350 with 90 miles since rebuild.
While changing out a badly scored oil pump from failure to prime the oil system at initial startup (no age limit on rookie mistakes. I read that somewhere), I found a tiny bit of beautiful green ethylene glycol in the oil pan. The #8 spark plug is showing the telltale sign of antifreeze contamination and it actually rusted after a day on the work bench, while the other 7 plugs did not.
I removed the two intake manifold bolts at the rear near the #8 cylinder, put some high temp RTV on the threads and torqued them down. I drove the truck for 40 miles with new plugs and the #8 showed more evidence of antifreeze on it.
What would be a good course of action for me to follow to find out the source of the leak?
