A Quick Word About.......Oil Filter Replacement

Before I try to fill the engine up with oil, I thought I'd better put the oil filter in. While I remembered......

I'm not going to go over the procedure for changing the filter as that's a routine maintenance thing. However if it's a job you've not tackled yourself (or you've never changed your oil!) then the  'DS Technical Team' people have produced a very handy video showing you how to go about it. You don't need a car hoist but if you plan to crawl under your car remember to support it properly on axle stands  - not the car jack:

DS Technical Team - Oil Filter Change

Well I don't know about you, but whenever I've changed my oil I've simply wiped the oil filler assembly down with a rag, popped a new cartridge on, then bolted the assembly back in. My focus has always been on three things: the new filter, the new gasket on the closing plate and the new washer on the sump plug.

It wasn't until I began the engine rebuild that I had cause to actually stop and consider (by which I mean 'clean') just how many pieces there are in that oil assembly. Lots! Here they all are:

Oil Filter Components......

In the picture:

Top row:

• Bolt
• New flat copper washer
• Pre-filter Plate
• Pre-filter
• Pre-filter 'O' ring
• Large Cup
• Spring
• Flat washer
• Ring Seal (small 'O' ring)
• Small Cup

Bottom Row:

• Sump Plug (with new copper washer)
• Cover plate
• Fixing Bolts and washers
• New 'Purflux' Filter
• New Filter Gasket

Phew!

You should really replace the copper washer on the bolt each time - which means pulling the assembly apart. And it wouldn't hurt to check the large and small rubber 'O' rings on the pre-filter and by the small cup. These go very hard and brittle over time so, before you go snapping them out in pieces (yes - that brittle), make sure you buy your replacements first! The other thing that goes missing is the small cup right on the end of the assembly.

All those parts can be bought from the usual suppliers and Citroen Classics have produced a video showing you how it all fits back together:

Citroen Classics - Oil Filter assembly

Anyway, having got the sump back on my car, I was finally able to fit the oil filter and it's cover - and that all important sump plug. Mustn't forget that.

Engine Rebuild (Part 7) - Studs and Inlet Manifold

With the head in place I went round and put in new studs for the inlet and exhaust manifolds, plus two replacements for the water pump housing. When the time comes, I've got new copper nuts for the exhaust manifold and locking nuts for the water heater pipe.

The cylinder head is odd in that some stud holes are 'blind' i.e have an end to them, whereas others are drilled right through into the water way. Ideally I would have used some kind of thread lock to prevent the studs from working loose, but with some stud holes open to the water way, it was more important that they were sealed again leaks. In the end I used Hylomar Blue on all the studs. 

Exhaust Manifold Studs Fitted.....

My thoughts turned to the inlet manifold.The inlet manifold had looked a mess.....

Mount Point for Clutch Re-engagenment Control 

When I'd first got the car going back in November 2014, I'd found a water leak under the manifold. It was impossible to get down there and find out why and where - especially in the gloom of the barn. I assumed it was a burst hose - maybe frost damaged. When the cylinder head was pulled in October 2015 I was able to look more closely and found the problem was actually a rusted-out core plug.

Silted Up Coolant Nozzle and Rusted Core Plug - 27 October 2015

I initially tinkered with the manifold earlier in 2017 and found that the little metal breather inlet (that takes a pipe off the sump breather tube) was completely blocked. I took advice and was assured that it was meant to be hollow. I eventually cleared out all the impacted silt with a small twist drill.Whatever it was meant to do - it hadn't been doing it for some time.

Cleaning the Breather Tube - 15 July 2017

I turned my attention to the core plug. Using a socket that fitted neatly within it, I tapped the rusted core plug into the manifold. I couldn't find a reference for it in the parts books, but It seemed to be coming up as 30mm diameter. I ordered a replacement from Ebay - for just a few pence. It wasn't quite as heavy duty as the original, but it was the best I could find.

Dead Core Plug

Having discovered the joys of vapour blasting in summer 2017, I put the inlet manifold through the process. It came out looking fantastic. 

Nice and Clean Inside - Excess Petrol Drain Hole

I fitted the new core plug. I smeared a little Hylomar Blue around the circumference and gently tapped it into place using a socket inside the cup of the plug. It seemed to fit quite nicely so I was happy with my choice of 30mm. Just to be sure, and using a screwdriver as a chisel, I bent over the three tangs that stop the plug popping out too readily.

