Setting Ignition Timing On Cars Manufactured After June 1971

On an internet forum there has been a very long and protracted discussion about helping a fellow DS owner trouble shoot problems setting up the timing on his car. He happened to be fitting 123 electronic ignition, but the big debate wasn't really 123 specific. It concerned the underlying instructions for 'pre-setting the static timing' on Ds manufactured after July 1971.

In Citroen's 'manual 814' and it's French equivalent 583, the instructions for setting the timing are essentially these:

• Use the notch in the flywheel to find the static timing position
• Mark this as 'position zero' on your timing gauge.
• Set the distributor up to cause an ignition spark at that point
• Run the engine
• Set/ adjust ignition advance (move the ignition point) for the particular engine.

In essence, Citroen provide these same instructions for cars built before July 1971 and for cars built after July 1971. What's the significance of that date? 

• For Ds built before July 1971, the notch in the flywheel  - used to pre-set the static timing - gave 12 degrees before top dead centre for number one cylinder - 12BTDC. This is established and proven to be an adequate static timing point for completing the rest of the timing set-up process
• After July 1971 the piston of the notch was moved. it now gave top dead centre for number one cylinder - TDC. 

Notch in the flywheel

Regardless, the Citroen instructions for ignition timing are essentially the same. 

Citroen timing instructions for pre-July 1971 engines and.......

......Citroen timing instructions for post-July 1971 engines.

In both cases the instruction is to use the point given by the flywheel notch, as the point at which to set up the initial distributor ignition - the static timing.

The upshot of this is that for post July 1971 cars, because you start at TDC, when you set the static timing, initial spark ignition would take place slightly later - when the engine was at TDC. And combustion would occur when the piston was well into its down stroke. And when setting the advance, you would expect to need to move the distributor and ignition point more (degrees) to reach the same ultimate timing position than you would for pre July 1971 cars.

Well that's theory.....even though the intended process of setting the advance would ultimately leave the engine with the correct degree of timing, the problem and debate on the forum concerned practice: whether or not beginning the process at TDC is a viable start point. The recent debate on the forum concerned the wisdom of running an engine with ignition happening this late, whether it might cause engine damage and whether the engine would run at all. If you can't get the engine going, you can't set the advance......

The general consensus was that - for Ds built after July 1971 - following the Citroen workshop manual and starting the timing setting process from a 'static timing position' of TDC was simply not viable. Citroen were lambasted, and  - for the DS owner being helped - the 123 manufacturers were pilloried for not correcting Citroen's mistake.

Worried and confused? So how can you tell what flywheel is in your car? How do you set the timing on a DS manufactured after July 1971?

Worried

Don't be.

Confused

Read on.

Does Your Flywheel Notch Give 12 degrees TDC?

If you are not sure what flywheel your car has - or simply want to check - you can go about it this way:

• Remove the spark plugs and slowly crank the engine (or if a five speed, jack up a front wheel and turn that).
• Identify the beginning of the compression stroke of number 1 piston using a balloon or similar.

Balloon deflated - engine not at compression stroke

Party time! Compression stroke found!

• Stop just as the balloon begins to inflate. Remove the balloon and slip a long dowel or screwdriver into cylinder number 1 as a 'tell'.

Using a marked dowel as a 'tell' to find TDC
(The white cap is only there to centre the dowel)

• Insert a 6mm pin (a drill bit is ideal) into the timing hole under the alternator.
• Continue to slowly turn the engine until the drill drops into the notch in the flywheel and 'locks' the engine. (You should also have noticed the dowel/ screwdriver rising as the piston continues up on its compression stroke - until the point the flywheel locked.)
• REMOVE THE DRILL.
• This is the crucial bit: continue to turn the engine slowly and, at the same time, observe the dowel/ screwdriver sticking out of the top of cylinder one.

Case 1: If the dowel/ screwdriver continues to rise for a while before beginning to descend, then the point at which the drill engaged with the flywheel was BEFORE top dead centre (aka 'TDC'). For carburettor DS cars built before July/ August 1971, the expectation is that you will find 'case 1'. On these cars the point at which the drill drops into the hole beneath the alternator (the timing point) gives 12 degrees before top dead centre (the firing point). The timing point and the firing point are the same.

