I know there's a drain plug at the bottom of the radiator, but how to you drain it so that everything out?

I'm installing my new rad 2morrow, so I would like to know how to drain the entire cooling system

Thanks in advance guys

 

Flush with water

 

before or after new rad?

care to elaborate?

i've never installed a rad b4, so it's gonna be a first for me, so I don't really know how to flush it either.

 

1. Make sure car is completely cool or rad cap is cool so hot coolant won't spray
2. Drain coolant
3. Plug radiator
4. Fill radiator with water and leave radiator cap off and let engine idle for 10-15 mins
5. Drain water
6. Install new radiator
7. Fill with 50/50 mixture of coolant and water

 

There is also a bolt on the left side of the header heatshield that can be used to drain the block of all coolant.

 

theres also a drain bolt on the block, its to the left and behind the exhaust mani.

 

there is a hose where the coolant goes from the rad to the engine and a hose where the coolant goes from the engine back to the rad...stick a garden hose in the rad hose that goes into the engine and turn the water on, the water will come out the other hose and you will essentially flush the entire system not just the rad

 

awesome, thanks a lot guys!

 

"Probably not, unless you have some sort of catch container that is wide and very short. My big round oil drain pan/container combo won't even fit underneath my bumper.

And the method for COMPLETELY flushing the radiator listed above isn't really correct. First drain the coolant from the radiator thru the drain plug, then disconnect the lower radiator hose from the radiator to let coolant drain out of there. Put the radiator hose back on.

Next locate the coolant drain bolt on the engine block. On B and D series engines it's behind the exhaust manifold/header, slighly towards the tranny end of the block. It's a BIG bolt, 19mm I believe, hard to miss. Remove that. Have a large container ready, because it will come GUSHING out. After it finishes draining, replace the bolt.

Now comes the tricky part. Remove the lower radiator hose and coolant temp sensor from the thermostat housing and then remove the housing w/ the thermostat. One of the housing bolts is pretty difficult to get to, so have some wrenches or a swivel socket joint handy (I can't remember what I used). Put the housing back in w/o the thermostat and reconnect the lower hose.

Now remove the upper radiator hose from the radiator and point it towards your drain bucket. Stick the garden hose into the top of the radiator where the upper hose connects and run the water. The remaining coolant in the block will be flushed out through the upper radiator hose. Keep the water running until the fluid coming out of the upper hose is clear.

Reinstall the thermostat and coolant temp sensor and all hoses etc. Fill the radiator w/ a 50/50 mixture of coolant and water (Honda pre-mixed, or Prestone and distilled water, do NOT use Xerex or Peak as it contains silicates which can damage the radiator). You will have to pour it in SLOWLY as it tends to bubble up and spurt out of the filler hole while you pour it in.

Once the coolant reaches the base of the filler neck, run the engine with the heater slider set to HOT. Continue to run the engine until it fully warms up and the radiator fan comes on. The upper radiator hose will also become hot. After this the coolant level in the radiator should have dropped since the thermostat opens and allows coolant into the block and the heater core. Shut off the engine, and continue to fill the radiator until it get to the base of the filler neck.

Locate the bleed bolt where the upper radiator hose attaches to the cylinder head. Loosen this bolt and let the coolant flow out until it flows out steady w/o bubbles. Squeeze the upper radiator hose to help get any remaining air out of the system. Continue squeezing the upper hose until no more bubbles come up at the base of the filler neck, and continue to add coolant as necessary to keep the level at the base of the filler neck.

Remove and wash out the coolant overflow tank, fill it to the proper level, and you're done!

Wow I didn't know it would be this long, but that's how it's done. If I've left out or messed up any steps, please chime in. "

 

hahahah I wrote that ^^^ I was just about to go look for that post where I typed all that.

The key to flushing out the block is removing the thermostat and reinstalling the empty housing while you flush it. Otherwise the closed thermostat will not allow anything to flow past it.

 

hehe i was wondering who wrote that. I just copied the text and put it in the notepad.

 

here is a good detailed tutorial http://student.ucr.edu/~ohe02/

go to DIY in the menu and go to coolant flush

 

i really appreciate the responses, and I already replaced my rad yesterday...but where the hell is the drain bolt??? Am i retarted? Sorry for the large pic, but I need to show the detail. The bolt on top of the bleeder bolt leaks oil, so that can't be it...



hmmm...the red plug seems to be connected to my block heater, so I guess that it? Oh well, I guess I'll drain it next year...


Modified by whiteGSR at 2:28 PM 6/22/2003

 

^^

it's right below between the cylinder 4 and cylinder 3 exhaust primaries roughly 8-12 inches below it.

 

its the only 19mm bolt on the front of the block.

 

where the block heater is... that is where the drain would normally be... i have never seen one of those in person yet but i figure u can take it out... just unplug it first... afterall that is the standard drain bolt

 

I just drained...and filled with distilled water, let it run with the heater on, and did that a few times,
that is after i drained the block, and pumped water in the rad

 

DETAIL your motor man... if it was clean you might be able to find something big like a 19mm bolt..

 

that one bolt hidden in the dark

 

You responded to a 19 year old dead thread.

Thread closed.