Pinion valve on a valver

[Kitch]

Right, we reckon this is about the last port of call to finally get the PAS working on the BX. In the last two run outs I drove it on, the PAS did kind of momentarily come back for a few seconds which was encouraging, seeing as it hasn't worked since Dec 2004. I'm fed up of muscle building on my arms and having no PAS ruins the whole feel of the car. Makes it feel heavy, and dimwitted and slow, so I wanna get it ready for when I start using it in a couple of months.

How easy is it to put right though? I'm guessing it's clogged as I'm told by the legendary Doc that the filters in the P.V are the smallest in the system, so they are the first to block up should you hydraflush the system (Which I did!)
I can get an overhaul/seal kit for a Citroen dealer at staff discount (my g/f now works at a Citroen dealer and the discount is very reasonable, so if anyone needs anything....) but is it worth trying to find a complete overhauled valve if they can be had for around £100 or so? If it's only £100 then I'd sooner buy the whole thing, but if they're more like £300 then I'll do the kit.

The other thing is that the tappets in the head need doing, and the exhaust manifold joint needs a new gasket but the bolts are rounded off, so either the head needs to come off or the whole engine either rocked forwards or removed for access. How hard is it to get to the P.V with the engine in situ? You get pretty much nil access down the back of the head in a valver....you can't see the exhaust manifold from the top. It's probably tighter than a TD. Is this an issue or is the job done from below?

Think thats about it for the essay! Cheers

[tim leech]

Regarding the exhaust manifold I need to change mine as its split and blowing merrily, I have a replacement one but as you said access doesnt look easy due the enginesangled backwards, do you need to release the engine mounts and moved the whole thing forward or is it a case of fidding about as is and skinning your knuckles.

[DavidRutherford]

Regarding the exhaust manifold I need to change mine as its split and blowing merrily

How on earth did this car pass an MOT?

I know on the TD models you can remove the top engine mounting and pull the engine forward a bit, but the access doesn't improve that much, and it does make the engine become a bit wobbly. Access to the back of the head from underneath isn't too bad but if you're working on axle stands, that's a lot of working on your back.

Regarding the pinion valve, bear in mind that the Pug 405 pinion valve is identical, (as is the whole rack) so if the part for the BX is overly expensive, then a used 405 one may be an alternative. As the 405 PAS system is closed (IE it's PAS and nothing else) the pinion valves don't ever go wrong or bung up. All you would need is a seal kit.

As another alternative, I've got a couple of decent BX power racks that could be swapped as an assembly.

[tim leech]

Its the divider inside the manifold itself thats split open, so the exhaust doesnt actualy leak but sounds like it blows through the whole in the middle, when its cold its worse, but quietens down as its gtes hot. Weve had the downpipe off and welded the divider up but it didnt last, I have a new one to go that it "split free"

[rob-bx16v]

kitch,

i have just recently had mine done. I bought an overhauled pinion valve from pleiades for £78 + vat which it came to about £88 i think? they also do next day delivery for about a tenner. They normaly charge about £60 surcharge but they said they had plenty in stock and didnt charge me the surcharge but asked me to send the old unit back

pleiades number is 01487 831239

hope that helps

[Kitch]

Tim - removing the manifold with the engine in place will be a prick of a job! I took mine off when I did the rebuilt when the engine was out....nice and easy. But due to the access of some of the bolts, doing it in place would be a nightmare! I reckon it could be done, but with plenty of patience, someone under the car guiding you and more flexi-drives for ratchets than you can lay your hands on!
I know what you mean about the blowing too. I think mines doing the same. There are no leaks at all, but it sounds like it is. Might look into fitting my spare manifold and buying a genuine centre section as apparently they actually are better than the replacement items (for once!)

David - interesting to know, I didn't realise 405's were the same. Could be fairly easy to track one down in those as there are plenty at the local scrappers. But if brand new are only £88 or so according to Rob, then it's perhaps false economy buying used?
May well be very interested in a rack though. In your opinion, would it be easier overall to change? I'm guessing you just unbolt and unattach it from everything and slide it out from one side, rather than trying to change a valve hidden down the back of the engine?
I guess my current rack can't be in too great a shape as it's been strained for about 3 years!

Rob - very helpful that, cheers. Was it an arsehole to change?

[tim leech]

I have a good used exhaust manifold and a nearly new downpipe with divider (thanks Mike P) which my car doesnt currently have so thats a job for the better weather.

If I manage to get the manifold off I will let you know, if I can do it then anyone can lol

[docchevron]

It's a good deal easier to change the pinion valve than the whole rack, they are a bit fiddly, although life is much easier if you drop the back end of the subframe a bit.

I seem to remember Plaiedes did rebuilt pinions for not alot, but be aware there are two different types.

As for the exhaust manifold, if you remove the top engine mount and swing the engine forward (easier with the inlet manifold removed) then you can get to the top nuts without too much hassle, the bottom nuts are easy enough from under the car, just a bit fiddly again.

If the tappets need doing anyway, it might be worth pulling the head and re-seating the valves, checking the guides and replacing the valve stem seals whilst your at it?

[rob-bx16v]

kitch,

i didnt do the job myself as im not very confident but my mechanic had it done in an hour.