For this 'case 1' scenario, I covered the process for setting up the static timing with a mechanical distributor HERE and HERE, and for fitting a 123 electronic distributor - including setting the advance - HERE.

Case 2: If the dowel/ screwdriver immediately begins to descend, then the piston is also descending and the point at which the drill engaged with the flywheel was already AT top dead centre. 

From July/ August 1971 onwards, the expectation is that you will find your car/ engine meets 'case 2' above. On these cars the point at which the drill drops into the hole beneath the alternator (the timing point) gives zero degrees before top dead centre - TDC. So how do you set the timing??

How To Set The Ignition Timing Where the Static Timing Position Gives TDC

The general consensus was that a static timing position of TDC cannot be used to set the static timing. The position of the crank and piston needed to be altered before the static timing could be set. In essence a slightly earlier static timing point needed to be found and used. Some people say the engine needs to be "wound back" but in reality this means "winding it forward" again.

This would seem to be a good way to go about things......

• As above, find the intended statistic timing position using a 6mm pin. This needs to be using number one cylinder and when the piston is on its compression stroke.
• Slowly rotate the engine to cause the 6mm pin to drop into the timing slot of the flywheel. (For these engines/ flywheels this is of course TDC).
• Put a thin white mark on the flywheel opposite the 'zero' of your timing gauge.

White mark opposite the zero

• REMOVE THE 6MM PIN
• Rotate the engine again until you again find the start of the compression stroke for number one cylinder again. 
• Now slowly continue to rotate the engine until the temporary mark you made is opposite the '6'  mark on the gauge.

You might find the engine over-rotates and your mark goes past the '6'. if so, repeat the exercise  until you successfully stop the mark opposite the '6'. 

• Without disturbing the engine any further, set up your distributor to cause ignition to happen at this point.

For an  old mechanical dizzy, this is the process of using a test lamp to indicate and so set the precise point at which the contact breakers open.

And if you are fitting 123 ignition, this is the point at which the little green LED light comes on.

• having found this point, clamp the distributor up just so that it can only be turned stiffly.

What have you just done? Even though the notch in your flywheel finds the TDC point, and your white mark on the pulley indicates TDC, you have set your 'static timing position' when the engine was 12 (crankshaft) degrees before TDC. As such, you have mimicked the process for cars manufactured before July 1971 and should be confident that the engine will run sufficiently for you to complete the timing process - setting the advance.

Setting The Engine Advance

If you have followed the steps above, the key point to bear in mind here is that while you have set up your distributor to trigger ignition at 12 degrees before TDC, the mark you have made on your pulley equates to zero degrees of advance. So when setting the advance, you need to see the full amount of advance on your timing gauge. You don't need to do any column 'C' maths to account for the 12 degrees as would otherwise have to do for a pre July 1971 car. Follow column 'B' in Citroen's timing values table. But do remember to halve the value....

Here is an example. This is an extract from Citroen's table of timing values.

Illustrative extract from Citroen's timing table - manual 814

Using a 2347cc DS23 of the 1973 year as our example, (second row here) the table says that the advance timing should be carried out at 2000rpm and the total advance should be 23 crankshaft degrees. That's a total of 23 degrees. Note that column 'C' is empty. The assumption for your DS 23 is that, when setting the advance, you need to set all 23 degrees, because you have been instructed to start with TDC as your static timing point - your 'static setting' as column 'C' calls it is zero.

If you had a DS23 covered by that timing curve and those values, and if you had followed the process I've described here, that is what you would need to do when setting the advance: you would be looking to see 23 degrees. Since you would be using the pulley to set this, you would be wanting to see the mark you made move by half that value '11' 30"

Note also for the first row above (a particular 1985cc 'DV' vehicle) that column 'C' is populated. Why is this? Well that row covers certain vehicles/ engines used both sides of the fateful July 1971 change in flywheels.

• For vehicles in this row but before that date, the static timing position and the white mark made on the pulley already gives 12 degrees. So of the total 24 degree specified, only another 12 remain to be set in the 'advance' process. 12 degrees of crankshaft movement are measured on the pulley as 6 degrees of movement against the gauge: from zero to 6. That's what column 'C' is telling you.
• For vehicles made after July 1971, the assumption again is that you are starting from a zero degree position and will need to set all 24 degrees - just the column 'B' figure.

