zoomad75
K5 Camper guy
Thanks for the info. The engine was in @zoomad75 truck running and driving about two weeks ago ha, so It has not been sitting very long at all. As for cooling, Im leaning towards electric. I have the big 6.2 diesel radiator and haven't looked into how big of a fan setup I can put on that. Being in Phoenix I want the most cooling I can get. I am aware of the broken manifold bolt, Rob told me about that when I picked it up. I have a plan to remedy it.
I'm a big fan of the KISS idea for the cooling system. This engine on a stock 350 size radiator and steel 7 blade fan would run hot at low speeds when ambient temps climbed above 90 degrees. I came home after the trip that exposed that weakness and stuffed in the biggest radiator GM put in these trucks which was the 6.2 diesel version. Combined with the correct shroud for that radiator and a 9 blade fan from a 2500 6.0 application and an HD fan clutch the cooling issues were fixed. I've personally seen this engine purring along in the Mojave desert at 10 mph with over 100 degrees of ambient heat and the temp is running below 180 degrees. Most of the time it ran at 160 at 90 degrees ambient or below. There were no electronics to fail. On the last trip I ran it on last month I never saw the gauge over 180. We saw high 90's to low 100's on the more southern part of our trip.
I'm old school in that thinking, but I've yet to see a problem with running a solid, basic, high capacity cooling system that has less possibility for failure. I haven't seen many electric fan failures at the dealership I work at, but I can say this I've seen less mechanical cooling system failures for sure. I'm not a fan of being deep in the desert and having cooling issues so the big radiator, fan and HD clutch might be a bit overkill for a 5.3, but it never ran hot in 3 years of hard use.