i don't want to discuss the pros or cons with dexcool vs the green stuff...

what i do want to do is flush out the dex REAL good, and replace with the green. i've done this on two previous 95 Z's, and no it doesn't eat holes in anything.

i've seen shoebox's radiator flush page, but i'm open to suggestions on how to do a more thorough flush without having to take it to a rad shop.

any ideas?

 

You can buy chemical flush agents at the auto supply stores if you want. The basis for the flush and refill writing of mine was taken from the factory manual and they don't mention anything about any chemicals. Unless you have some gunk or scale that just won't come out, I would think that running enough water through the system until it looks clear would suffice.

I would be sure that any agent you added to the system was compatible with aluminum, since the radiator and heads are made of such.

 

Also pull the knock sensor on the block to drain all of the coolant out of the block.

ZMAN

 

thanks for the pointers, guys...i appreciate it!

the last couple times i've done this (on my two previous Z's), there has been a "silt" to come out when i flushed the rad, so i wanted to make sure that it would all be removed (if this is the case on my new car). i don't know if this silt was due to a lack of it being changed in a timely matter, or if the dexcool just tends to do that over time.

the chemicals don't sound like a bad idea, but i will definitely check on the aluminum compatibility. otherwise, this could make for an expensive flush.

i guess i'll take off the thermostat and the knock sensor to make sure the block gets flushed. what about any silt that could possibly be in the block? do you just empty the rad/block of the existing coolant, then fill with water/chemicals and run it till the therm opens? then i'd have to wait for cool-down to empty and fill up. can i run it w/o the therm so that it's flowing as soon as it's on, rather than wait for 180 degrees?

travis

 

You could run it temporarily without the thermostat as long as you kept careful watch on the temp. You could also leave the block drains open (thermostat out and housing put back on), close the radiator drain valve and run water into the radiator to circulate it all they way through the block.

 

good idea...thanks so much for the "quickies", shoebox

i did a variation of that last time...i left the radiator drain plug open and ran tons of water straight into the rad...i didn't have the therm off at the time, though...it was a little weird since (i'm assuming) the system wasn't pressurized. when the therm opened and the water in the block mixed with the water in the rad, it was crackling and gurgling like you wouldn't believe...i was worried i'd end up warping the heads or something...also, i didn't know if the coolant lubes any of the bearings in the wp, etc...probably beginner concerns, but with the costs of doing business w/ LT1's, i couldn't afford to risk it.

travis

 

By temporarily, I meant for like a couple of heat and cool cycles or just running it in the driveway-not any extended driving.

Coolant does provide some lubrication to the water pump as well as corrosion protection that is very important for the aluminum.

 

well, at least i was on the right track with this...hopefully w/ your tips, i'll be able to finish this without too much trouble

thanks!

travis