That's just about the key difference when setting up the timing on post July 1971 cars. Any error in the process is not the fault of 123 ignition per se though the instructions that came with my car were pretty cryptic. It's the Citroen factory workshop manuals that say to start the process from TDC, and fail to suggest that the engine should be/ needs to be 'wound back'. 

FOOTNOTE

Someone has recently sent me PDF (so presumably downloadable) instructions for fitting 123 that are specific to the DS and which do mention the need to 'wind the engine back' 12 degrees before you fit the 123 distributor and rotate it to light the little green LED.

Extract from 123 electronic ignition PDF instructions for Ds

I've also re-read the cryptic generic instructions that came with my 123 and I think that the process outlined would be sufficient for setting the static timing on a DS made after July 1971. The instructions would work.

Generic and cryptic - 123 ignition instructions

Here is what they say in essence:

• Using the distributor cap as the guide, put a mark on the perimeter of your old distributor body that aligns to the 'cylinder 1' HT contact of the distributor cap when it's fitted.
• With the distributor cap removed, crank the engine so that the rotor arm points to the mark you have just made - the point where the rotor arm would cause a spark to number one HT lead if the distributor cap was fired. 
• Leave the engine in this position and replace your old distributor with the 123 distributor
• Twist the 123 distributor anti-clockwise until the little LED light comes on.

What the above process essentially does, is it use the position of the distributor about to be replaced, to find the current timing position of the engine and use that as the static timing position. And because it uses the distributor cap HT lead position for cylinder 1 as the reference point for the mark, when the rotor point to that mark, cylinder 1 must be on it it's compression stroke. So using the position of the rotor against the mark made on the distributor perimeter, is a rough equivalent of rotating the engine so that any mark on the pulley aligns with '6' on the gauge - about 12 degrees before TDC. As such, it should be enough for static timing.

The caveat to this is that the instructions assume the engine hasn't been cranked or otherwise rotated with the distributor out. They rely on the distributor being in the same rotational position as when the engine was last running. That isn't mentioned, but the generic 123 instructions are written from the point of view of swapping out an old distributor - so perhaps that omission is understandable.

Refitting the Rubber Door Seals

This is one of the jobs that - for me - transforms the hard metal chassis into a car. For that reason I was  looking forward to it, but at the same time was also dreading it. it's a tricky little job that doesn't easily forgive mistakes. And I only wanted to do it once.

Door seals refitted

The rubber door seals go around the door frames. The doors - and their glass - close against these seals. The seals fit into metal channels around the door frame edges. 

Metal channels are parts 11 and 14. Door seal rubber is part 15

The channels are used to crimp the seals in place. Fitting the seals is all about the channels. The channels, the channels, the channels......

The original channels were made of quite thin metal. That made them easy to close up when fitting the rubber seals. Unfortunately being thin also made them prone to rust - and to them needing replacing. 

Water wicks up and rusts the channels

And that meant you need to take the rubber seals out. Removing the seals when carrying out restoration is easy and satisfying: tugging on the rubber at an angle opens up the crimped edge claws and out they came.

The rubber seals survived this treatment well. The trouble was that the channel crimping claws  - being only thin metal - opened-up and became badly mis-shapen and wobbly along their length. You can see that in both the photos below.

As such, putting the seals back on then became a lot harder......Some restorers replace the whole crimping channel with modern reproductions. 

Reproduction channels are available. They are 'handed' so be careful what you buy

This might be because the old, thin channels have become very rusted but might also be because - having removed the rubber seals - they can see the damage that's been caused to the claws of the old channels. We should be grateful that reproductions are available, but I'm told they are not a good fit around the curves of the door frame and require a lot of fettling.  And being pressed into a 'W' profile - they are not easy to reshape!

Reproduction channels

Curve is not quite right.....

The other problems with the reproductions are that:

• They`re made of thicker metal. They are less easy to close up once the door seals are fitted and there is the risk of damaging new chassis paintwork when you attempt to do so.
• The crimp arm and claw is a bit too big. It doesn't fit the shape of the inner door trim.

That's why I disturbed the seals as little as I felt I needed to......

