15.1. VALVE CLEARANCE

Every 15.000 km the valves need to be adjusted. For a good working engine it’s necessary that the valves work flawlessly. On both sides of the engine there is a cylinder head where there are a total of four valves; two inlet valves and two exhaust valves. The exhaust valves are particularly heavily strained thermally.
They are of course made for it, but because of the heating, and therefore the expansion of the valve, there must be a bit of space between the valve stem and the valve rocker. Not too much because then the valves do not open wide enough. But certainly not too little because then they cannot close.

The adjustment as described is valid for the engine 602cc, such as the ones delivered on the 2CV6 and the Dyane.

The valves must be adjusted on a cold engine. (Minimum for hours of not driving).

- First the valve covers are removed. Loosen the valve cap with a wrench 12. Sometimes it is necessary to use a plastic hammer and tap the cap before this one comes loose.
- Place a container under the valve caps when you are removing them to collect the running oil.
- Check the valve of one cylinder when the same valve of the other cylinder is completely open. So, when the left exhaust valve has to be adjusted / checked, the right one should be fully pressed.
- The valve margin can be measured by placing the feeler gauge of 0.20 mm between the valve and the valve rocker. If the feeler gauge can just fit between them, then the margin is in order.
- The valve margin for both inlet and exhaust valves is 0.22 mm.
- If the valve margin is different, the valves should be adjusted.
Adjusting the valves goes as follows:
- Loosen the lock nut of the adjusting screw with a key ring 10, and then the adjusting screw can be rotated until the feeler gauge of 0.20 mm can just fit between the valve and the tip of the valve rocker arm. (See figure 3C.1)
- With a screwdriver, hold the adjusting screw and set the lock nut back. Check the valve margin again.
- Clean the valve cap by the gasket good and always use a new gasket.
- Glue the valve cap gasket to the caps, do this with liquid gasket, (do not use silicon gasket).
- Tighten the cap nut of the valve cap with a wrench 12 until the cap cannot be moved by hand. Tighten the nut again. The caps are now very tight. (5.6 Nm).

RELATED PARTS

>>Rocker cover seal