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So I've got a cracked manifold in a pretty easy to get to spot. I'm curious if I can get the truck warmed up and use brazing rod to seal it up enough to stop the leak temporarily. Would the manifold get hot enough to melt the rod or would it have to be welded as a permanent fix? The main reason I'm worried is because it's before the O2 tricking it and giving me a CEL and MPG is terrible. I'd prefer not to have to replace it because 1: new isnt available and 2: I'm not sure how well the bolts on the bottom will come loose without breaking so I cant remove it to have it welded. I've fixed stamped steel headers with brazing rod before but Idk about cast iron.
My biggest fear is there was only the one crack when I first saw it. Driving the truck more have appeared. I'm worried welding or sealing the holes won't really help but make more cracks appear.