Seal only partly detached and tied up out of the way

.....and used as little replacement channel as possible.

I used as little new channel as I could get away with

Old channel being removed

Patch section of new channel welded in

It's also why - when I thought about painting the chassis - I was keen to avoid removing the seals. Originally, after fitting the new outer sills, I seriously thought about re-seating the rubber seals in their channels and then - somehow - masking off those areas for when it came to painting the chassis. 

More recently, as I stripped old paint from the chassis, I realised how ridiculous that was. Also -  when I was working on the outer sills - I'd caught the rubber seals with my angle grinder leaving some ugly nicks and scars......

Telltale damage from an angle grinder

......and my ego made me keen to replace those door seals with unmarked ones. So.....even knowing the damage it would do to the crimp claws, I had carefully pulled all four seals completely off. 

Now I've gone and done it......

It isn't really viable to try and open up the crimps to remove the seals as you still end up with wobbly claw edges.

Because of the damage this inevitably caused to the channel claws, as part of the preparation for chassis painting, I invested a disproportionate amount of time in re-shaping the claws on the channels. More specifically, I spent the time on restoring the 90 degree angle to the crimping arms and claws and making the channel arms straight and consistent as I could over their lengths. To help me, I made a couple of tools to fit inside the crimp claw.

Home made dolly to re-shape the channel claw edges

Smaller tool for tight work

The idea being that these acted as 'dollies' on the back of the claw and I used a hammer to reshape the metal and restore the 90 degree angle to the claw as best I could. 

I used the tool to re-shape the claw angles

These tools worked surprisingly well but it still took me a good couple of days to work all around the four doors - inside and out - straightening out the claws of the channels.

Fitting the seals is a bit of an art. The metal channels have what I and going to call a 'W' profile. You need to use your imagination a bit.

'W' profile of seal holding channel

The big black rubber seals need to fit into both of the valleys of the 'W'. Note that the two arms of the 'W' have small 90 degree 'claws' folded inwards. It's these claws that crimp the seals in place. 

On the door seal, the edges of the seal fringes that get crimped in have fattened lips to help hold the seal behind the crimp claws.

Fattened lip on the edge of the seal fringe

When crimping, the idea is to close up the arms of the 'W' so that the claws fold over the top of the seal lip.

Arms and claws closed

If the crimp claw is mis-shaped - and especially if it is squashed flat or closed - the seal edge will not/ cannot locate behind it. The seal will sit proud (not straight) and/ or will start to lift out of the channel at that point.

To make it more interesting, on the insides of the door frame verticals is additional trim. In my case it's white ribbed piping trim. I think later cars had black?

Door piping trim inside the cabin

The trim has an 'L' shaped groove along it and hooked edge.

Groove and hook of the inner trim

This piping fits over the inner claw of the channel 

Now. Whereas on the outside of the car, the claw crimps directly to the black rubber seal.....

.....on the inside of the car you crimp the white trim against the door seal to hold both pieces of trim in place. 

Again, if the claw edge of the channel is mis-shaped it affects the fit of the white trim and that - in turn - can affect the fit of the door seal. You can see in the photo above that the fattened edge of the door seal is designed to fit in behind the round profile of the white trim. If the claw of the 'W' channel is mis-shaped, that will be difficult.

By the way, notice how - in my demo photos using reproduction channel - the white ribbed trim doesn't properly fit on the channel. It's not the groove in the trim that's wrong - it's the reproduction channel that's a bit too big. The trim can't properly roll around the 90 degree claw, meaning the white trim doesn't sit as intended. It hangs fairly loose and doesn't leave the intended space behind it for the fattened lip of the seal. It can make it harder to locate the seal behind the trim - because it's free to moves and takes up the seal space - and since the white trim is meant to be holding the door seal in place, there is a risk they both work loose. As I had retained the original channeling, then unlike in the photo above, my white trim fitted well to the lip and arm of the 'W' which made assembly less fraught.

You are also perhaps realising that, on the inside of the doors, the seal and internal trim need to be fitted at the same time - before you crimp. And it's the same for the black finishing strip over the tops of the doors and down the front 'A' posts

Internal black trim over the 'B' pillar

That needs to be fitted at the same time as the rubber door seals. And as a bonus, that black horizontal trim has a foam bead tucked inside it making it a little more awkward to manipulate. All in all it makes fitting the door seals a bit fiddly to say the least. Even harder if your roof is still on the car!

