Do you prefer to drain from radiator petcock or lower radiator hose?

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Took me 10 years to find this space
Apr 14, 2006
Los Angeles
I was all set to flush.
Most coolant came out during multiple hose replacement, I pulled the engine block drain. Another gallon came out.

I filled up with tap water, ready to drive to local garden hose for flush.
Put the key in after a month of replacing hoses, and of course....dead battery.

I'll charge up tonight.
Meanwhile, I still can't find the damn radiator drain plug (petcock) was just going to drain from lower radiator hose.
Any reason why petcock is better? Worse?
Yes, tell me your stories.
@DARKNESS What;s the easy way to take off lower radiator hose. Mine are new.
I have pliers locked on the clamp, so that's out of the way.
But I pull on the hose, and no budge.
Is there a trick?
(for the old hoses, I used a hook and/or cut them off...but these new ones have zero miles)
I used the petcock just the other day during a coolant flush. I had to remove the metal splash pan but it was pretty straightforward (no tools needed for the petcock, just hand tight).

It did make a bit of mess, even with a 5 gallon and 3 gallon bucket under there to catch the coolant. I don't know if its more messy than removing the lower radiator hose but it's a lot easier to open and close when flushing the system.
seems to me I recall slipping a rubber hose on the petcock, and neatly draining into a bucket. but maybe it was my 40?
Easiest is to place a bucket under the lower hose. Place a plastic trash bag over and around the hose. Under the hose and let it drain in the plastic bag which is in the bucket. Easy peasy and zero mess.
If you've got the patience, just crack open the drain cock a little bit and let it dribble out slowly into one of those big square, low storage totes.

A small piece of larger hose can be propped up near the drain cock to help guide the trickle.

I don't remember how I got it off. I think I just squeezed the clamp, moved it off, then yanked the hose.
I just can't empty it through the petcock without making a mess, but that said I don't think I've emptied it any way without making a mess.
The hose method will drain most of the system in about 10 seconds, by far the fastest method.
So I ended up pulling the lower hose, as the petcock is a bear to get too.

Even draining everywhere during heater hose replacement, there was appox. a gallon of coolant still inside the engine block when I drained it.
Hose. Crud builds up in the bottom of the radiator, petcock is slow and crud jams up behind it, or just sits in the bottom of the rad. Twist the hose and pull it off, the speed that the water is dumped out (Rad cap off) means a lot of crud comes with it. When done, slip hose on and fill with water and run the engine a few minutes and pull the hose again, get that crud out!


^n Yep, petcock is in a stupid location and it drains in a stupid spot. Like many things on our 80's Toyota must have assigned the job of its design/location to either a gnome sized person and/or an idiot.

To remove hoses I use a nice tool from snap-on that has a pointy (but not sharp) end and its bends allow it to be used to insert between a hose and the inlet/outlet metal. You then work it around to break the 'seal' that has formed over months/years as the rubber hose has fused to the metal. Makes removing hoses a breeze.


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