The three gaskets for the inlet manifold are part of the engine gasket set and I soon had the manifold fitted and torqued-up. I'd ordered a new hose that runs between the water pump housing and the manifold and did a test fit.

Inlet Manifold Fitted

New Core Plug Fitted

Core Plug, Water Hose and Petrol Drain Nozzle

Engine Rebuild (Part 6) - Cylinder Head and Rockers

Putting the cylinder head on also means refitting the inlet valve rocker assembly as this is held in place by some of the cylinder head bolts.

Succinct assembly and fitting instructions for the rockers can be found at step 33 in Operation D.100-3 of Section 2 of Volume 2 of workshop manual 814.

When a cylinder head is removed, the inlet valve rocker assembly comes off in one long tangled, oily lump. 

DX2 Rockers on the DS - 27 October 2015 

The DX rockers had stayed that way since Adie first removed the head the day Richard and I went to pick the engine up back in November 2015.

Inlet Rocker Assembly

Now preparing for reassembly, and with frequent references to the workshop manual diagrams and part listings, all the parts were dismantled and accounted-for. The cylinder head bolts were difficult to with draw from the rocker mounts as the rubber oil seals on the base of the mounts had hardened. I ended up hacking the seals off with a Stanley knife.

Exhaust Rockers

Everything was present and correct and so was washed in Jizer. The long rocker shaft is hollow so that it can carry and distribute oil. I made sure the oilways were clear. Similarly, I made sure that the oil distribution hole on each rocker was unobstructed.

Inlet Rocker Shaft

After rinsing and drying with compressed air, I then subjected everything to a clean in the ultrasonic cleaner. This removed the last stubborn remnants of oil and dirt. As they were now thoroughly de-greased, parts were given a spray with WD40 to prevent flash-rusting.

I similarly took apart the rocker assembly from the DX2 engine – partly out of curiosity as it had looked so tired and worn, but also in case I needed donor parts.

Removing the DX2 Rockers - 10 September 2017

The exhaust rockers are lined with a (bronze?) bush with a lubricating hole. One difference I did notice between the two assemblies was that the exhaust rockers from the DX2 had an extra ‘tick’ shaped groove etched into the surface of the bush – presumably to aid oil distribution. The DX exhaust rockers didn’t have this.

DX2 Exhaust Rocker: Groovy

As I had expected, the parts from the DX assembly were in a better condition than those from the DX2 engine. Both long rocker shafts showed noticeable signs of wear, and this might also mean that the rockers were also worn. To replace the rocker shaft and four inlet rockers would have cost something in the region of £250 - and it was money I simply didn’t have. So the DX shaft (that was in better condition anyway) got re-used.

I reassembled the parts on the shaft checking the diagram in the repair manual and accounting for all the parts. 

Inlet Rocker Shaft: Ready For The Refit - 14 November 2017

Two important considerations: firstly, the rocker shaft has to be orientated so that the lubrication holes along it’s length are facing down and towards the valves. The shaft is also ended. Details of this are in Operation D.100-3 in the manuals. Secondly, the small support at the end of the shaft has to be fitted so that it’s bevelled edge faces ‘inward’ towards the rockers: this is to make room for the push rod to move past it. New oil seals for the base of the rocker mount towers were included in the engine gasket set I’d bought (I’d wondered what they were for!) and were subsequently fitted. The relevant cylinder head bolts were slipped into place…..

The cylinder bolt holes were blown out with compressed air and the engine block deck was checked for any lumps or grit that would prevent the head gasket sealing properly. The surface was a little pitted, and I had, several days before, dressed these imperfections with a little Hylotite Red. After it had cured a little, I used a Stanley knife blade to remove any excess.

With the tappets already in the block (don’t forget those!) the head gasket was put in position and the head ceremonially lowered. I was careful to make sure it sat correctly on it’s locating pins.

The cylinder head bolt threads were lightly lubricated. The push rods were put in their respective locations before the rocker/ cylinder head bolt assembly was lowered in place. The washers and springs were carefully jiggled into place to make sure that they sat either side of each bar cradle. The cups on the ends of the pushrods were aligned to the rockers, and the rocker ‘fingers’ aligned to the valve stems. Working my way up and down the row of cylinder head bolts, I gradually took up any slack on the bolts (without actually tightening them) to bring the shaft down into position on the many cradles. As I did this, I turned the engine - trying to seek the optimum position that meant that no single push rod was being put under undue pressure. I didn’t want to risk one bending.

