Hi scavpan,
that “canal” goes directly to the exhaust port. You can see a hole close to the outlet valve.
Original idea is to get some fresh air via tubes, vacuum switch and controlled by a membrane into the exhaust when there is lower pressure than on the intake side to “reburn” the fume and minimise hazardous substances in the exhaust gas.
The membranes are mounted in the cam cover, where the two small covers are located approx above exhaust valves. The membranes just allowed fresh air to enter the exhaust. Exhaust gas was blocked by the membranes (CSR) or by the two small covers (LTDs).
That circuit is completely separated from air contained in the motor itself.
You may block that “canal” and everything should still work fine with all the other components coming from a B-model.
Maybe cutting a thread in it and close it with a screw and copper ring can be a solution ?
Cheers, Michael