[AlanS]

I wouldn't get too excited about the 405 and BX having identical pinion assemblies.
They look the same at first glance but I discovered a couple of years ago when I had one out of a 405 and a mate had one out of a BX he said I could have, that the problem/difference is that the BX one has a return line for LHM which the 405 doesn't have, so unless things have changed, (Doc mentions 2 types) I'd suggest looking at it very closely before you instal or you might find you have a return line "left over."
Getting to the F/D is fun, but providing your car doesn't have air/con, I'd suggest that the removal of the radiator is possibly the best option. If you have air/con, it is still possible to swing the condenser away on its flexible hoses.
Exhaust............what a PITA they are to get to.
My common practice is to support the engine on an engine crane, remove top mount and bottom and take radiator out as a precaution.
Lower or raise engine then as is required. Oiling the threads on teh flange bolts for a few days prior to doing the job can help (oil not WD40 BTW) and often a pair of pointy nosed vice grips will hold the bolt long enough for the nut to loosen. If not, an angle grinder or saw are the only options.
To get access to the manifold bolts, try getting a couple of long extensions for a 3/8" socket set and use only an 8 sided socket. A uni or knuckle joint on the extension is also a handy addition.
Access can be got in a sort of a fashion from below, but again, with the engine suspended on a crane it makes it so much easier to get to.
Tappets are as pointed out of the non adjustable hydraulic variety and if clattery, chances are they need removing, cleaning, burping, re-oiling and refitting making certain they are returned to the holes from whence they came.
I have also heard tappety noises from these engines when the cambelt has stretched or been incorrectly installed and has too much slack between the two cam sprockets, so may pay to check that before embarking on a head off job.



Alan S

[Kitch]

Ah so we're probably looking at a pinion valve job then? Might be worth finding out which type I've got and ringing Plaiedes.
The tappets do need doing, but I seated the valves and changed the seals last time I did it.
Problem now is that either the oil surge caused them to gum up and now they're noisy, or that I ballsed them up and put back in different places. I'm familiar with the overhaul of the buckets, but surely once you've stripped and rebuilt them, theres no reason why they have to go back in exactly as they came out, as they've been 'reset'?

[Vanny]

think i've done this job just about every direction possible now, with the engine in and the long drive shaft out, it took me about an hour to change the pinion lying on my back. Tricks to remember are that you will save MANY hours of labour if you have a spanner moneky to go fetch, and you really can do the job in an hour if you have a spare pinion with the seals already changed.

Most fiddly bit of the whole operation is removing the heat shield! Oh and start by disconnectection the break away joint on the steering shaft INSIDE the car, you can save a lot of time by doing this first!

I do have a load of pictures of the job being done and a part completed total step by step guide if its of use?

DONT follow the haynes as it lies in multiple places (like un bolting the sodding rack!)
DONT try to align the pinion, its not needed by its design.

[AlanS]

Ah so we're probably looking at a pinion valve job then? Might be worth finding out which type I've got and ringing Plaiedes.
The tappets do need doing, but I seated the valves and changed the seals last time I did it.
Problem now is that either the oil surge caused them to gum up and now they're noisy, or that I ballsed them up and put back in different places. I'm familiar with the overhaul of the buckets, but surely once you've stripped and rebuilt them, theres no reason why they have to go back in exactly as they came out, as they've been 'reset'?

It's not the resetting that's the problem.
I've found variations in outside diameter also.
I read a posting the other day regarding rattling tappets on an Mi16 where a guy who is a dealer reckons you need to run stuff in the engine.

Here's his post.

I have never had cause to replace an Mi16 hydraulic valve lifter yet.... Despite having encountered some with 'sticky' lifters..... here is what I ALWAYS do before condemning a lifter:

* Run engine to operating temperature, then pour a can of Wynns (or similar) valve lifter cleaner, into the engine, run the engine ,stationary, at about 4000rpm until the noisy lifter goes quiet.

Reason why most hydraulic lifters get 'noisy' is because they 'gum-up' with varnish and carbon deposits, often restricting the oil hole, which allows oil pressure to 'pump-up' the lifter. So a good strong solvent, will often remove the varnish and carbon and return the lifter to good working order..

Might save a few hours work.


Alan S

[docchevron]

Indeedy, the tappets wear a bit, as does the head, so they kinda machine themselves in operation.
If you put the tappets back in the wrong holes, they can be a bit tight / loose / not very good.

If you're replacing with a set from another head, or new ones I find it best to run "running in oil" in it for 500 miles or so, it helps everything find it's own nieche.

A rebuild kit for the pinion may be the best option, when I did the one in the TD I had the car in bits and didn't realise till it was out that the shiney new one was wrong, very wrong. Oh how annoyed I was...
Handily, I had a complete rack with a good pinion of the correct variety in the back garden (who needs plants?), so I popped that in!

[Geoffrey Gould]

Yep it was me that b+gg+red up that little job, bought a pinion (new) boxed and labeled BX and it should have been OK but the number / size of the teeth were very different so please be careful, Doc was not happy, I think the only reason I'm still here is that I'm his dad and so lived to tell the story.
Sorry DOC.
Cheers.
Geoff.

PS difference between power and non power assistance???