Fitting the Inlet Rockers - 14 November 2017

I lubricated and fitted the remaining cylinder head bolts on the exhaust vale side. Studying the re-tightening order in the workshop manual, all bolt tops were numbered-up with a Sharpie – just to avoid confusion. As per the manual, I did a cycle of an initial tightening, followed by a final tightening. In fact I think I did it over four cycles – gradually increasing the torque each time. As I reached the higher/ final torque levels I held my breath – dreading a ‘ping’ as the block cracked or a bolt sheared. There were no problems and I could breath again. The rocker shaft lubrication pipe oil between the head and block was fitted with the new copper banjo washers that came in the engine gasket set.

With the cylinder head and inlet rockers fitted, the DX was starting to look like a working engine.

Getting There: 14 November 2017

Pleased with progress I put a message and photo up to the D Section Group on Facebook.

Then I suffered a setback…. I had refitted the exhaust rockers on their cradles and was torquing them up. The last nut wouldn’t reach the correct torque and I suspected the stud was turning in the head. I didn’t want it working loose when everything was assembled, so I removed it and added a little chemical metal. When I went back to finish the torquing the stud snapped! It must have been going ‘elastic’ – not turning?

Anyway, the only way I could get any mole grips on the broken end of the stud was to remove the whole of the inlet rocker assembly I’d previously fitted – that meant undoing half the cylinder head bolts….with the associated risk of one of those snapping too…..

I managed to get the stud out and replace it. As the threads in the hole were not at fault, the majority of the chemical metal I had added had been squeezed out when I put the stud back in  – so it wasn’t bound too tightly.

As I had to remove the head bolts on the inlet side, and on taking advice, I went the whole hog and removed them all – for fear of warping the head otherwise. Similarly, I decided I didn’t want to risk re-using the head gasket again, so sourced another from Citroen Classics – together with a couple of replacement banjo washers for the rocker oil feed pipe.

The gasket cheered me up as it was a NOS Citroen head gasket – rather than a Glaser brand one. Psychologically, and even though it wasn't that old, I just liked the idea of the connection that it represented to the past. So much so that I took a photo:

In short, I had to go back and refit the head and rockers from scratch! Having started fitting the rocker assembly in mid November, it wasn’t until the end of December that I finally had all the rockers back on. Not a bad way to end the year though.

Exhaust Rockers - Finally Fitted.....

Fuel Pump Strip Down and Rebuild

My fuel pump looked a mess......

Fuel Pump - 7 June 2015

Even though modern, reproduction fuel pumps are readily available, I was keen to try to retain my original and distinctive 'SEV-Marchal' pump. I had re-plated the top cover back in 2015, but have only just got to the point where I need to be refurbishing and refitting the fuel pump. Instructions for rebuilding can be found at Operation DX. 173-3, which can be found in section 2 of volume 2 of Citroen workshop manual 814.

Orientation of the Two Pump Valves

The upper and lower body were unscrewed. The seal under the domed top cover was very, very carefully prized off the pump body and feed tube using the edge of a stanley knife blade, allowing access to the two valves within the chambers. These are orientated in opposite directions and I took a reference photo. Despite what step five in the Workshop manual suggests, I was able to remove the valves. I planned to use a socket to drift the valves out, but found a socket too chunky for what looked to be quite delicate valves. Searching around I found that the 22mm end of a copper plumbing pipe reducer was a good fit for the diameter of the chambers. The valves were then easily removed. The key is to put your chosen tool in the dished side of the valve, so that the sharp edges of the valves are pulled - rather than pushed - through.

Moving on to the bottom half of the body, the cam that operates the pump was released by carefully removing one of the tiny locking circlips from it's groove in the cams spindle. The cam was then unhooked from the base of the operating rod inside the lower body, allowing it to be pulled out -  freeing the spring within. There were also two spacer washers that fit inside the body on the spindle.

Soldered Bolt on Diaphragm

The bolt holding the diaphragm assembly together is locked with solder. I suspect that this is to set and maintain the correct operating force (pumping force) on the diaphragm spring. With this in mind, I marked the orientation of the bolt to the diaphragm before unsoldering it, and made a note of how many turns it took to separate the bolt from the operating rod.  (Note: In Step 3 of Operation 173-3, the diaphragm and attached rod are removed as one - without removing the soldered bolt).

