BX gearbox & bleed nips

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Rob Marshall
Posts: 127
Joined: 02 Oct 2003, 22:40

BX gearbox & bleed nips

Post by Rob Marshall » 13 Aug 2004, 17:20

My TD BX is leaking g/box oil from the filler plug. It is a 1992 car with reverse under 5th. The change hasn't been v.good since the garage changed the gearbox oil 18 months ago, using EP80/90.
Have got some semi synthetic 'box oil which is EP75/80 & I want to do a complete oil change.
Have approached the local Citroen dealer, who want chassis number, inside leg measurements etc.
I presume all I need is:
1. Drain plug washer.
2. Filler plug washer.
Also:
3. 2x bleed nipples for rear calipers. (Mine are a bit dog eared & need changing)
Are all these parts the same as a TD Xantia???
Also, is the drain plug at the end of the small housing on the box which can be seen pearing under just behind the passenger side front wheel?
Rob

alan s
RIP 2010
Posts: 2542
Joined: 26 Jan 2001, 16:53
x 5

BX gearbox & bleed nips

Post by alan s » 13 Aug 2004, 18:56

The drain plug on a BX points towards the rear of the car and is (from memory) 19MM <b>under no circumstances remove the 16mm bolt that is on the bottom of the transmission!!</b> That holds the recverse idler in position and can create a major gearbox strip down if removed.[:0]
If you use a EP80/90 oil, you will have problems with gearchanges, this is an historical fact.
I hope the semi synth EP75/80 will be OK as there have been some pretty ordinary reports of BXs when they have synthetic put in the gearboxes.
The best results I have had personally has been using a straight 80 grade mineral oil with Nulon G70 additive in it; leave for a couple of thousand, drain again and refill with the same mix including the Nulon.
They usually take 2 litres for a full drain/refill & I usually fill via the passengers side via the level plug.
Alan S

tomsheppard
Posts: 1801
Joined: 19 Dec 2002, 15:46

BX gearbox & bleed nips

Post by tomsheppard » 13 Aug 2004, 18:57

Rob, go very careful with the bleed nipples. Wirebrush them thoroughly and anoint them with Diesel for three weeks before attempting removal with a six sided socket. Have drill, tap and oversized nipple ready to circumvent Sod's Law.

Rob Marshall
Posts: 127
Joined: 02 Oct 2003, 22:40

BX gearbox & bleed nips

Post by Rob Marshall » 13 Aug 2004, 19:03

With my nipples: They are 8mm, and were a bit motheaten, but enough of me, what about the car... (groan!)
Changed the LHM with rinsing solution and managed to loosen them OK. I removed them, applied copper grease to the threads, and tightened with mole grips (not super tight though!) After 3,000 miles I have to replace the rinsing stuff with LHM, and plan to replace the nipples to save me any future grief. So yes, they are not seized it, but I have ordered a replacement set to save future problems.
With the dreaded 16mm bolt that I should NOT remove, where abouts on the bottom of the transmission does that live? It is not the end housing, near the filler plug??
ROB

Stuart McB
Posts: 1635
Joined: 03 Oct 2003, 00:50

BX gearbox & bleed nips

Post by Stuart McB » 13 Aug 2004, 20:48

Sorry EP 80/90 in you BX gear box? That sort of stuff is great for industrial and 4x4 gear boxes and back axles. But I wouldn't put it in a standard saloon car. As for the nipples,I have found that holding ones breath as you undo then makes no difference at all. Breath normaly, this aides cursing when they do go wrong and also aide congratulations when they go right.

alan s
RIP 2010
Posts: 2542
Joined: 26 Jan 2001, 16:53
x 5

BX gearbox & bleed nips

Post by alan s » 14 Aug 2004, 06:03

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Rob Marshall</i>


With the dreaded 16mm bolt that I should NOT remove, where abouts on the bottom of the transmission does that live? It is not the end housing, near the filler plug??
ROB
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Rob,
With the drain plug, the best I can suggest is to lie down besides the passengers side and slide your arm behind the front wheel and head towards the front of the crossmember. You'll see just showing, attached to what is basically the final drive or diff, a bolt that would take a 19mm socket or alternatively can be loosened & tightened using an 8mm square key, the hole for which is located in the middle of the 19mm hex head. It points towards the rear of the car.
Rather than try to describe exactly where the 16mm one is, let's just say don't touch anything that points downwards and takes a 16mm socket. If you have taken it out, you'll find it's a weird looking thing as it has a thread just below the head as one would expect, but then a section of plain unthreaded steel rod. If you have accidentally taken it out, under NO CIRCUMSTANCES start the engine, play with teh gear lever or try to put it in gear. Just carefully & gently slide it back into position and tighten it up and then make sure you still have gears before proceeding on with teh gearbox oil change...........that's what I did the first time I changed the gear oil in a BX anyway; I was lucky, I got away with it [:0][:(!][:(!][;)]
Without setting off a debate on pros & cons of additives, can I say that whilst I won't touch engine oil additives with a barge pole, I have had real success with the gearbox stuff, in particular Nulon G-70 which I have been told by others over there you guys can get.
If the system of a couple of changes at say 6 - 12 month interval is used as I suggest, the difference is even more unbelieveable. That's not just from me, but from a couple of other BX owners who have also tried it.
Alan S

tomsheppard
Posts: 1801
Joined: 19 Dec 2002, 15:46

BX gearbox & bleed nips

Post by tomsheppard » 14 Aug 2004, 23:39

Yep, and I swear by Molyslip which seems to improve change quality dramatically.