When I started this restoration my engine wasn't locked up b I t pretty darn close. Previous owner let it sit for 20-25 years with coolant on it. Needless to say the waterpump was pretty much all rust. I tore everything off the block took the Block mostly apart, soaked it in crud kutter, power washed, flipped it, drained it and repeated. Put it back together had good pressure so I replaced radiator, water pump, I think everything that attaches to the engine is new. I've ran it a few time, but haven't driven it, still working on some other bugs. But checked my coolant level and it appeared to have debris in it so I drained it and this is what I found. How concerned should I be? Should I disconnect the radiator and run the car with a hose cycling water thru it? Any help us appreciated.
And I guess, now that I think about it, I should probably pull the oil pan. Can't assume that crap is only in the coolant chambers right? Or would it just be in the coolant chambers? When I had the engine apart, the cylinders were nice and smooth, sealed good and had good pressure.
Rust never sleeps. There is no direct connection between the water jackets and oil system, so don't worry about that. But I guess there is still flaky rust in the system that is coming loose as you run the engine. Yes, I would go back to flushing and maybe add a cleaning agent. I use Cascade dishwashing detergent. Just don't let it sit too long as it is so aggressive it may find weak spots in your radiator. It also is harsh on aluminum so the timing cover may be attacked. The water pump is new so it should be OK. Just let it get good and hot, cool down, drain, and flush, flush, flush.
I actually had a great end to the fishing year. I took my Grandson, and my Daughter, out on separate trips, and loaded up on Bluefish each time. There was a huge school of Bluefish hanging around my area for several weeks. We banged them every trip. Then the hurricane sat offshore and slammed the coast with high winds, rough seas, and tons of rain. The fish left town, and it has been quiet ever since. I need to bring the boat home. That means the convertible has to go back in the garage for a while. Over the Summer I got the roll bar to fit, made some reinforcing plates for the floors, and I was about to weld the plates in place when my oxygen hose popped. I ordered a new hose set and I have been waiting weeks with no delivery. You know, years ago, Prestone used to sell a two-part cooling system cleaner. It was awesome, cleaned the most horrible junk out. The silver colored double-ended can had an acid cleaner that you left in for a day or so. That scoured the system down to bare metal. Then the other end of the can was a neutralizer to get the acid out and you flushed away the rest of the gunk. It worked beautifully. It has not been available for many years, that is why I use the Cascade as it works almost as well. Baking soda works as a neutralizer. But as I said, it works so well, any leaks like in the radiator will be opened up too. These are Bluefish. Teeth like razor blades, gorilla muscles, and can bite through steel leaders. FUN!