semi-syntc and also a little smoother than the total LHM +. is it better in semisynct?
I use without problem the mannol 8301 (who is ok with standards ISO 7308 and PSA B712710).
I'm not familiar with Ravenol but it also meets these standards so (regardless of whether it's semi-synthetic), if the price is attractive compared to mannol, I'll probably give it a try when I run out in a few years.
Theoretically, LHM should be replaced every 60,000km or 2 years according to the recommendations of the time (rarely respected), but this was for cars used normally, with annual mileage of at least 10/30000km. On cars that only do a few thousand kilometers a year, that are regularly serviced, that have already had a good tank change, that the LHM remains green and the filters fairly clean after 2/3 years, it's no big deal to keep the LHM for 5 years or more. It's still better than the total lack of maintenance that most of these cars suffered during their initial career.
Thank you very much for this videos. Comprehensive and clear information. 👌🏼
Good stuff, thanks for sharing!
Como poço adequir um jogo de reparação para ,o meu xantia?
😢
Hi! I can’t say for sure since I don’t own a Xantia, but I believe that the kit linked in the discription will fit to Xantia also.
Thanks for this video, great quality and really useful.
Just one question: How did you clean the parts, and mainly the inside? What did you use as cleaning agent?
Thank you! I used mineral spirits but brake cleaner or something similar should be ok. Toothbrush and cotton buds are great help with cleaning and use compressed air if you can.
Мне тоже надо!
Salut.
Mentionnons que la plupart des problèmes attribués au doseur ne nécessitent pas le démontage total (même si il sont tous +/- crasseux ), énormément de doseurs ont été remplacés pour rien, y compris chez Citroën.
Les problèmes de dosage difficile, rebonds à la pédale, réactions brusques, retard au freinage, l’arrière qui tombe au freinage léger (et parfois qui remonte brutalement au lâcher du freinage) ou qui part en l’air au freinage plus fort, puis retombe trop bas.
Tous ceci très fréquent se résout la plupart du temps tout simplement par une purge soignée des étriers (et du fond du doseur dans le cas du doseur-compensateur 2 tiroirs du cœur des années 80) voir votre revue technique pour la procédure spécifique mais simple et assez rapide.
Les problèmes de fuite dans l’habitacle ne nécessitent que de changer le champignon caoutchouc, certes sur la plupart de ces autos il faut le doseur en main pour le faire.
Les problèmes avérés de maintien de pression dans l’un des 2 circuits de frein à cause du doseur nécessite le remplacement du doseur. Anomalie rare cependant.
Les fuites internes sont normales (jusqu’à un certain point) et le remplacement des joints du doseur ne les résoudra malheureusement pas, l’étanchéité des tiroirs se fait sans joint, l’usure exagérée condamne l’appareil.
Les autos qui perdent la hauteur de l’arrière +/- rapidement à en stationnement doivent d’abord être remise à jour d’entretien : sphères ok, LHM remplacés, freins purgés correctement. C’est indispensable , d’une part car Il n’y a pas de bon diagnostic sans bonnes bases … et d’autres part car on élimine déjà tout simplement beaucoup de problèmes, des faux problèmes, qui font justement autrement accuser d’innocents appareils … pompe, doseur, correcteurs… exactement comme dans d’autres domaines de la mécanique.
Un LHM pourri favorise les fuites internes.
Attention dans le commerce il existe un produit valeo « hydraulic minéral fluid » dont la norme ne convient pas pas malgré qu’il soit vendu et se revendique pour les appareillages citroen , il n’est pas nuisible dans le sens où il n’abîmera pas l’installation mais il est trop épais à froid. Evitez donc valéo au moins sous les refs 402410 et 402411 , aux normes iso L-HV et 6743/4
Piège double… souvent, il n’est pas cher !
Le valéo aux normes iso 7308 et PSA B712710 , au moins sous les références 402412 et 403401, est ok (ou tout autre article dans une autre marque correspondant à ces normes bien sur )
Bon courage et bonne route en hydroen.
Gde se gumice mogu naruciti
The link for the kit is in the description. That has all the seals needed.