coolant flush/
Safety Car
Joined: Aug 1999
Posts: 4,249
Likes: 3
From: Grovetown Georgia
It's really easy to do, after jacking it up and placing the Vette on stands, I drained the coolant by removing the lower radiator hose. (I was changing the radiator so I had to remove the shroud before doing this). After it was drained, I replaced both hoses with new ones and refilled it from the tank up top. Probably the easiest thing to do on the Vette.
Team Owner
Joined: Oct 2000
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From: Fort Knox, KY
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I remove the thermostat, open the radiator petcock, then use a 6 hp (or higher) Shop-Vac with reverse thrust/blower capability to force the coolant out of the system using air power.
You don't have to remove the knock sensors, plus it completely evacuates the heater core and water galleys around the block, too.
You don't have to remove the knock sensors, plus it completely evacuates the heater core and water galleys around the block, too.
Last edited by onedef92; Aug 5, 2010 at 01:01 PM.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
I dumped the coolant in the radiator. Pulled the passenger knock sensor to dump that side of the block. Then pulled the oil cooler hose from the driver side to dump that side of the block. I had to take a screw driver to poke in the hole for the knock sensor to remove crud buildup.
Ran water through the thermostat opening. Also ran water through one of the heater hoses to flush the heater core. Closed it up. Filled with distilled. Let it get to operating temp. Then dumped the radiator and block. But next time I'd skip dumping the block again and just do the radiator.
But then I'd refill the radiator with distilled. Run to operating temp. Dump the radiator. Refill/repeat another time. Then dumped the radiator. Then fill with straight antifreeze. I believe the 89 is 14 quarts. So, I dumped in 7 quarts of straight antifreeze. Then if I needed to add anymore, I filled with distilled. Closed it up, ran to operating temp and burped it.
Ran water through the thermostat opening. Also ran water through one of the heater hoses to flush the heater core. Closed it up. Filled with distilled. Let it get to operating temp. Then dumped the radiator and block. But next time I'd skip dumping the block again and just do the radiator.
But then I'd refill the radiator with distilled. Run to operating temp. Dump the radiator. Refill/repeat another time. Then dumped the radiator. Then fill with straight antifreeze. I believe the 89 is 14 quarts. So, I dumped in 7 quarts of straight antifreeze. Then if I needed to add anymore, I filled with distilled. Closed it up, ran to operating temp and burped it.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
I remove the thermostat, open the radiator petcock, then use a 6 hp (or higher) Shop-Vac with reverse thrust/blower capability to force the coolant out of the system using air power.
You don't have to remove the knock sensors, plus it completely evacuates the heater core and water galleys around the block, too.
You don't have to remove the knock sensors, plus it completely evacuates the heater core and water galleys around the block, too.
Instructor
Joined: Jun 2010
Posts: 134
Likes: 0
From: Holladay Utah
The only downside to that I can see is it probably won't remove any crud that could be hanging around the bottom of the block. Which is why it would be good to at least once pull the drain plugs so you can wash out any crud at the bottom. But if you then maintain it from there on, you probably won't have to worry about crud build up. Especially since the antifreeze nowadays is low silicone.
Safety Car
Joined: Jan 2004
Posts: 3,759
Likes: 8
One thing is you may want to be careful and not get the clutch wet on the compressor. On a different GM car I have with the Harrison compressor. When I flushed the coolant, the clutch got a little wet. I didn't think anything about it. I got hung up on something and had to wait a couple of days before I could start it up again to finish flushing it with distilled. And I noticed the clutch was smoking and hanging up some instead of just spinning as I had it on full heat. It melted the clutch connector. So, something must have rusted is my guess.
