There are a few ways the engine can be offered into the engine bay on a Citroen BX, and I’ve tried a few over many years of BX ownership. Where little lifting kit is available, the engine can be slid under the car, lifted up, and the gearbox added later. It is possible to lift the complete engine can gearbox in from underneath. But I prefer to lower the engine and gearbox into the engine bay as one. This is the method used in the workshop manual. That means I need to do some work on the 16v gearbox, flywheel and clutch to get it all bolted to the engine.
Flywheel
When I first took apart the gearbox and engine that used to reside in G-SEG, I panicked a little. Alongside the many horrors found when taking the engine apart, the gearbox wasn’t much better!
The image above is how the flywheel looked even after a good scrub in the degreaser. There were many scorch marks on the flywheel, which made me a little concerned that it might be warmed. I lost my spare flywheel when it went off to be lightened and never returned.
However, my concerns lessened once I applied an engineering straight edge to the clutch face. It was, in fact, lovely and level. A quick surface dressing removed the worst of the scorching.
On the ring gear side of the flywheel, the starter seems to have had some issues in the past. The damage looks a little like someone tried to start the engine when it was already spinning. The worst of the teeth were dressed, hoping to reduce further starter motor damage.
Clutch pack
After seeing the burn marks on the flywheel face, I went to the XPO scrap pile to find the original G_SEG clutch plate. I might know what the issue was by looking at the part numbers and appearance.
The correct 215mm clutch plate for a Citroen BX 16v is 2055.F3, which equates to 96 173 738. What was fitted is 96 300 258, and I have to say I’ve never found what this clutch plate is actually for. However, the springs make it clear that there will be too much clamping force for the 16v. This is likely the reason for the scorching on the flywheel.
Unfortunately, this is the last 2055.F3 clutch plate that I have for my BX 16Valve, but it needs to be replaced. The clutch plate is assembled to the installed flywheel under a new Valeo clutch mechanism. My dad turned the precision alignment tool for me in about July 1999. Despite its appearance and the many clutch changes it has helped with, the alignment is always perfect!
Clutch Release
I’m turning my attention to the gearbox, and both the upper and lower clutch fork bearings look unhealthy. The plastic bearings are easy to change once the clutch fork is out.
However, getting the clutch out proved to be a bit of a nightmare. The securing pin should ‘knock out’, but it absolutely won’t. The M7 thread should allow the pin to be drifted out. Unfortunately, the thread is damaged, and the pin is bent.
Trying to remove the securing pin quickly turns into a battle of wits. Despite plenty of heat, the pin simply will not move.
Ultimately, I managed to get the pin moving, but in the wrong direction. There isn’t enough clearance for the pin to come out backwards in one piece. Instead, the pin is slowly cut down as it slides out.
And if that wasn’t enough, the lever arm still won’t come off the shaft. No amount of heat or BDX will free it off. Instead, a few pieces of Citroen tooling are modified to become a shaft puller. Fortunately, a rattle gun does most of the work, and the lever arm comes off with a bang.
Reverse Switch
In the process of releasing the stuck fork lever and replacing the clutch fork bearings, ever-bigger hammers were employed, along with copious amounts of BDX, fire, and, ultimately, a fair bit of force.
As any experienced mechanic will tell you, big hammers are a form of divining rod. Rather than finding water, hammers tend to divine delicate, usually expensive, electronic components. This day was no different, with the reverse gear switch being knocked clean off the top of the gearbox. The destroyed switch was quickly replaced with a new old stock part.
Gearbox Rebuild
Once the key parts of the BX 16v gearbox were disassembled, the gearbox rebuild could begin.
First up, the clutch control arm bushes are changed and the lever reinstalled. I contemplated ordering a replacement M7 pin, but I have a lathe and plenty of M8 bolts. Hopefully the next guy should have a better time of getting this pin out with the bigger M8 thread.
The gearbox also gets a new guide bush and release bearing. Along with the new clutch pack and some new oil, this should ensure perfect gearbox operation once the engine is back in.
Part Numbers
I have always been amused by the number of markings in the various sections of the BE1 and BE3 gearbox castings.
The main assembly part number is on the top of the gearbox. I guess this technically sits on the bell housing. The BE3 is easy enough to decipher, and the 94312020.21 is the Citroen part number. The 3.2846.03.31 is likely the manufacturer’s part number.
Moving back along the top of the gearbox there is a ‘BE3 TT’ marking. Again, the BE3 is simple enough, but I’ve no idea what the ‘TT’ represents.
Finally, on the front of the 16v gearbox, and upside down, are the identifiers ‘CJ44 A’ and 678632. I believe the CJ44 relates to the gearbox type and the gearing. Unfortunately, I’ve not been able to link the numbers to anything meaningful.
Gearbox Rebuilt and Engine Assembled
Despite it being more than six months since I first looked at the flywheel, progress has been made. The main serviceable parts of the 16v gearbox have all been replaced, hopefully in the correct order. There is only one thing left to do.
Despite being separated for nearly three years, the engine and gearbox slip straight together. That 25-year-old clutch alignment tool struggles to be beaten. I do have the genuine Citroen/Fenwick tool, but why change it? Either way, we’re getting close to the engine returning to XPO. While this should be a cause for celebration, it does raise some key questions.
Have I put it together properly?
Will it start?
How many leaks does it have?
I guess only time will tell!
M
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