Fettling The Replacement Outer Sill Panels

When you use replacement parts, It's probably wise to assume that some fettling will be needed to make them fit and function as intended. On a whim, I decided to do a test fit of the pins that hold the door springs and spring mechanism in the new sills.

Old and new compared. Spot the difference?

I'm so glad I did because..... the pins didn't fit. They were too tight. I'm glad I didn't find that out after I'd welded the sills in place, as it would have been awkward to access that area.

A cradle and pin in situ under the sill

In fact it wasn't even easy to rectify with the panels still off the car. The shaped edge of the sill panel also meant that I couldn't easily get a file in the holes to make them a little bigger. In the end, I put a pin on my tower drill, spun it and used emery cloth to very slightly reduce it's diameter so that it fitted. 

But it got worse. Fitting the pin showed that the cradles that the pins sit in were too wide. This is quite significant as the cradle has grooves for the springs and for retaining circles, and shoulders the rest in the cradle.

Citroen sill and cradle: aligned to the pin shoulders

On the new parts, the cradle arms aligned to the grooves  - rather than the shoulders - and so might dislodge a circle-or door spring when in use.

The cradle is wrongly aligned to the grooves

I tried bending the two sides of the cradle together, but with the sides no longer parallel, the pin wouldn't fit again! Luckily I hadn't thrown away the old sill panels I had removed and, given these two problems, decided to salvage the original cradles and re-use those. On the old Citroen parts, I carefully drilled the spot welds out from the panel side, making sure I did not cut the cradles. And I carefully drilled out the spot welds from the cradles of the new panels - making sure i did not cut the panel beneath.

Removing the cradles

I compared cradles. The ones from the reproduction panel were so over-sized (wide) that the Citroen cradles could nestle within them! They would have taken some significant re-shaping to reduce the gap and still have the two sides parallel.

The reproduction cradles were over-sized

The spot and drill marks of old and new panels showed me where the donor cradles needed to go and they were soon welded back on to the new panels. 

Telltale marks aided the re-fitting

A test fit of the pins showed every thing was as it should be....I gave the repair areas a basic wash in thinned zinc oxide primer just to prevent fish-rusting and in the expectation that it would wick between the cradle and the panel.

A Quick Word About..........The DS Fuel Tank Filter

When I removed the fuel tank from my car earlier this, I discovered that it didn't have it's proper in-tank fuel filter fitted to the drain plug. So I started to look into it.

Fuel tank filter and fuel tank drain plug

The in-tank filter consists of a column of thin serrated discs, stacked over a cage-like plastic frame.

The discs are stacked over a plastic frame

The serrations mean that there are very small gaps maintained between the discs. That's how and where the filtering takes place.

The filter unit presses into a recess in the end of the brass fuel tank drain plug.

The recess in the fuel tank drain plug

The other, top, end of the tower has a small hole to the space in the middle of the disc stack. The fuel tank has a curved metal guide tube that the nylon fuel pick up hose fits through. The guide tube ensures that the nylon pick up hose passes down into the middle of the fuel filter stack.

The guide tube 'A' steers the pick up hose into the filter 'F'.

The tank end of the fuel pick up pipe locates within the stack of filter washers via the hole in the tower.

The filter in the tank. Note the rust!

(photo credit: Carter Willey)

All too often, when the drain plug is removed, the stack of filter washers is found to be clogged and looks like this........ 

Clogged filter
(photo credit: Enzo Round)

It's hard to even recognise it as a stack of separate discs.

Faced with this, some people choose to leave the filter out of the tank and instead use disposable in line filters. The in-tank filters can, however, be dismantled and cleaned to restore their function.

The version of the filter you are most likely to come across consists of bronze discs. Removing the 'lozenge' from the end allows the clipping end of the tower to close up slightly and the washers can be removed more easily. First of all there should be a plastic washer on the end. Next is a rubber 'O' ring.  

Fuel filter
(photo credit unknown)

It's not uncommon for the 'O' ring to perish or be completely missing.......

Perished 'O' ring.......

Under the 'O' ring are approximately 60 thin bronze discs or washers.  

Filter dismantled.
(photo credit: Colin Smith)

I can only say 'approximately' as some folk find they have 60 or 61 washers, others find just less than 60.

59 bronze discs and a plastic washer. No 'O' ring.....

Whatever the number of discs, you don't want excessive gaps between them. That's why the rubber 'O' ring is important - to take up any slack in the stack. If it needs to be replaced, the 'O' ring needs to have an inner diameter of 21mm and have a cross section of about 3mm. Thats assuming you have about 60 bronze discs.

The individual discs can be carefully cleaned. An ultrasonic cleaner is handy for this kind of thing and hanging the washers from a threaded rod means the washers don't gather up. Elbow grease works too.

