I may be over thinking this and end up being made fun of due to being paranoid, buut...

Picked up some chemical coolant flush. The previous owners on the rex are rather well known at this point for half-assing stuff on this car. I don't trust the coolant seals much (Don't expect to get a lot of driving out of the current engine) due to this. Will running said chemical coolant flush cause any issues with the coolant seals?

 

I can't exactly answer that question, and for that i appologise.. but me personally, when i bought my fc the coolant in it was nasty brown, i simply drained the radiator, and drained the motor... i actually just removed the radiator and flushed it out with water, then i flushed the motor out with water real good, hooked it all back up and filled it with coolant, its looked pretty clean ever since..

 

I've not really heard much of a "Chemical Coolant Flush". I'm guessing it's just water and a hose but that's just how I do things. If you don't trust the seals then I would just tear the engine apart now but then again, that's how I would do things.
Read the chemical and make sure it doesn't have any sort of things that end in "ine" like "Gasoline, Benzine, Fluourine, etc." since those will eat your seals away. "ols" are good.

What's wrong with a hose and some water to flush the system out? It's a mess but it's fun! Anti-freeze does weird things to your hands and fingerprints!

 

Ehh, http://www.prestone.com/products/coo...Treatments.php - Super Coolant Flush. Working on getting the coolant system completely clean, after replacing all hoses/thermostat/water pump/etc.

 

the chemicals are supposed to break down deposits, but how does anyone really know if it works? you would have to tear down the engine right after to see the effectiveness. if you flush a few times it will probably be good enough until you rebuild, then you can clean the coolant passages thoroughly.