SLO247 1,713 Posted October 13, 2018 Anyone know what thread the coolant drain plugs are either side of the cleveland block? They are different to the oil gallery plugs, tried that already. 1 CHESTNUTXE reacted to this Share this post Link to post Share on other sites
bear351c 10,270 Posted October 13, 2018 Never been able to get them out.! I'm guessing.......1/4" or 5/16" UNF. 2 CHESTNUTXE and 351XD_Fairmont reacted to this Share this post Link to post Share on other sites
351XD_Fairmont 604 Posted October 13, 2018 Yeah if you get them out tell us how, I tried everything short of drilling them out and only managed to twist the heads off Share this post Link to post Share on other sites
SLO247 1,713 Posted October 13, 2018 I got one out no worries, the machinist did the other as it was locked solid. I wanted to get the most out of the hot tanking. Need to know the size to get replacements. He drilled and used a snap on ezy out type of tool. Share this post Link to post Share on other sites
SLO247 1,713 Posted October 14, 2018 Seems to be 1/2" unf, seems a bit odd to me though that there is little available in that size other than sump plugs. Share this post Link to post Share on other sites
SLO247 1,713 Posted October 14, 2018 1/4 NPT, makes more sense! Share this post Link to post Share on other sites
bear351c 10,270 Posted October 15, 2018 I guess. NPT was used on oil fittings, etc.... Maybe the Clevo had a water gauge on the side, in a different model Ford.? Share this post Link to post Share on other sites
351XD_Fairmont 604 Posted October 15, 2018 So did it end up being 1/4" NPT or 1/2" Unf? Have seen pictures my uncle or someone took from an old car show of a hotrod with a gauge there before Share this post Link to post Share on other sites
SLO247 1,713 Posted October 15, 2018 Is indeed 1/4 NPT, turns out they are measured differently so very close in size. 1 351XD_Fairmont reacted to this Share this post Link to post Share on other sites