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I'm replacing my lower radiator hose, and want to remove all the coolant from the car. The radiator is drained, but I'm not sure where to drain the coolant from the water jackets in the block. There are two bolts, one on either side, about one inch above the oil pan flange, both angled downwards - are these the ones I want? This is a mid 70's era 350.
When I have the chance, I often replace them with new brass plugs, available at most auto parts stores. Easier to replace "just in case" than when a steel plug rusts in place.
Vice-Chairman (West), Michigan Chapter NCRS
71 "deer modified" coupe
72 5-Star Bowtie / Duntov coupe. https://www.flickr.com/photos/124695...57649252735124
2008 coupe
Available stickers: Engine suffix code, exhaust tips & mufflers, shocks, AIR diverter valve broadcast code.
They're not bolts; they're 1/8" NPT pipe plugs and, yes, these are the plugs you want to remove to drain the block. Basically, if you drain the block and open the radiator petcock, you'll drain the vast majority of the coolant from the system.
An often-encountered problem, though: very often these block drain plugs will be very difficult to remove. This occurs for a variety of reasons, including corrosion .
DO NOT use a 12-point socket, or you'll have good odds of rounding off the heads of the plugs - use a 6-point socket. Don't be surprised if nothing happens when you remove the plugs - you may have to poke an awl or screwdriver into the hole to break loose the crud that's accumulated in the bottom of the water jackets.
Thanks John. I did use a 6 point socket, and had none of the trouble I was expecting to encounter after reading the related horror stories on this board. The plugs backed out easily, after which the coolant flowed right out, no visible corrosion or gunk in the liquid or on the plugs. I will count myself as fortunate!
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