:: Fitting a 156 rocker cover to a 16V TS ::

There are a few benefits from fitting a 156 rocker cover to a 155. The first one is that it is visually bigger and better than the standard alloy cover of the 16v cars. Secondly it is made of plastic, so does not corrode and wipes clean. Thirdly it has a better oil seal round the sparkplugs than the original.

So what do you need for this conversion? Well you need both pieces of the cover; the silver top and the black underside, the appropriate rubber gaskets round the edge, a length of pipe the same diameter as the breather pipes (I've forgotton the spec for this now), a couple of jubilee clips and a piece of earthing wire with crimped eyelets on either end.

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Start by removing the spark plug cover as in the above picture.
Remove the coil packs on their bar and then the alloy rocker cover. Also remove the breather pipes on the Y-piece to the right of the cover.
At this point it is wise to get some tissue down the plug holes and soak up the oil that has run down there. The plugs on the right hand side seem to get it the worst.
Also clean up the contacts on the plug to coil packs too.
This gives you another view of the bare head. Clean up the areas where the seals will sit and make sure they are smooth. Take note of the way the inector leads are spaced out. You will have to remove the brittle plastic rail (always snaps!) that contains these leads. These will tuck neatly under the new cover.
At this point put the new black cover on with all the seals. The Y piece crank case breather has changed on the 156 to more of a T piece. This means the existing pipes will not fit as before. However you can reuse the top pipe in the bottom position. The new pipe has has to be looped round the long way if a piece of pipe with no elbow is to be used. The length of this pipe is not really important as it is only a recirculation breather for the crank case.
As the new cover is plastic, it will not conduct electricity, so the coil packs lose their earth to the rest of the block. This has to be compensated for by creating another earth. Attache a thickish wire from the right of the coil pack rail and run it to a suitable earth on the rest of the engine. There is such a place on the block just under the breather T piece.
Reattach the new silver cover and line up the injector wires nicely with their little white tags showing through evenly (it can be done!).
On this picture you can just see the breather pipe looping round at the top right.
The standard filler cap from the 155 fits the new cover.


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