The small black rubber cup at the cam end of the operating rod was as hard as rock. In fact at first I wasn't even sure it was rubber. It was the workshop manual that confirmed it was. These parts aren't obtainable as spares and so it was make or break. I left the rod and cup soaking in a mixture of wintergreen oil and isopropanol alcohol for a couple of days*.

Wintergreen oil is the smell you get in Deep Heat. It is a very strong smell. People tend to either love it, or loath it. I left my parts soaking in the green house so that I didn't stink up the workshop! Personally I like it - but not in these quantities and strengths. I accidentally getting some of my mixture on my hands: the smell travelled everywhere with me. I poured some in a saucer. Despite washing it thoroughly first, dishwashing the saucer caused the whole dishwasher load to stink!

Miracle of miracles, after a couple of days the rubber cup began to soften with no signs of swelling. I left it a few more days but didn't want to push my luck. The pump diaphragm was showing signs of fatigue. Removing the metal plates that sandwich it, I gave it a bath in my wintergreen mix. Again, this had the effect of softening it.

Components of My SEV-Marchal Fuel Pump - 16 December 2017

With the valves removed and the rubber parts salvaged, the two halves of the body were taken away for vapour blasting - as was the metal spacer plate that fits between pump and engine. All the parts were then carefully cleaned before re-assembly.

The diaphragm sandwich was reassembled and the bolt tightened as per the note made during removal and then re-soldered. Reassembling the cam on the operating lever was fiddly because of the need to also align the spindle spacers in the body. I VERY carefully teased the circlip back on the end of the spindle and, after cleaning the end with alcohol, sealed it on with a small blob of Araldite.  The valves were refitted - again using the copper water pipe reducer - and the body re-assembled. 

Rather nervously I followed the instructions in step 12 of Operation DX.173-3 and tested the pump by emerging it in petrol and putting it under a little pressure to check for leaks. It passed muster. After draining, the spindle and cam were lightly lubricated with clean engine oil and I fitted the pump to the car. The smell of wintergreen oil dissipated (after about a week!).

Fuel Pump Fitted

* CAUTION: there are different compounds of rubber and there is a danger that some may react badly to soaking in wintergreen oil and/ or alcohol. This may take the form of swelling (growing alarmingly in size) or the surface dissolving (black sludge rubbing off on your fingers). If you are tempted to try this but cannot afford to risk ruining a piece, then you would be better off finding another way.

Engine Rebuild (Part 5) - Exhaust Manifold Prep

The exhaust manifold has studs for a protective heat shield and also studs to hold the air cleaner on top. All these studs were quite badly pitted and rusted and the manifold itself looked very rusty. I decided to replace the studs and repaint the manifold.

Stud for Mounting Air Cleaner - 19 November 2017

I'm planning to use a high temperature manifold paint. It should really be cured at a high temperature - higher than the oven in the kitchen can produce. Alternatively you can cure the paint by running the engine. I think that's the way I'll have to go.

Where I'd expected to find studs between the manifold and downpipes, I found a couple of bolts.

Bolts Instead of Studs?

I'd already bought and fitted new studs to bolt the manifold to the cylinder head. In addition  I'd gone ahead and bought replacement manifold to down pipes studs, and studs for fixing the heat shields to the manifold.

New Studs and Nuts for the Refit

One Sunday afternoon in November 2017 I set to work trying to remove from the manifold, the rusty stumps they were going to replace.

Double-nutting did nothing. I just stripped the threads on four nuts. Tackling each stud, I had to use my biggest mole grips set as tight as possible to get any purchase on the studs.  They had to be repositioned copious times to maintain any grip and the threaded studs were  starting to shred.

With an insistent wiggling action I began to sense microscopic movement in a stud and blasted it with some Plus Gas. A little more wiggling, a little more Plus Gas and I could feel definite movement. Persevering in this way - lots of wiggling and Plus Gas - I was gradually able to great greater rotation on each stud and teased them all out this way. Well, most of them. One snapped and had to be drilled out.

Out With The Old, In With The New....

With all the studs removed, I put them back in again! Just loosely. I was sending the manifold off to be blasted and didn't want all the stud holes blocked up or the threads damaged. My workshop guy blasted the manifold and downpipes, then he gave them a squirt of WD40 to stop them rusting. 

I actually wanted them as grease-free as possible to give the high temperature paint I planned to use the best chance of adhering. Never mind. I think I will probably have him blast them again but leave them dry next time.

