odd issue with coolant passages

[Sendero]

Have to take my 440 block for machining, looks like a broke ring in one cylinder (#4 ) .While draining the coolant with no radiator attached, I remove the lower block driver side plug to drain it further. Nothing came out - but the head and block passageways still had coolant. Seems like I have a blockage somewhere in the block. I took the heads off and still the same; coolant at the top of the block; not all passages but the front on both sides. I then had the car/block tilted (highside /front) and still the same. Coolant is green with very little "rust". Assume a rare condition. Anyone run into this? Car has less than 1k miles since full rebuild from a professional shop. Needless to say I am pissed. Carlisle was all arranged and the shops around here say 6-8 month wait.

[472 R/T SE]

Was the block bored previously?

[Sendero]

Yes. Rebored in 2005 to .30 over.

[b5blue]

  A few months ago I cleaned up a used 440 and after pulling the expansion plugs found a lot of rust crap built up at the bottom of the water jacket. I flushed it out with a rig with a 1/4" brass tube that fits the end of a garden hose but found bunches more after raking the bottom of the water jacket with coat hanger wire through every possible coolant hole and expansion plug opening. I'm sure the 440 had never been cleaned but the amount of rust that cleared AFTER I'd thought it was flushed was remarkable. The trick was scratching all over the water jacket over and over to bust up and loosen crap stuck where you can't see.

[John_Kunkel]

  It's not unusual for sludge to build up behind the block drain plugs, just dig around with a sharp tool to break through the sludge wall and it'll drain.

[Sendero]

Hi all and thanks for the feedback. The feedback indicates that it could have been the front water passengers in the block that could not flow leading (eventually) to a cylinder scoring. The orig. rebuild (over .30) was 13k miles and 2006 year.  In 2019, I had the  bottom end redone and new cam put in - less than 1k miles. Cam and lifters look fine.

[cdr]

Thats why I run a Gano upper radiator hose inline filter screen, old block will still have rust chunks EVEN after a hot tanking cleaning

[Sendero]

Thanks CDR. Never thought that AFTER hot tanking the rust clumps could still be in there. Learned something new.

[70 sublime]

Thats why I run a Gano upper radiator hose inline filter screen, old block will still have rust chunks EVEN after a hot tanking cleaning

How often do you clean the screen out ?

[cdr]

Thats why I run a Gano upper radiator hose inline filter screen, old block will still have rust chunks EVEN after a hot tanking cleaning

How often do you clean the screen out ?

After I ruined the new radiator with small rust particles , I replaced the radiator & put the gano screen in, I put a small magnet in the screen section, I checked & cleaned it after about 500 miles the 1st time & then about every 1k miles, as time & miles went there was less & less in the screen, last time I checked it after about 5k miles it had almost nothing in it, I still keep in the upper hose just in case , you can see it in the pic