Cleaning the discs in an ultrasonic cleaner

If properly maintained, the in-tank filter does exactly what it's intended to do.

Cleaned filter. Can you see the gaps?

The filter assembly should clip into the end of the drain plug and stay there - not just sit loose. Though there isn’t really anywhere it can go.

Plug and filter assembly
(photo credit unknown)

When refitting the drain plug and washer, it's wise to make sure that the end of the nylon pick up hose extends fully to the bottom of the tank  - level with the base.

Fuel pick up pipe at tank drain hole
(photo credit unknown)

The drain plug and filter assembly can then be fitted over the fuel pick hose and screwed home. It's also wise to make sure that the end of the pick up hose is cut at an angle. If it's cut square, it may block itself at the bottom of the filter stack.

Pick up pipe inside the filter. Note the angled pipe end

As the filter was missing (or removed) from my car, I got a second hand one from one of the usual parts suppliers. I was surprised to find that, instead of about 60 thin bronze discs, it was made up of 39 slightly thicker serrated plastic discs. The 39 plastic discs equated to the same length/ height as 60 bronze discs.

Serrated plastic discs

Perhaps this version is from the end of DS production or maybe from a contemporary Citroen model? It still works in the same way though.

Sill Box Section Repairs

One job seems to lead to another......

Unfortunately the work to replace the non structural outer sills revealed more jacking damage!  This time to the box sections. The damage was just rear of the proper front jacking point of the car. And on both sides! At some points in the dim and distant past, someone had jacked up the car from under the edge of the main sill - on the fold.

Rust on the sill!

The fold is the join between the floor pan and the outer face of the main box section.

The damaged area is shown by the red circle

The edge had folded slightly - breaking through the underseal. I might otherwise have left this, but, over time, the creased edge had rusted through......

The underseal promotes AND hides the rust

I removed some of the underseal to assess the damage. It was just the folded seam that had rusted - a length of about 20 cms long and 2cm deep on both sides, however repair work meant cutting into good metal slightly higher up.

Cutting out the rot

And on the right side of the car, the folded vertical edge of the floor pan  - that I needed to weld against - was also badly corroded. Meaning that I would need to let a patch in there too.

The area behind the spot welds was also corroded

I cut very slightly into the floor pan, then formed a profile in a vice and cut a piece to suit. 

Forming a patch

The fold in the patch meant I could butt-weld a flat edge to the floor pan, rather than trying to weld a patch on at 90 degrees.

New 'lip' welded on

The new lip gave a good clean edge to weld-to and the patch was soon fitted.

One done, one to go....

The repair on the other side was similar, though no patch to the floor pan lip was needed.

Note the plumbers matting to protect the pipes from cutting and welding.

The rest of the sill looked to be in good shape - though the Waxoyl I had sprayed in , in about 1995, had dried out and curled up. It's Dinitrol for me next time!

The floor pan in the sill looked good

Another patch was cut and fitted. 

Sizing the patch for the left hand side

With both sides repaired, surely now I could press on with replacing the outer sills? Well - maybe  not quite yet......

Outer Sill Replacement - removal

I find myself carrying out a repair I hadn't expected to do - but I suspect that is naive of me as the outer sill as notorious rust traps - but most DS owners remain blissfuly unaware of the corrosion hidden away behind the sill trims until it is very advanced.

Replacing the outer sills

When I was starting work on the car, back at the farm in 2014, it became clear that at least one of the front jacking points was corroded and would need some kind of repair.

Rot in the right hand jacking point. 

You can read about that repair HERE. 

It was barely visible but under all the road dirt and grime, but at some point in the cars past, someone had tried to jack the front of the car up from the outer sill on the left hand side and had damaged the sill cover.

Hard to spot: telltale damage to the sill cover

I guess this was either before my ownership or when I owned it but it was sitting abandoned at the farm. The car had been moved around several times then by 'non-DS' people, finally ending up tucked away in a corner.

Fast forward to December 2019 and I was beginning the work to replace both jacking points. Over the Christmas break I removed the carpet and trim from the sills to give me better access to the base of the 'A' posts.

I started by removing the dented lower stainless cover from under the sills. This was dirty and the screw heads were rusted in. 

The screws holding the spring mechanism for the rear door had to be removed. The main bracket straddles the 'B' post and is held in place by two large dome-headed screws on either side, released from the outside of the sill. 

Retaining screws for rear door spring mechanism

On the top of the sills, pulling back the Pallas carpet revealed a row of screws holding the carpet finishing trim to the sill top surface. The sill trim was held down by this.

Screws are hidden under the carpet edge

In some places the edge strip was simply holding the main sill trim down, but there were a couple of screws. Again, the screws were rusted in and the heads corroded. particularly in the corners by the rear seat.