This is how I went about it

My black rubber seals had silver paint on them from some poor quality car re-spray in the past, and some kind of mastic along the crimping edges. Cellulose thinner helped to remove the silver paint and picking away until I was close too tears and my fingers were raw was sufficient for removing that f**king mastic.....What I was left with was REALLY loved quality rubber: very, very supple. Good as new. 

With door seals ready, the channel edge claws re-shaped and the chassis now painted, I put a thin bead of 'CT-1' sealant in the outer valley of the 'W' channel. The idea was that this would fill-out the channel after the seal was crimped and prevent moisture wicking up and causing unseen rust. That's the idea anyway....

Fitting the seals is tricky because each rubber seal is surprisingly heavy. And flexible. And long. The job is made harder by gravity - with the door seals sagging and twisting like a snake. Even worse if it drooped after fitting in the groove filled with 'CT-1' as the sealant went everywhere.

My roof is off my car, so I could access the roof rail. Readying some lengths of masking tape, I roughly positioned the seal along the top edge of the door frame - and then loosely taped it in place. I then took time to align the top fringe edge of the seal with the top of the doorframe and particularly its corners. they were my reference points for the rest of the refit. I carefully positioned the fattened lip of the rubber seal....

Fattened lip on the outer fringe of the seal

.....under the channel claws in the two top corners of the frame and 'tacked' the seal in place by lightly closing the outside claw at strategic points. This was the point at which I'd wish I could have grown another pair of arms and hands. Then - without stretching the seal, I worked my way around the outside perimeter and down, just lightly closing the claw edge as I went. Just enough to hold the rubber seal in place.  I reviewed the fit as i went - just to make sure the seal remained fitted as it should. 

The 'S' bends at the top line of the door were particularly hard to do. Even though the rubber is moulded to shape, if the claw of the channel is not adequately re-shaped here so that it grips the seal, the seal will pull itself out and will not follow the intended line.It's also hard to evenly crimp the lip in this area. 

Once I was happy that the seal was sufficiently held in the outer claw, I moved to the inside of the door. I 'rolled' the white ribbed trim onto the claw of the channel. 

You need to 'roll' the trim onto the claw edge

This is why that claw edge needs to be straight or straightened out. If it's not, the trim simply won't fit. And if it isn't fully engaged on the claw - then the ribbing of the trim will accentuate any bumps and uneven fitting. It will look awful.

The top of the inner door frames similarly have a black finishing strip. But it's one long strip on each side of the car that goes from the back of the car, right across the tops of both doors, along to the front edge of the from door and down to the sill. That also needs to be rolled on to the claws of the door frames before you locate the seal.

When the vertical and lateral trims were both located on the claw edges, I then pushed the loose fattened lip of the rubber seal.....

Fattened lip on the inside fringe of the seal

.....in behind the trim. 

The seal should fit behind the white trim

I then made the crimp, closing that half of the 'W' channel together using a rubber coated 'dead hammer' applying light, even, taps along the length of the trim. I took my time to close the crimp gradually.

The inner fringe of the seal  was now properly fitted to the inner face of the door frame. However this has the effect of stretching the seal over the middle hump of the 'W' and pulling the outer lip out of place again.......

So, turning my attention back to the outside of the door frame, I checked that the lip of the outer edge of the seal was still engaged behind the claw and worked my way around the perimeter, re-seating the seal as necessary and now fully closing the crimp edge. To do this, I used a hammer and another special tool.....

I used a wide, thin piece of wood as a drift

Forcing a fatter tool in the gap between the chassis and the seal would have added to the forces already pulling seal lip out of the claw  - at the exact point and moment that I was trying to closing the crimp. Whereas I could locate my thin piece of wood in the gap without disturbing the seal. 

Using a thin piece of wood as a drift to close the crimp

Wood was also softer and kinder on the paintwork and being a wide piece of wood, the load from any hammer taps was spread over a longer section of the channel arm - meaning it created a neater, more even crimp. I used a narrower tool to work around the 'S' bend in the channel at the top door edges.

