I am going to be installing my 22" re-cored radiator in front of my daily driver slant. I was wondering if there were any suggestions on how I could clean the block before putting the radiator in? I know I can just hose it out (after removing the thermostat) but any ideas beyond that? I really don't want to remove freeze plugs.

Should I try and flush the system with the existing radiator in it? Or not bother and just do a block flushing? I will be using the Tefba filter in the upper radiator hose.

Lastly, is there a part number for a 180 degree Stant SuperStat?
Also what cap should I be using? I will be using the overflow tank.

You can remove the starter and the freeze plugs, use various rods and lengths of straightened-out hanger to scrape up and dislodge the rusty mud accumulated in the block, then flush it forward and out via the lower radiator hose. Failing that, you're pretty much stuck relying on chemical cleaning methods which are messy and difficult to do properly with the engine assembled and in the car.

Stant SuperStat 180° is 45358.

What cap to use depends on what coolant you're using. With conventional coolant, do not use less than a 14-pound cap, 16-pound with A/C. If you're running waterless coolant like I am, the cap needn't hold any pressure at all (a 4- or 7-pound cap, in practice) because the stuff won't boil at any temperature your engine can actually reach. See here, here, and here for discussion and here for the company's website. It is costly but beneficial -- not only in terms of engine-cooling performance, but when there's no water in the cooling system there's no corrosion, and when there's no pressure in the cooling system all the hoses, solder joints, seals, and gaskets are under a great deal less stress. Works well fer me.

Smile and nod politely with no intent to follow the advice of those who advocate using a low-pressure cap (e.g., 7 pounds) with coolant that contains water.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Thanks for the info Dan!

I will not be running waterless coolant during this time --- I actually already read those threads you linked via searching before you made this post. I will be running G-05 antifreeze mixed 50/50 with distilled water. I will not have A/C but I will be living in San Diego where it's on the warm side (shouldn't matter I don't think). Should I just look for a Stant radiator cap that's 14-16lbs then, and compatible with an overflow tank (I also read the threads on the different types of caps)?.

Yep, get a 16-pound double-seal cap, preferably the partial-pressure variety. I like Chrysler p/n 5207 9880AA.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Not to high-jack this thread but I have to make the quick comment of, Dan I love your new sig! It's so true!

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Annabelle: 1970 Dodge Dart Hardtop
1991 Nissan 240sx (sileighty) Lots of mods
1974 Dodge Dart *Wrecked*