Hello,

I've tried searching high & low and couldn't find anything about this .

I'm just finishing up a head gasket job on my truck & want to flush everything out of the cooling system without going through the rad.

I've got a brand-new rad so i really dont want to be sending all the gunk through it. i was wondering if icould simply hook a garden hose up to the inlet pipe, put a bucket under the outlet & pump water through the block & heater core (bypassing the radiator completely).

i don't know if this will work. i know i have to take out the thermostat but i don't know if i can push water through the pump without running the engine.

which brings me to my second question... Assuming this is even possible, should i run the engine when i do this?

 

That'll work!

 

That's the way to do it. Not while the engine is running though. Pull the thermostat out, stick in garden hose,and let the hose run. If you have compressed air,you can try to seal off the air hose and garden hose in the thermostat housing and pulse the air to agitate the crap in the bottom of the block.

 

I just did a search and found this thread. I am doing the exact same thing. Does this flush out the heater core too?

I have the radiator out, new one waiting, and flushing water through the block where the thermostat was (engine not running) Does this flush the heater core at the same time?

Should i pull the heater core hoses and flush w hose separately?

I will flush w/ distilled water before adding coolant.

Thanks

 

it will flush out your heater core if you have your heat turned on. Also, flush it both ways. And don't let it sit overnight after you do this. Flash rust will start from the water on the bare metal on the block. Then you'll be right back where you started. refill with coolant asap.

 

I did this last week successfully. I did not run the engine.
Also somewhere I read on firing up an enging after major work instead of using coolant just use water with a can of radiator anti-rust additive. This way if you do have a leak you wont get coolant in your oil. Once you are sure there are no leaks then drain and refill with toyota red.

 

Thanks for the gOod info.

Maybe i did not have enough pressure or something but i flooded the block with water at the thermostat housing and let the water run untill clear. Then because i just wanted to be sure i removed the long heater hose and hooked that up to the hose and then i got some more old coolant. So, maybe because the heater core and lines are more restrictive than the block, the initial flush did not get all the stuff? I did have the heater on (heater core valve open)

 

Another mystery is that i was only able to get a little more than 5 quarts in the coolant syatem. I filled as much as i could via the thermostat housing and sealed it up. Then i put in the rest of the 5 quarts.

I drove it to town and back (~10 miles) but she just does not want anymore. I thought the 22re will take nearly 9 quarts? Maybe i just need to work the air out. I hope so 'cause i put in 5 quarts straight stuff and i was going to put another 4 quarts of distilled water in to get the ratio right.

 

Always mix before adding, you never know how much it's going to take because you never know how much is still in there.

 

Yep, makes sense to me.

There must have been at least a couple quarts of water in there. That is why added straight coolant instead of 50/50 'cause i flushed with distilled water.

If i got 5 quarts of straight coolant in there then the rest must be water which makes 55/45 coolant/water.

I guess im alright. I'll just keep topping off with water.