Ahhh, the 300-Six ..the engine you just about can't kill:
1) My brother knew a guy who had been running a pickup with a 300 I-6 for years w/o any coolant in the system. Now, this was an older gentleman and his trips were mostly around town ..but he'd go to neighboring towns now and then. My brother gave him a price to fix it, but he didn't come back for another year or two...LOL. He didn't care it was dry. My brother said it was probably w/o coolant for years. He replaced most of the cooling system, plugs, etc.
2) We hired a young apprentice in 2010-ish. His previous job was he and another guy were the ones who would "kill" engines on vehicles traded in from the Cash-For-Clunkers program. Remember that? If you bought a more fuel efficient vehicle that met certain parameters, you could get a Gov't rebate (lets not debate that). The idea was to kick-start car sales/economy. Most of the vehicles traded in were older, high-mile worn-out pickups or larger SUV's (classic vehicles weren't part of the prog). I asked him what the hardest to kill engines were and he right away shot back, the Ford 300-six. He and his partner did the 'killing' out behind the dealership. He said they were never able to kill a single one of them! They poured in the plaster-like mix and would rev and rev it and they'd never die or even start smoking he said.
Eventually they'd give up and just fill in the necessary paperwork that they completed the process. Hopefully the new Dodge/Chrysler I-6 will end up being that robust.
I once owned a GM I-6 in a mid/late 70's pickup with a manual trans, which was a lot stronger and smoother than people might think. A distant decendent of the Stove-bolt-six. One of the last yrs of their I-6's. I was impressed with it. That bugger was a real honey, esp with the manual. Lot of space in that engine bay. Yeah, a straight-6 with a manual is kind of a nice combo in a basic truck.
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