C4 Coolant Flush
 

Hello,
What is the simplest way to drain and flush a C4 LT1 Cooling system? I am willing to put a "T" in the right line and back flush...etc. I also assume that I can put in some Prestone type Radiator / Cooling System Cleaner....then flush again and refill with Green Juice.
Any adivse or suggestion or reference to a good website will be appreciated.
Thanks,


'95 Coupe / 27,000 Miles / 6-Speed / New Chrome C5 Wheels and New Tires

RE: C4 Coolant Flush
 

Welcome to the site Rick. Just wanted to let you know I moved this post to the C4 section, where you will probably get a faster response to your question. Good luck with your coolant flush.:D

RE: C4 Coolant Flush
 

The way we flush coolant systems at my shop is to take the upper radiator hose loose from the radiator,drain water from radiator, then fill radiator up with clear water til it comes out the open neck. Then start the car and leave the radiator cap off. Keep the hose handy with water turned on and when the engine reaches operating temp and the t-stat opens, it will start pumping water out the upper hose. Keep pumping water into the radiator until you get clear water coming out of your upper hose. Now, when you put the cool water back in, the stat will close, so you need to do this several times. It's messy and get a lot of water in your driveway, but thats the only way, and in my opinion, the best way to flush radiator as over the counter flushes you buy leave residue in you coolant system. After you get the clear water, drain system, button everything back up and install you antifreeze and water. [8D]

RE: C4 Coolant Flush
 

Rick, The shop manual for my '94 describes the cooling system flushing proceedure as follows. Carefully remove the rad fill cap from the rad surge tank when the engine has cooled ( allow pressure to release before fully removing cap). Open rad drain cock located at bottom of the right-hand radiator end tank. This will allow you to drain the rad only. You also have to drain the engine block. To do this, you must remove the two knock sensors ( located behind metal shields, on lower right and left-hand side of block). Removing one sensor will drain only that side of the block. You must remove both. Allow to drain completely. You can find the knock sensors on either side of the oil pan. If the coolant is discoloured, refill the system with water, run the engine until thermostat opens and fluid circulates. Repeat the drain proceedure. You may also want to remove the overflow bottle to drain and wash out. Fill system with correct coolant. For DIY, it helps to have the front wheels up on blocks. Make sure you are in a well ventillated area as the coolant vapours can be nauseating. Be kind to your environment and dispose of the old fluid safely. Good luck,

RE: C4 Coolant Flush
 

I know this is a really late response to this post, but the LT-1 has a very unique cooling system flow and therefore filling procedure. Anything you would ever need to know can be had by e-mailing Scott Mueller @ scottmueller@compuserve.com. He will provide you with the most detailed information I have ever seen on the LT-1 cooling system.

Regards