A Quick Word About..........Cylinder Head Bolts

I knew that the cylinder bolts on the inlet and exhaust sides were different lengths, but I hadn’t appreciated that the lengths of the exhaust side bolts on early DX engines are shorter than those on later DX and subsequent DX2 engines. It’s all about washers.

The cylinder head bolts on early DX engines were fitted without washers and so pressed directly against the cylinder head surface. The exhaust side cylinder head bolts on later DX engines and thereafter were used with a thick washer – presumably to minimise compression damage to the alloy head. The upshot is that the bolt is correspondingly a little longer to compensate for the length taken up by the washer. The parts books give the two lengths as 111.5mm up to July 1967 and 114.5mm thereafter, when a 3mm washer was also used.

Early (top) and Later (bottom) Exhaust side Cylinder Head Bolts

Fitting the 3mm Washer Brings the 'Working' Length Back to 111.5mm

Bolts on the inlet manifold side stayed at 160mm throughout and weren't used with washers. There was no need: they bolt to the head through the inlet rocker rail so the head already had something of a 'cushion' between them and the head.

Anyway, when my engines were stripped, several bolts on the exhaust side snapped on removal – and some of the rest were rusted and pitted. These exhaust side bolts are the ones most likely to fail (not only on removal but also on reassembly) and so are the ones most likely to be replaced.

Failed Exhaust Side Cylinder Head Bolt

For this reason I bought lovely new replacement exhaust side cylinder head bolts. As I have written elsewhere – many of the reproduction parts are geared to DX2 engines – not DX. The replacement bolts I bought are 114.5mm long and so are a little longer than the ones originally fitted to the early DX engines. There is a risk that if I had gone ahead and used  new, 114.5mm bolts on my DX  engine without  washers, the bolts could have ‘bottomed-out’ in the tapped holes of the block before they were sufficiently torqued:

• Leaving them at that point might have meant that the head gasket was not properly sealed - and failed down the line
• Continuing to try to torque the bolts when they had bottomed-out possibly risked the bolts snapping – causing quite a headache or:
• Continuing to try to torque the bolts when they had bottomed-out risked cracking the block – which would be even worse.

This may sound alarmist, but I found something that suggested i might not be crazy after all....

Thread from the "DS Club Deutschland" Forum

'Pit' had leaks on his DX engine and attributed the problem to head skimming. He was trying to solve the problem with a marginally thicker, hand-made head gasket. As 'HGK' was suggesting, perhaps his bolts were bottoming-out.

It just goes to show what a little bit of research can unearth. In my case, and as I had a DX2 engine in bits as well, I was able to use the 3mm washers from that engine.

114.5mm head bolt........with 3mm washer

Engine Rebuild (Part 4) - Fitting The Valves

By mid September 2017, and after an initial clean up, I had been soaking my DX exhaust valves in Mek pretty much since mid August. This loosened some of the burnt on muck - but not nearly enough. In the end I had to resort to using my wire wheel to clean them up. I was very glad I did as it did a great job. I was very careful to avoid going too far up the shaft of each valve with the wheel as I did not want to introduce scratches.

At the end of September 2017 - while researching cylinder heads and valves -  I was lucky enough to find a set of NOS DX inlet valves for my 1968 car.

New Old Stock Inlet Valves - October 2017

These were the earlier 47mm diameter valves, BUT with the three groove cap and collar. They were only fitted for about 15 months between May 1967 and July 1968. Result! (See my other post on DX valves for more on this).

September and October were spent getting the cylinder head ready - including vapour blasting, skimming, fitting new valve guides and having the valve seats re-cut.

By mid November it was starting to come together: I  had my cylinder head, my valves ready and all other associated parts had been thoroughly cleaned and oiled. I was ready to go.

Underway - 12 November 2017

I spent an afternoon lapping the valves. This process was not nearly as long-winded as I thought it was going to be - possibly because half my valves were new and - more likely - because the all valve seats had been re-cut. The objective is to keep lapping until you have a solid, clean ring showing on valve and seat - meaning the surfaces are flush and a good gas seal. The tone of the grinding note changes as you reach that point. It was really quite satisfying. After lapping I carefully wiped up all traces of grinding paste.

With my new valve spring compressor, I was able to make quick work of re-fitting the valves.

Fitting The Valves - 12 November 2017

Compressing the Springs to Slip the Collars Around the Stem

Working methodically, I was soon done. I was very pleased with the results and finished the day by re-fitting the tappets. I couldn't resist sitting the head on the block and adding the push rods.

Valves and Pushrods - 14 November 2017