just like the title says guy's , you got any secret concoctions that'll clean out all the dain old casting sand in a flatty ??? the one in question is once again the 52's . been tinkering with it trying to get her right . sometimes she's fine then ........... this time i let her sit at a fast idle watching the temp gauge and a kitchen thermometer stuck in the radiator neck and all of a sudden comes a mud pie from hades outta the neck . it's plugged up internally with this crap and i'm letting it cool then gonna open up the drain , pull the top hoses off and fill the engine from there on both sides , stick the hose in it and let it flow ... or am i looking at trouble or do you have another way ???????

 

The engine is tilted to the rear, so park on a steep downhill section. If you want to pull a water pump, that is the best way to get the junk out (one side at a time). You can also stick a 1/4" copper pipe connected to a hose back in thru there to stir things up. It sounds like you've got a lot of the mud loose, you just need to get it out. Some folks have drilled and tapped a drain at the rear of the block, but I'd be REAL cautious about doing that, the water jacket is up higher than you'd guess.

PS -- you need to pull the thermostats to pour water in the top

 

Remember that the two sides of the V8 are NOT connected except in the radiator - Also the passenger side temp sender measures the temp in that side while the drivers side sender is a on/off unit (Hot or Not)

 

tstats are out ross. just a washer in 'em . took one hose off at a time after darn near filling it , added some generic radiator flush , fired it up put the hose in the hose with water going full tilt and went back and forth like that { p.s. ran the car as suggested for a bit with the flush in it } till we got clear water then opened up the bottom drain on the radiator { and yep parked downhill / nose first in the drive , i can be smarter than i appear sometimes LOL !!!!!!!! }and kept doin it till i had clear water period . pulled the bottom hoses and refired it to get it all outta the motor then . and the top hoses off also . put it back together with fresh water and a lil' anitfreeze in case we had to pull it down again , fired it up and she was sitting at idle and me modulating the accelerator upon occasion and while the temp gauge went to the top she wasn't hot , just barely to the touch and you could pull the cap off without anything coming out from under it at all under pressure . so we wait a couple of days , recheck the timing , change the carb { got a blown power valve and such } and fire it up and go for a drive then if it passes refill her with a 50 /50 mix . got impatient waiting for the miracle cure ya know ....... LOL !!!!!!!!!!!!!!!!!

 

I like to put the engine at a fast idle, open all drain pet***** (some flathead have them in the block too), put a garden hose in the radiator so it fills at the same rate the pet***** are draining, let everything go until the water runs clear. Then take compressed air and blow back into the pet*****. Makes a heck of a mess, but knocks crud loose.