Citroen 2cv special tools | home
push rod tube extraction and insertion tools
the push rod tubes are sealed, to prevent any oil leaks, with a special Citroen tool, that roles the inside of the tube that creates a tight fit into the head bores. They are rolled and sealed in 2 positions each, at the top of the tube and where it exits the head area. These tools are unavailable anymore, so I have created an alternative. It is a bit slower to achieve the desired results but with a bit of patience, non the less, it does it correctly.
One tool knocks the tube out of the bore. Where the tool fits into the tube, you will see that the tube penetrates into the head space by about 2mm. This is the point where the tool will start to knock the tube out, so care must be taken, to not damage the tube or flare it over, as it could scratch the bore.Gently knock the tool down and the tube will move. Citroen said that you must hacksaw the tube length off and then hacksaw the tube inside to split it and then knock it out. This is unnecessary and could, if not done really correctly, totally render the head useless. You do not need to saw the tube in half either as all you are going to do is to knock it out, carefully.
Clean and inspect the 2 bores. They must be spotless. Look inside the bores and you will see that the aluminium is separated by the fins into 5mm wide sections. Only at the top and bottom of the head are solid parts and this is where the tube seals, not on the entire length of the bore. Insert a new tube, carefully, and position it correctly to its correct protrusion out of the head bottom until it is about 2mm proud of the head at the top. The tool used to crimp the tubes is called a tap and turn tool. It has some ring marks on it to show you the depth it has reached and it also has a 1 degree taper, on a part of its length, which will spread the tubing and create a seal. You must oil the tool frequently and also keep withdrawing it. Gently enter the tool into the new tube and very gently turn it. You will feel it grip, thats the taper doing its job. Constantly watch the 2mm bit at the top and make sure that it always stays at 2mm. Pushing too hard on the tool can push the tube down too far and then you have a problem. Keep tapping the tool in and keep turning it, half a turn at a time and withdraw it and re-oil it. Go slowly, only gently tap it. When the tool reaches the ring mark, that part is finally crimped. Now, you have to knock the tool down to another mark by going past all the fin separations and start all over again tapping and turning and withdrawing and oiling. Take the tool down to the final ring mark and all you have to do is to withdraw the tool. Knock the tool up and out with the aid of the supplied drift Job done, success.
top-------tap and turn tool that creates the sealing crimps
bottom--------drift to extract the tube
not shown----------additional drift to dismount the tool