Not Enough Coolant Recovered

adamsanders

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I have a question regarding a coolant flush/change I am in the middle of. So my coolant was very nasty when I drained it. Unfortunately I didn't measure how much came out originally but I assumed I would get 7-8 gallons (using block drains+radiator drain) as I have read on OB many times. I have flushed about 5 times now and started roughly measuring the amount of water I was draining each time (using block drains + radiator drain) and it is only about 4-5 gallons. I am catching at least 80-90% of the water and I am letting it drain until its just a drip. What could be causing such a low capacity? To flush, I am filling the radiator, running the truck to operating temp., and then draining it. Also, the water started getting quite a bit more clear after all the flushes.
 

Thatoneguy

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I'm not sure what is causing it, but if you're getting clearer with each flush I wouldn't worry about it. But when you do fire it up in between flushed, I wouldn't just run it until it warms up and then flush again. I would run it, and go for a good drive to make sure everything is circulated nicely and then drain. You'll probably get more of the crud and old coolant out that way.

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Thewespaul

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Could be that something is clogged like your oil cooler, or that you may be parked on an incline
 

79jasper

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Where are you draining from? Sounds like just the rad. Pull the drain plugs in the block, too.

Mike


Excuse the dumb question, but are you draining the radiator as well?


Unfortunately I didn't measure how much came out originally but I assumed I would get 7-8 gallons (using block drains+radiator drain) as I have read on OB many times. I have flushed about 5 times now and started roughly measuring the amount of water I was draining each time (using block drains + radiator drain) and it is only about 4-5 gallons.



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adamsanders

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More likely is that you are getting a bubble when you fill it back up, so you aren't getting the full amount in it.

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How would I remedy this? It is true that I filled the radiator up put the cap on and didn't open it again til I drained it. I didn't check the level after I cranked it. Could a bubble be responsible for 2-3 gallons of capacity?
 

Thatoneguy

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How would I remedy this? It is true that I filled the radiator up put the cap on and didn't open it again til I drained it. I didn't check the level after I cranked it. Could a bubble be responsible for 2-3 gallons of capacity?
Fill the rad, and before you out the cap on start squeezing the upper and lower hoses. That'll help burp the system. And then while the motor is still warm fire it up and get to to operating temp. You'll probably see bubbles coming out of coolant and then the level will drop with each bubble. Add more accordingly.

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BrianX128

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How would I remedy this? It is true that I filled the radiator up put the cap on and didn't open it again til I drained it. I didn't check the level after I cranked it. Could a bubble be responsible for 2-3 gallons of capacity?

Yeah kinda when your draining the whole system. I'm doing my water pump now and last night I filled the truck with distilled water and when I went for a ride my mechanical and factory gauges were going bananas as everything was getting to it's home in there. This morning I went out and as I opened the radiator cap I figured it would need topped off but I added 1 3/ 4 gallons of distilled water. I'm draining mine again tomorrow morning and getting my coolant and distilled 50/50 but I'm sure I won't get all 4 gallons of coolant and distilled in first try. Gotta get it hot enough to open the thermostat and make the truck lean different ways to get the air to come to the top.
 

Thatoneguy

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79jasper

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Yup. Otherwise it can be a chore.
And you risk overheating if you try to "work it out."
Just a note, typically temp sensors only read when there's coolant actually touching it. So the head could be way hotter.

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Thatoneguy

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coolant temp sensors work like a meat thermometer. If you just hold it out in the warm air its not gonna read accurate. But if you actually touch it to something hot, it reads accurate.
 

icanfixall

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Probably an air bubble. Try driving the passenger side up on a block to lift that side of the engine. That way you make the trapped air seek the high point. Remember the thermostatis lower than the head so air can become trapped. Another way is to remove the heater hose so you get coolant flow out of the passenger side head. My driveway is angled so the front of my rig is always slightly pointed uphill. No air bubbles ever. Lastly the vacuum coolant system is the best way to refill the coolant.
 
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