Proper way to perform coolant flush?

[DJ 2501]

Ok I'm doing a hg in my car in a week and need to know how to get all the coolant out of my engine and heater core. The reason I need a complete flush is because (not knowing any better) the guy I got the car from had been using water because the bgh was overflowing the overflow. Once I learned the hg was blown I continued to use water so I wouldnt throw money away on coolant.

Once I get the hg replaced Im putting toyota red in there but I want all the water out. I already see brown (rust?) in my overflow from the cooling system so I know the water in there is causing damage. Im just hoping the block hasnt been hurt too bad by the water being in there.

 

[ben1984j]

There is a drain plug on the side of the block. When you put it back in make sure to torque it to spec and use thread sealant. You shouldn't need to "flush" the water out with coolant, if that's what you're saying...the minerals and ions in a few drops of tap water aren't going to give you problems, putting in several quarts of it is what's a bad idea.

I was gonna say the brown in your overflow was due to exhaust gases mixing with the coolant (common on BHG's), but then remembered you've been running water instead of coolant...I don't know if the discoloration would happen with water (maybe someone else on here does) but it's something to think about. I can't imagine rust doing enough damage to cause a visible change in the color, but who knows how long this has been going on...

By the way, you shouldn't still be driving it...should have stopped as soon as you learned the HG was blown. Actually, the previous owner should have stopped as soon as he learned it was blown, little late for that though haha...

 

[DJ 2501]

There is a drain plug on the side of the block. When you put it back in make sure to torque it to spec and use thread sealant. You shouldn't need to "flush" the water out with coolant, if that's what you're saying...the minerals and ions in a few drops of tap water aren't going to give you problems, putting in several quarts of it is what's a bad idea.

I was gonna say the brown in your overflow was due to exhaust gases mixing with the coolant (common on BHG's), but then remembered you've been running water instead of coolant...I don't know if the discoloration would happen with water (maybe someone else on here does) but it's something to think about. I can't imagine rust doing enough damage to cause a visible change in the color, but who knows how long this has been going on...

By the way, you shouldn't still be driving it...should have stopped as soon as you learned the HG was blown. Actually, the previous owner should have stopped as soon as he learned it was blown, little late for that though haha...

Yea Im not driving the car anymore it's been parked since I found out 100% it a bhg. Theres more than just some water in the system, theres only water in the system which of course is why I'm concerned about the damage to the block. That and I have no idea how long the po ran the car with straight water, Iv had it for a month now.

 

[lewis15498]

Considering both the previous owner and yourself drove around with a BHG I would be doing a complete rebuild. Unless that is your looking forward to hearing knock when your bearings go.

Also im pretty sure the brown in your overflow is caused by the mixing of coolant or water and oil. Never heard the exhuast gas thing before.

You are supposed to mix coolant with water, having water in your system isnt going to hurt anything. On the other hand, I'm assuming what you have in there is not water but brown mucky oil/water mix, which you do want to get out. You can have the machine shop hot tank the block and or head to clean it good inside and out.

Ninja edit: Just saw your in ohio, which means you cant be too far from Rich (sip racing) He knows his shit and does machine work. I'd be contacting him if I were you. rschubert69@sbcglobal.net He also has a misc vendor thread here.

 

[DJ 2501]

The bhg isnt mixing coolant with oil or oil with water. I dont even think the hg is actually blown, I just dont think its sealing because the po threw an hks on stock block surface with no machining. I guess Im one of the lucky ones because all thats happening is the exhaust is entering the cooling system under boost. I know there is no coolant is the oil because I have checked it a million times. Im going to be putting a stock hg set on there for now. I just needed to know how to get all the water out of the block so I can put toyota red in there after the hg replacement.

 

[ben1984j]

I'm surprised you haven't heard of the exhaust gas thing Lewis I've read about it at least a few times...
http://www.supramania.com/forums/showthread.php?t=23664
http://www.supramania.com/forums/showthread.php?t=106288
http://www.supramania.com/forums/showthread.php?t=89565

I did say I wasn't sure if the discoloration would happen with water as opposed to coolant. Everything I've found about the subject only mentions coolant reacting with the exhaust gases, so I guess there's no reason to think it would happen with water. Yes, the brown is most likely rust then (since you said you already checked the coolant for oil). But even if it's not the cause for the discoloration, exhaust gases are still getting into the cooling system - that's what's been causing coolant (or water) to get pushed out the overflow. Sorry to whoever thought my post was "unhelpful" but it answered his original question and nothing was wrong...I was just raising a side question I wasn't trying to present it as fact...

Also (to the OP) when you said you needed a "complete flush"...I misundertood and thought you meant "flushing" all traces of the tap water out. But you just meant draining the whole system, of course you do need to do that...my bad. Good luck with it

 

[DJ 2501]

This is what the coolant(water) looks like, its not oil.

See the rust colored dust on the intercooler from it overflowing. Its a brown powder that wipes off.

The water in the res is clean and clear, its just the inside of the overflow that is discolored.

 

[DJ 2501]

Ok I drained all the water out of the rad and block this morning and left both drain plugs off to let any moister out. I'll be starting to rip the head off to replace the hg, might start a build thread (even tho my build will be a slow one) just so I have a place to show everything I've done to the car.

EDIT: Also talked to Rich at SIP Racing, he's about 20 mins away from me. He gave me a great price on the head/block work and he can hook me up with a gasket the right size when the work is done. He also said he can get the head/block within the RA Spec needed to seal a metal gasket. Thanks for the referral I didnt want to take this to my usual machine shop because I dont think they could do the work right.