5,9 magnum hard crusties in the thermostat housing?

so I decided to take apart the coolant system on a 5.9 magnum in my 65 coronet.
I kept finding coolant in my drip tray in front. so I wind up adding water periodically when I take it out.
about half a gallon each time to top off the radiator.
The overflow tank is always empty.
but I have changed the coolant a few times over the last 4 or 5 years due to fan issues, making me pull the rad out.

It has been a few years since I changed the hoses out, and I cobbled the hoses to make it fit, so it couldn't hurt to replace some of the ends with the silicone replacement elbows I have been seeing, for a better fit.
i have some of those steel accordioned tubing to make some odd runs.
I noticed the insides of them were rust colored even though the coolant is green. even when I watch it circulate.

I pulled the top hose off and noticed inside the thermostat housing some weird build up. like I would call it piles of stuff on the side walls of the tube.
I went to pull them off but they were hard crusts, and eventually broke off, but in doing so, crumbled up.

I haven't pulled the zinc anode I installed yet.
But was wondering if I should be checking something else?

Coolant came out orange when it started at the low point drain, but went green really fast.

Telling us exactly what that orange coolant is might help. I know the old Dexcool has issues chunking up in the presence of air in the system. You have a leak, so that might be it.

I just runt he green stuff and change it as needed. As often as you said you've changed that orange stuff you may as well just run the green.

no I only run green coolant.
I meant when I first opened the drain, it looked orange. then quickly went green as it was draining.

Was the buildup a whiteish tan color? That’s silica dropout from not changing the coolant often enough. It’s really the Achilles heal of conventional green which is other wise excellent. I try to use Zerex GO5 nowadays for that very reason.

some of it might have been tan or rust colored, but most of it was black.

No idea how I got it into my mind you said orange. Old age I guess, lol

I've never encountered what you describe, but I'm of the mindset that there's nothing new/different/peculiar about the Magnum motor that would create that. If it was me, I'd flush it good, refill it with quality coolant and forget about the mystery lumps.

Where do you live?

north texas, dfw area.

just wasn't sure. I didn't know if that long neck for the top hose had any known issues. I see they sell a dorman replacement. so thought it might be a known rust issue.

yeah, will flush it and see once I get all the other hose parts together.

Hi Andrew , those Block drains are Easy to pull , make sure you pull each side out , WHILE you are flushing everything . Poke a screwdriver & twist , and get all the Dex-Kool , green , Factory Orange and every other coolant that has NOT been Flushed in ages , Out . Ronnie

Rust (brown) mixed with green can look that way when draining. I bought my truck from a dealer and i know it had a leaking freeze plug that either the previous owner or the dealer put in stop leak. After i got it home i pulled the lower freeze plugs on both sides of the block. I then put some brass fittings together(so i could position the nozzle) to pressure wash out the block. You would be amazed at the curd at the bottom of the block. Since this is a Texas truck it may have been run with out antifreeze at some point. This may be something you could consider if you see rust coming out when you flush it.

Lots of minerals in the water. Corrodes aluminum workin overtime. Best to use distilled water.

I only use rodi water.
wife has an aquarium, so I piggyback off her system for water.

I was going to pull a block drain because I put a zinc anode in it. see how that is doing.
But will pull the other side now too, so I get a better flush.
Thanks for the reminder, wasn't even thinking about it.