BXProject

[Bx Bandit]

Well I don't fancy doing different alts/rads etc so the system will stay as is. As far as the a/c is concerned Doc suggested leaving out the idler roller all together so it's become academic so to speak....

Phil, my Dad's garage was a tinned roof affair and also got very hot!

[mat_the_cat]

I'm about to do exactly the same mod to mine this afternoon, the idler has become rather squeaky. I've got a rough measurement using a length of wire but my plan is to park up outside the factors with an armful of belts, and buy the one that fits best.
I've also noticed that the bushes the compressor mounts onto are a little sloppy, with the result being that it's being pulled out of line. Does anyone know a standard engineering term for them - they are like a top hat in cross section, in rubber with a steel sleeve through the middle?

Update - A 975mm length belt seems to have done the trick, but as mine has the compressor from a TZD Turbo, the sump and spacer from a 16v, and the crank pulley from a Xantia it's probably well different to yours! The principle works though, and doesn't appear to need the extra wrap around given by the tensioner/idler pulley(s).

[docchevron132]

I've also noticed that the bushes the compressor mounts onto are a little sloppy, with the result being that it's being pulled out of line. Does anyone know a standard engineering term for them -

Compressor mounting bushes...

Available from your local main stealer for about £4 a pop.

[mat_the_cat]

Sadly I tried that...after asking for my chassis number he seemed confused when I said that there was no point as the sump came from a 405 (which had smaller holes). Maybe I need to find a new dealer?

[David]

I'm not entirely sure which vehicles had them fitted and if there is any difference between the sumps, but many of the compressor mountings I've dealt with have been "hard" mounted on the sump with top-hat type inserts in the sump lugs ready for the compressor mounting bolts. No rubber in there at all.

Which, given the location of the compressor and the likelyhood of oil soaking, seems a much better arrangement to me.

I don't know if the two types are interchangeable, but if they are it might make a good improvement to keeping your compressor in line.

[Bx Bandit]

/\ Those top hat stylee ones were on the Xanty and the BX. I'm probably wrong here but as they fitted at least two types of compressor mighten the bushes be compressor specific? I doubt it but just a thought like

[David]

/\ Those top hat stylee ones were on the Xanty and the BX.

I've also found them on Xsara, 405 and 406, although they were all 1.9 Turbo-Wiesel models.

Perhaps a difference between petrol and diesel models? I've not seen anywhere near enough petrol models to be able to say for sure.

[mat_the_cat]

That would fit with my (very limited!) experience. The original diesel sump had larger holes, which would be logical with diesels having higher levels of vibration. I had to trim the bushes to fit the replacement 16v sump, and I think that didn't help as any inaccuracies in the trimming would lead to the compressor now sitting slightly out of line.
David, you mention some top hat mountings not having any rubber in them? Do you know what they were made of? They sound like the ones I am thinking of (one pushed in to the sump lugs from each side).
You would think that going along to a dealer with the correct measurements would help, but it would seem he was unable (or unwilling) to search for anything without a chassis number. A Peugeot dealer would probably be my best bet, but that involves an 80 mile round trip...

[David]

The top-hat bushes are turned aluminium I think. Not had a set out for a while, so I might be mis-remembering and they could be turned steel.

I might even have a set, and possibly a diesel aircon sump somewhere. I'll have to have a lookie.

I've had this issue with an XUD engine with Aircon and an alternator only before now, and my fix has been to heavily modify the tensioner bracket from a 405 with PAS and no A/C (pas pump sits where the aircon compressor does) Which means you end up with a fixed alternator (the offset is different between a fixed and a tensionable alternator... get it wrong and belts shred) and a decent tensioner, and a good wrap on all pulleys.

I have photographs somewhere of the modification. It means you have to get a bit serious with a grinder on the cast bracket, but it works really well.

[Vanny]

As far as i am aware, and i've had a look in the sales manual at work, there are only two common types of compressor fitment for european road going vehicles. 'PSA' fitment with ears on the sump, and 'VAG' fitment where the bolts run through the compressor and into the sump. Without looking too closely, all the 'PSA' fitment compressors seem to have the same size hole in them so i guess any fitment difference would be on the engine ears.

David, i'd be very interested in seing the pictures, i'll need to sort something out for the AC on the valver and i'm not convinced about the 'standard' setup.

[docchevron132]

I too have seen all ally and rubberisd bushes, the valver sump I have here is ally top hat, the diesel sump I have has the rubberised bushes, BUT, the compressor I'm fitting to the diesel sump (one day maybe) is a valver unit which bolts to the rubber bushes nay problem..
hmm.. Give us the dimensions of your holes and I'll see if I cant get a set if you like Mat.

Talking of idler rollers... Do I remember seeing somewhere that someone had used an XUD cam belt idler roller to replace the original idler? I seem to recall it bolted straight on existing holes... Although it could be the drugs I guess..

[David]

That was Mr. B, using a diesel tensioner roller on the Aux belt.

And making a bit of a fuckup of it. I'm still fixing the car (granted, I'm not working on it a lot at the moment!)

