The factory set up had the "hot start valves" (actually fuel bowl vents) connected to a charcoal canister located on the right inner fender behind the headlight or near the right hood hinge depending on the year. My '72 had it behind the headlight, the '70 behind the hinge.

The large fitting on top of the front carb goes to the suction side of the charcoal canister.

If you no longer have the charcoal canister (probably not effective anymore anyway if original equipment) there will be no ill affects by routing the hoses as Rhys suggested.

The small fitting on the rear carb goes to the distributer diaphram. Depending on the distributer, some people leave this connected, some don't. I have it connected as intended without problems. Can't remember which model dist. I have right now though.



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'60 544 x89k, '68 220S 94k, '70 145S 130k, '72 144E 245k, '86 745T 145k

Hi Nick;
The hot start valves can be left as is, or vacuum line may be used and the hose routed to someplace away from the exhaust manifold, near the front suspension. The large fitting on the top can be plugged, as can the small vacuum fitting on the bottom. The vacuum retard module on the distributor should be left alone and not connected at all.