coolant flush?
Thread Starter
Advanced
Joined: Jun 2004
Posts: 68
Likes: 0
From: north haven ct.
coolant flush?
hey fellas......i have a 95 lt1.....changing the coolant, this weekend . i need to know the easiest way and where the hell is the drain plug for the radiator....thanx guys
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The radiator drain plug should be at the bottom right corner of the radiator just above where the hose attaches. It's plastic and it does not come off, just turn until coolant runs out.
To get all of the coolant out and do a proper flush, the knock sensors should be removed. They are at the bottom of the block at the center. There are sheet metal heat shields to remove. I think a 21 or 22mm socket is needed. They are not the easiest thing to remove but that's the method according to the service manual. There is a write-up in the Tech Tip section about building a tool to flush the coolant.
When you refill, the system takes about 2 gallon of coolant and 2 gallons of distilled water. I believe the 95's have Dexcool so replace the ooolant with that. Don't go with the universal coolant or change to the green coolant. Not worth the possible trouble mixing the different types.
When you fill the system, open the bleed valves; there is one on the thermostat cover and IIRC, one on the bottom of the TB where the bypass hose attaches. As you fill the system, watch for coolant coming out in a steady stream, then close them. The service manual says to pour in the coolant first and then fill with distilled water, but thats for an already empty system.
Fill the expansion tank to the lip and start the motor. Watch for the level to drop and when it does, keep filling. Keep an eye on the coolant temp. If it hits 230-240, kill the motor and let it cool down and start again.
You should remove the overflow tank in the right side front well and clean it out. When the refill is done, add a 50-50 mix of coolant and distilled water to the proper mark.
To get all of the coolant out and do a proper flush, the knock sensors should be removed. They are at the bottom of the block at the center. There are sheet metal heat shields to remove. I think a 21 or 22mm socket is needed. They are not the easiest thing to remove but that's the method according to the service manual. There is a write-up in the Tech Tip section about building a tool to flush the coolant.
When you refill, the system takes about 2 gallon of coolant and 2 gallons of distilled water. I believe the 95's have Dexcool so replace the ooolant with that. Don't go with the universal coolant or change to the green coolant. Not worth the possible trouble mixing the different types.
When you fill the system, open the bleed valves; there is one on the thermostat cover and IIRC, one on the bottom of the TB where the bypass hose attaches. As you fill the system, watch for coolant coming out in a steady stream, then close them. The service manual says to pour in the coolant first and then fill with distilled water, but thats for an already empty system.
Fill the expansion tank to the lip and start the motor. Watch for the level to drop and when it does, keep filling. Keep an eye on the coolant temp. If it hits 230-240, kill the motor and let it cool down and start again.
You should remove the overflow tank in the right side front well and clean it out. When the refill is done, add a 50-50 mix of coolant and distilled water to the proper mark.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Originally Posted by c4cruiser
I believe the 95's have Dexcool so replace the ooolant with that. Don't go with the universal coolant or change to the green coolant. Not worth the possible trouble mixing the different types.
Thanks
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
Originally Posted by Atok
My '95 doesn't have Dexcool....it's filled with the green stuff. Does anyone know for sure if GM filled the '95s with Dexcool from the factory? Maybe someone changed mine to the wrong stuff which would BITE.
Thanks
Thanks
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
If the coolant is the ethlyene glycol (green) coolant, stay with that. Don't go back to Dexcool. Mixing the two coolants should not be done.
If the 95's did come with Dexcool, there should be some sort of sticker that said the coolant fill was a long-life coolant and "Dex-Cool" or something like that would be on the sticker. That's the GM trade name for the reddish-orange long life coolant.
If the 95's did come with Dexcool, there should be some sort of sticker that said the coolant fill was a long-life coolant and "Dex-Cool" or something like that would be on the sticker. That's the GM trade name for the reddish-orange long life coolant.
