HOW TO Flush Coolant Protect opti

[kenmack]

Recently did a complete engine coolant flush,which included pulling the "knock sensors"in the bottom of the block.
I was paranoid about the two bleeders up beside the thermostat and directly over the opti spark.
I tried every thing to build a drain with tinfoil over the waterpump and away from the opti.Couldn't do it.Hard to drain "uphill"
I finally took about 4 shop rags and stuffed them down the back of the waterpump and directly under the bleeders.
They actually absorbed quite a bit of coolant,even though I was really careful to limit the amount of "bleeding" required.
The rags worked like a charm,it would take a lot of fluid to actually soak them and drip onto the opti housing.

 

[LT4man]

I have drained, flushed & refilled my LT4 engine in 2001 and 2006. I have NEVER used the air bleeder screws.

Run your engine. Keep radiator cap removed. When coolant drops in metal reserve tank, add coolant slowly. Install cap. Take for test drive. Upon returning home, remove cap slowly while engine is running. Make sure coolant level is up. Top off coolant in white plastic reservoir tank near radiator.

No mess, no fuss!

SAVE THE

 

[Tuna]

I used rags like you did under the bleeder without any problem. You don't need to open the bleeder much for air to get out and when coolant starts to come out, close the bleeder. The rags are sufficient for that.

 

[compyelc4]

Lt4man is correct. You do not have to use the bleeders. That is what your overflow container is for. LT1's will get rid of trapped air themselves in short order. At least I've never had to use the bleeders.

 

[kenmack]

You may be correct

Lt4man is correct. You do not have to use the bleeders. That is what your overflow container is for. LT1's will get rid of trapped air themselves in short order. At least I've never had to use the bleeders.

Thanks for the input guys
I've done a lot of flushes as well and yes you can just top up and use the reservoir as place to purge air
Note that I said I removed the knock sensors in the bottom of the block,this I believe purges the entire cooling system as opposed to a typical flush which pushes a lot of coolant out but leaves a large percentage for instance at the bottom rear of the block.The process I used also introduces air to a lot of places in the block that take a long time to bubble out and therefor I think the bleeder screws are a very handy place to release the air.I wasn't interested in a typical flush,because I didn't know how old the coolant was.Most people don't remove knock sensors but it ensures almost total removal of old coolant.Besides GM wouldn't put 2 bleeder screws if they served no
purpose.