2000 cherokee sport 4.0 with 179,000 miles
Went to flush out radiator (dirty brown rust colored coolant) I know cooling capacity is 3 gal. But when I drain either thru peacock on radiator or pulling lower hose , I only seem to get 1.5 gal. Of coolant ??
Is this normal ? I plan on replacing , radiator waterpump, thermostat. Just wanted to flush out before replacing
Btw, disconnected heater core hoses and flushed out separately

Any help would be great

 

Normal. There's a lot left in the block & heater core.

I recommend an old mechanic's trick: Add a quarter cup of Amway SA8 laundry detergent, and run it with that in there for a few weeks. If you don't have to worry about freezing temps where you are, just water and SA8, nothing else.

Then flush, rinse, and fill with coolant. Your cooling system will be squeaky clean.


Some folks say Dawn dishwashing liquid works, too. Dunno, haven't tried it.

You can find Amway dealers online.



By the way, it's a petcock, not peacock. Be careful with those - they can stick or break in a open position, forcing you to replace the radiator. Not fun. Best to just leave them alone, and drain by removing the lower radiator hose.

 

X2 about using the lower radiator hose, you would drain both the radiator and the engine block at the same time