Similar tool for the 'S' bends

When I was happy with the fit - and that the seals were not going to pull themselves out, I wiped off any excess CT-1 and left things to settle. While i was fitting, the CT-1 worked as a lubricant - sometimes helping me locate the seal but at others helping it pop out. Once the CT-1 cured, it helped 'cement' the seals in place.

I did that for all four doors of course... It took a lot of time but it was a very satisfying to see the results. It's not perfect. But it never was going to be once I'd tugged the seals off. It did leave me wondering though, how Citroen did it in the first place?

Cleaning The Carpets

 A long, hot spell was forecast, so I cleared the decks (quite literally) and cleaned my carpets.

Clean original carpet!

Like many old Ds, my carpets had years of ingrained dirt and grit. 'Clearing the decks' was necessary' as when the Pallas carpets are laid out flat, they take up a lot of room....

Look at the state of those!!!

Nearly all the carpets in my car are gold in colour. That was the colour used with 'veil or' coloured 'jersey rhovyline' seats/ interiors. I suspect the carpets were replacements fitted at some point down the line. Though the are right for the age of my car as the rear footwell carpet has two metal-rimmed slots in it for the seatbelt eyelets. 

I think this carpet isn't original to the car because the colour  differs from this piece. I think this may be the only original bit of carpet left on my car.

Caramel carpet piece from drivers footwell

It's caramel colour - which was the carpet colour fitted with 'naturel' leather colour seats. You can just about see how gold and caramel differ in this photo.

Both cleaned - and a noticeable difference in colour

This part gets trapped under the brake mushroom box and the parking brake pedal and is also screwed to the bulkhead(!)

'Caramel' carpet in the drivers footwell

So, if the rest of the carpet was changed in the past, I think this part was deemed too hard to remove and so it was left alone. If the rest of the carpet was as threadbare as this, I'm not surprised it was swapped for something better.

I also noticed that a lot of the gold carpet panels were loose - not glued down. Another sign that they'd been retro-fitted?

Loose panels in the passenger footwell

I'd carefully separated the thick foam from the floor carpets  - it was hanging off any way - and started by beating the carpets to get any loose dirt out. I did this by laying them face down on our trampoline in the garden and then beating their backs with a sturdy piece of wood.....I then placed them on the patio and vacuumed them to suck up anything that I could.

I did that a couple of times and got the carpets to a point where I felt they were about as clean as a 'beat and sweep' could make them.

I bought a couple of small stubby kitchen scrubbing brushes from B&M.

Carpet cleaning weapons

For the vinyl section on the carpeting fixed under the seat rail, I mixed some vinyl cleaner solution....

.....and used a stubby brush in a circular motion to raise a foam on the vinyl - which I then wiped away. I did this a couple of times and the vinyl came up really well.

For the carpets themselves I used our Vax upright carpet cleaner. It wasn't possible to use it in upright mode because of the bound edges of the carpets. Instead I used the extension nozzle. Initially I tried just using the spray function on the extension nozzle to apply cleaner, but the cleaner was sucked up before the cleaning brush was able to scrub the carpet.

I soon swapped tactics to liberally soaking the carpet with a pump-action spray gun filled with diluted carpet cleaner - and then using my stubby brush to get into the fibres and raise a foam. I then used the Vax cleaner extension to apply a bit more cleaner, scrub a little more and at the same time remove the dirt and water. I rinsed things with a hose pipe set to it's 'fine mist' setting and again used the Vax to remove the excess water

On a couple of occasions I even resorted to pre-soaking some pieces with a hose, before I applied any carpet shampoo. The process was longwinded and hard work - especially over two REALLY hot days, but the improvements were massive.

Rear carpet - partly cleaned

Front carpet partly cleaned

After cleaning, I didn't want to put the parts out in the direct sun for fear of fading, so squirrelled them away around the garden on chairs, benches and tables - where they could benefit from the very warm dry air, but not the sunlight.

Now that it's all dry, I've popped it into the car - just for storage at this point. There are a few Gauloise burns here and there but I really don't mind those at all. in fact I kind of like them.

I have a some spare carpet given to me by George Antoniou. 

They are very sun-faded  and from a right hand drive car, but I think I can use the passenger footwell piece to make a replacement for my caramel drivers side piece.