What he failed to notice was that an adjustable alternator, (as used when you have only an alternator, on a 4pk belt) and a fixed alternator (as used when you have an independent tensioner, with A/C, PAS on 405 with a 5pk belt) have about 5mm difference in their offset. What he had done was to fit a 5-rib crank pulley and a 5-rib A/C pulley, with a tensionable alternator and an idler pulley bolted into the end of the alternator bottom bolt. Given that the alternator was some 5mm nearer the flywheel than it should be, the belt was "twisted to buggery" on the idler pulley, and hence shredded itself, taking the cambelt, and consequently the camshaft and the head with it.

The cambelt tensioner wheel was grinder modified, and bolted to the sump, just to "take up a bit more belt", which worked, but was another bodge as it was also somewhat skew.

Suffice to say that the whole lot was binned, and it now has a fixed alternator, in the correct location, with the modified tensioner from the 405 +PAS -A/C. It all lines up rather well now, although I've had to re-instate the additional roller on the sump, as I couldn't get a belt that was the ideal length for the setup I'd designed. Still, it has even more wrap on the pulleys now!

[Vanny]

That was Mr. B, using a diesel tensioner roller on the Aux belt.

Are you sure Dave fitted that? I thought he bought the car with the AC fitted from 'Bernie', i seem to think it had a 16v condensor instead of a TD condensor on it as well. It didn't look to clever when i first saw it a couple of weeks after Dave got it.

[David]

My understanding is that although he bought the car with A/C installed, he modified and fitted the tensioner wheel to the sump.

I may be doing him a dis-service about the Alternator location though..... Someone cocked up there. Probably not Dave in this case actually...

[docchevron132]

ahh yes, I remember now..
So ideally I'd want to go dind a 19TD 405 and rape everything off that?
Happly 405TD's with air seem to be a good deal more common than BX's...

[David]

Not quite. A 405 with air has an amusing setup with the pas pump above the alternator and a eleventy-billion mile long serpantine belt driving it all. It's a bitch of a setup which isn't particularly clever, and weighs several hundredweight.

What you need for a BX +A/C is a 405 +PAS but -A/C, which has the bracket that then needs about 20 mins of heavy grinding to remove the mountings for the PAS pump, and to allow it to clear the aircon sump. This then mounts your alternator, and gives you the "lollipop" type belt adjuster. (so named, as it's a big roller wheel on a tapering bit of metal, which looks just like a classic lollypop)

Unfortunately, the belt length you then need is a bit longer than the 405 +PAS-AC one, and is in a range of belts that isn't particularly easily available. 1210 rings a bell, but I can't be sure.

405's with air are indeed quite common, and worth 8p these days. I've often wondered about plundering most of it's system for a BX (it's all remarkably similar, right down to the size of the evaporator.)

[mat_the_cat]

As I've mentioned before, this is the arrangement I had:


David correctly identified that it was from a 405, I think one without A/C. This was with the original BX adjustable 5 groove alternator, and extra adjustment with the lower pulley. It all lined up well, but the tensioner and idler pulleys were a bit noisy.
I'm a bit puzzled as to why running the belt just around the crank pulley, alternator and compressor seems to work, yet PSA went to the extra expense of fitting extra pulleys. I wonder whether to ensure no slippage under all conditions, the belt tension has to be higher than is ideal? I've just tightened it by feel, and it seems OK.
Chris, thanks for the offer - if I have no luck I'll let you know.

[David]

Interesting. That looks very similar to the arrangement found on a 405 +PAS +AC, but with some of the added bollocks for the pas pump being up high removed. That's the from-factory bracket for the BX +AC isn't it? If so, it's remarkably rare!

If it is similar, then the bottom roller is a complete waste of time! It barely moves the belt more than about 10mm, and I still can't work out why it was fitted. When I used to run a 405 +PAS +AC I just removed it and binned it.

The 405 +PAS -AC bracket is similar, but not identical. The tensioning is done in a very similar way, but the lollipop adjuster is more upright than on that picture.

[mat_the_cat]

It was from a 405, but whether it was originally from a BX I don't know! (The A/C donor BX was sadly missing the tensioner arrangement). It fitted the 3 bolt holes on the original BX sump fine, and for rigidity I welded up an extension bracket to bolt into one of the M7(!) tapped holes on the block. Nothing was removed from the bracketry.
That worked well on both the BX engine and the replacement Xantia engine. Until I replaced the sump with the 16v unit, and found that only 2 of the holes on the sump lined up, and the one on the block didn't either because of the sump spacer. The temporary 'just put the 2 bolts in for now' job lasted a good 10k miles till I got round to trying a straight belt run.
I was doing the sump swap in the rain on my back, and my mood wasn't improved when I snapped off one of the compressor lugs due to me not noticing the top hat bush had fallen out...fortunately I was able to use the spare lugs by rotating it 90°, but I did swear loudly and continuously when it happened.

[Bx Bandit]

As far as I knew - and this is going from HDU (DR's car with factory a/c) there was a 'swivel' type manually adjustable roller that bolts on the sump and an idler roller that is fitted on the end of the large alternator fixing bolt (normally 21mm and a torx)

like ere:



David, why would the alternator mount bracket for the a/c be different from a normal one