Hi folks,
I ordered and replaced the two cowl vent ducts - which were practically nonexistent in my car from heat and deterioration. So all I had left were the the two big openings. It was an easy job that required a stubby Philips screwdriver. My old clamps were in good shape so I reused them. What I was happy to see was that the new ducts angle downward and are tapered at the end. So that water can get out but next to no fumes can get in. The new ducts appear to be of some silicone rubber material but I am not 100% sure.
Of course one should address the root problem and correct any fumes from coming from the motor, but that is sometimes easier said than done.
I repaired my cracked exhaust manifold again - this time I let the mixture cure for 48 hours at room temperature instead of starting the vehicle to fast cure from the heat. We'll see how long it lasts this time.
