Coolant change question
Thread Starter
Racer
Joined: Nov 2006
Posts: 297
Likes: 26
From: San Jose California
Coolant change question
I changed the coolant again and carefully measured the amount of old coolant that drained out. I measured only 8.7 quarts after jacking the rear up and removing the thermostat. The manual says the coolant capacity is 12,6 quarts. This means 30% (3.9/12.6) of the old coolant was retained after a "complete" drain. How do you get more old coolant out. I know I could do repeated flushes with water, but then I'd have many gallons of contaminated water to dispose of. There has to be a better way. What is it?
Thread Starter
Racer
Joined: Nov 2006
Posts: 297
Likes: 26
From: San Jose California
I don't have 30% of the old oil in the engine or 30% of the old fluid in the trans after I change them. I filled my engine with oil starting dry (after a rebuild) and it took LESS than 1/4 quart more than a normal oil change so at LEAST 6/61/4 (>96%) of the old oil comes out (if you jack up the rear and let it drain awhile) I'll bet the trans fluid (manual trans) drain efficiency is about the same. A mixture of 30% old coolant plus 70% new fluid is equivalent to a complete change of new fluid after 1 1/2 years. That's NOT efficient.
Tech Contributor
Joined: Oct 1999
Posts: 41,037
Likes: 9,798
From: Charlotte, NC (formerly Endicott, NY)
I flush/refill with water/flush the engine a couple of times until the water coming from the drain runs clear. Then I add in the proper amount of coolant to get a 50/50 mix and top off with water. You will get about 4 gallons of waste fluid.
Bill
Bill
Le Mans Master
Joined: Feb 2003
Posts: 6,682
Likes: 144
From: Memphis Tennessee
Safety Car
Joined: Sep 2000
Posts: 3,570
Likes: 420
From: Taildragers rule! USA1
I don't have 30% of the old oil in the engine or 30% of the old fluid in the trans after I change them. I filled my engine with oil starting dry (after a rebuild) and it took LESS than 1/4 quart more than a normal oil change so at LEAST 6/61/4 (>96%) of the old oil comes out (if you jack up the rear and let it drain awhile) I'll bet the trans fluid (manual trans) drain efficiency is about the same. A mixture of 30% old coolant plus 70% new fluid is equivalent to a complete change of new fluid after 1 1/2 years. That's NOT efficient.
Just do it more often.
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