Rusted screw head

In most cases I needed to resort to an angle grinder to remove them. Access was limited and some collateral damage to the stainless trim was inevitable.

Angle grinder damage

The vertical edge of the top trim sits in a groove above the bottom white, rubber, door seal. Removing that strip......

Screws are hidden under the top trim piece

....gave me access the the stainless steel trim on the vertical face.

Removing the finishing strip helps to release the vertical face trim

Removal of the outer trim revealed the extent of the jacking damage. Luckily it was just a crumpled outer sill. 

Crumpled outer sill

Thankfully the outer sill is non-structural as there is an inner box section that gives the chassis it's main strength. The outer sections provide convenient 'ducts' for channeling pipes, cables and rods between the front and back of the car.

Construction of the sill. Left side from rear door forward

Removal of the trim also revealed the almost inevitable corrosion along the underside of the outer sills where the trim fixing screws had been. That rust undoubtedly weakened the outer sill too. This rust is pretty typical for a DS.

Typical rust areas in DS sills

The rust here probably weakened the sill and so further reduced the likelihood of it bearing the weight of the car when it was being jacked. 

In my case I judged that just about the whole bottom edge - most of the length of the car on both sides  - would need to be patched with long, thing strips wellded-in. 

Just about the whole bottom edge was rotten

That represented a lot of welding as far as I was concerned. And there was  also a high risk of warping and distortion. And I would need to do it lying on my back. I decided, like others before me, that it would be simpler  - and provide a longer term fix - to totally replace the outer sills. It's not a decision I made lightly as I want to keep as much of the original car as I can. However these pieces were on their way out, were tucked away out of sight and, as the outer sills are not structural, I decided to replace them. The replacement parts were ordered up.

A box of goodies: 31 March 2020

When the cars were first built the outer sill panels were one piece and ran from beneath the 'A' post to beneath the 'C' post with the 'B' post sitting on top, half way along.

The outer sill is the bottom horizontal edge of the top piece...

The original outer sill was a single piece per side
(Photo copyright Jint Nijman)

Most repairs/ replacements will only be to the  between the door posts. So the replacement panels are sold in two parts and need to be cut to length - depending on how much is being replaced.

Replacement outer sill panels: two per side

By mid May I had cut out the old sills - starting with the left side of the car. 

Working from under the car I completed removal of the rear for spring mechanism by removing various circlips and springs to release the rollers and arms.

Bracket for rear door spring mechanism

It was then a case of winkling out the bracket from the 'B' post.

Removing the spring mechanism

Removing the sill was then a case of drilling out the spot welds along the top surface and  cutting through the vertical faces of the rotten sills at the appropriate points.

Drilling out the spot welds

In both cases, and on both sides of the car I was very carefully to avoid cutting or damaging the various pipes and cables hidden within the outer sills. I was able to get a good cut line on the back end of the left sill, but still needed to cut out the remains of the channel for the door rubber as it had rotted away.

Removing the channel that holds the door rubber

I think capiliary action must draw water up inside the channel. Don't let anyone ever tell you they have a 100% 'rust-free car'......

Notice the pipes and cables within the sill - careful!

The front end of the back section was more difficult. In the photo below you can see that the large aperture in the sill piece is very close the base of the 'B' post - where the channel that holds the rubber door seal is located. 

The edge of the aperture is close to the vertical seam

That would be awkward to weld. As with the back end, the door rubber channel was already rusted, so I removed the bottom section to give me a better cut point on the sill further from the aperture. That was quite destructive......... 

Looks a mess but is easily repaired

.......but gave me a little more welding room to work with.

Sizing up the replacement panels

I applied the learning from tackling the back section to similarly removing the front section of outer sill.

Cut line on the front half of the sill

Remember this grainy photo of the door spring retaining screws? 

When replacing panels,  keep this distance between the screw holes the same!

One very important consideration when sizing and cutting the replacement panels to fit the gaps you have cut out, is to make sure the holes between the front and back patch pieces are the correct distance apart to enable you to refit the door spring bracket. Don't be tempted to move a panel slightly to make it easier to weld.

Make sure you keep this distance the same as on the original panel!

With the old outer sills removed, the extent of the rust was clear. I could see how it was centred around some of the holes where the trim fixing screws were secured.

Rust around the screw holes

I could also see the extent of the damage caused by the ill-advised jacking attempt.

That jacking damage......

I went on and repeated the same exercise on the right and side of the car - removing front and back sections of the outer sill.

With the outer sills out of the way, I got a better view of the actual box section sills behind them. And it turned out that meant more work! So my outer sill replacement journey ends here for the moment.