I got one more dumb question. I'm gonna try to drive the ranger to the cabin tomorrow, once I get out of the city I can take gravel roads all the the way, it just takes longer, the wife is gonna follow me just in case something goes wrong.
So, if loosen the radiator cap like halfway to the first stop, would that help relieve some pressure while I drive or will it start leaking coolant or blow the cap? It's a little over 1 hour drive on gravel roads, just trying to make sure I get there safely and with a running truck, if something happens I have a friend ready to bring a trailer but I rather not go through that. Thanks guys..
Drain some coolant from radiator, so its down 2"s or so.
You can leave the cap loose, rotated to first(and only) stop, so no pressure builds up in the system.
Coolant still expands when heated, this is where the pressure comes from, and why you need to leave some room at the top of the radiator for the coolant to expand into.
Vehicles ran like this for years, no pressure in the system, and also with pressure and no overflow tank, just like current Degas setups you just leave room in the system for coolant to expand.
50/50 coolant will boil at 230degF with no pressure in the system, engine normally runs at 190-200degF so no issue there, BUT inside the heads coolant will be 10-15deg hotter, still enough of a margin but if you see any signs of temp gauge climbing slow it down and let it cool down
With pressure 50/50 boils at 260degF
Water boils at 212degF(sea level) with no pressure, so straight water would not be a good idea with loose rad cap
As you go up in altitude any fluid boils at a lower temp, water and 50/50 boils at 2degF less for each 1,000ft
so at 3,000ft elevation water would boil at 206deg, coolant at 224deg, -6 degF, with no pressure