How to fully drain antifreeze

croderique

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Hello, I’m working on the 1964 Chrysler 300 “383”. I have drained the antifreeze, but can’t get more than about 2.5 gallons out, even running the engine for a few minutes.
The Shop Service manual says it holds 16 quarts + 1 for heater. That would be 4.25 gallons.
I have drained 2.5 gallons then used a cleaner, ran for 30 minutes, drained another 2.5 gallons. Repeat, and repeat again without a cleaner. Still not clear water coming out as it is mixing with the water left over. How do I get the rest of the fluid out? I did not remove the thermostat since you have to move the AC compressor and yes using distilled water.
Any hints would be appreciated.
Thanks
Chuck
 
Flush each component separately until they're running clear -

Flush the heater core at the connections to the firewall (make sure the temp lever is on hot to open the valve) until it runs clear

Flush the radiator at the upper hose and run the bottom into a container until it runs clear

Flush the engine at the upper hose connection - remove the thermostat - and out the lower hose connection into a container until it runs clear.
 
Remove the plugs in each side of the block. They are pipe threads. They had 9/16” hex when new, use a 6 point socket so you don’t round them off. You may need to poke through a layer of rust for them to drain once removed.
lots of coolant stays on the block so this will get it clean much quicker.

remove heater hoses and flush the heater core.
 
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In order to drain the block, you can either remove all the freeze plugs , wash out all of the accumnulation in the block water passages, and replace the plugs, which might be advisable for the age of the car AND the fact that all of the "accumulation" will be at the rear of the block, which is the lowest part of the engine in the car. Or possibly remove the drain plugs in the side of the block and see what comes out.

That coolant capacity spec is for a dry engine block and such, not one which has had coolant in it.

The 26" radiator usually can hold just past 9 quarts on our '66 Newport 383 with factory a/c. Which puts that system down to -34 degrees F in coolant protection.

ONE issue with using "a cleaner" is that it can remove the rust on the back of the freeze plugs, which then makes for thinner metal, which can be more prone to leak after that.

If just doing "a rinse" with the engine at idle, open the radiator drain plug and put a water hose into the filler neck, adjusting the water flow to keep the radiator full. When the water is consistently clean, then remove the lower radiator hose and empty the radiator. Turn off the water hose. After the radiator has fully drained, then reattach the hose (or install a new one), and refill the radiator with appropriate full-strength coolant. Usually 2 gallons and a bit more. Install the radiator cap and run the engine, let it cool fully and adjust the coolent level to factory spec. Then run the engine to get things fully up to temp and re-check when fully cold. Adjust as needed and then re-check a week or so later after several drives.

Enjoy!
CBODY67
 
Hello, I’m working on the 1964 Chrysler 300 “383”. I have drained the antifreeze, but can’t get more than about 2.5 gallons out, even running the engine for a few minutes.
The Shop Service manual says it holds 16 quarts + 1 for heater. That would be 4.25 gallons.
I have drained 2.5 gallons then used a cleaner, ran for 30 minutes, drained another 2.5 gallons. Repeat, and repeat again without a cleaner. Still not clear water coming out as it is mixing with the water left over. How do I get the rest of the fluid out? I did not remove the thermostat since you have to move the AC compressor and yes using distilled water.
Any hints would be appreciated.
Thanks
Chuck
Remove the radiator cap, remove the bottom hose off the engine, make sure the thermostat is open, open your heater controls, put your mouth over the top of the radiator cap and blow as hard as you can! Sorry, I couldn't stop myself!
 
One trick I've used to drain the heater core is to put a wet/dry vacuum on one heater nipple.
 
Remove the plugs in each side of the block. They are pipe threads. They had 9/16” hex when new, use a 6 point socket so you don’t round them off. You may need to poke through a layer of rust for them to drain once removed.
lots of coolant stays on the block so this will get it clean much quicker.

remove heater hoses and flush the heater core.
Agree. Especially for getting flush water out of the engine block.
Example of drain plug at engine block (please ignore temp core plug)

DSC00458ps.jpg
 
Remove the plugs in each side of the block. They are pipe threads. They had 9/16” hex when new, use a 6 point socket so you don’t round them off. You may need to poke through a layer of rust for them to drain once removed.
lots of coolant stays on the block so this will get it clean much quicker.

remove heater hoses and flush the heater core.
Those pipe plugs are usually in there really tight, like rusted tight. Once using the 9/16"hex, what do you use to twist them out? It seems that area of the block is susceptible to cracks and I would want of course to avoid that.
 
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I use 1/2” drive breaker bar and a name brand quality 6 point socket. No extension is best to keep the socket square on the plug.

Get the socket squarely on there and tighten it first to break it loose. Then take it out. Machine shops remove these plugs all the time before the hot tank/cleaning process. You are not going to crack the block doing this by hand

yes that area is susceptible to cracks when water freezes inside.

Name brand quality tools: USA made older craftsman is Ok, or use MAC, Matco, Proto, Snap-on, etc
 
I use 1/2” drive breaker bar and a name brand quality 6 point socket. No extension is best to keep the socket square on the plug.

Get the socket squarely on there and tighten it first to break it loose. Then take it out. Machine shops remove these plugs all the time before the hot tank/cleaning process. You are not going to crack the block doing this by hand

yes that area is susceptible to cracks when water freezes inside.

Name brand quality tools: USA made older craftsman is Ok, or use MAC, Matco, Proto, Snap-on, etc

I hear you and I am glad I didn't hear "use an impact driver, etc. in that area".
 
In order to drain the block, you can either remove all the freeze plugs , wash out all of the accumnulation in the block water passages, and replace the plugs, which might be advisable for the age of the car AND the fact that all of the "accumulation" will be at the rear of the block, which is the lowest part of the engine in the car. Or possibly remove the drain plugs in the side of the block and see what comes out.

That coolant capacity spec is for a dry engine block and such, not one which has had coolant in it.

The 26" radiator usually can hold just past 9 quarts on our '66 Newport 383 with factory a/c. Which puts that system down to -34 degrees F in coolant protection.

ONE issue with using "a cleaner" is that it can remove the rust on the back of the freeze plugs, which then makes for thinner metal, which can be more prone to leak after that.

If just doing "a rinse" with the engine at idle, open the radiator drain plug and put a water hose into the filler neck, adjusting the water flow to keep the radiator full. When the water is consistently clean, then remove the lower radiator hose and empty the radiator. Turn off the water hose. After the radiator has fully drained, then reattach the hose (or install a new one), and refill the radiator with appropriate full-strength coolant. Usually 2 gallons and a bit more. Install the radiator cap and run the engine, let it cool fully and adjust the coolent level to factory spec. Then run the engine to get things fully up to temp and re-check when fully cold. Adjust as needed and then re-check a week or so later after several drives.

Enjoy!
CBODY67

This all recalls very clearly the fun I had last autumn cleaning out a block with the passenger side cooling jacket nearly full of debris. If removing the core expansion plugs, then use a drain snake to help get all the mineral deposits which tend toward the rear cylinders. Those help! Long flexible, STIFF bottle brushes and such, not excluding small wire wheel brushes turned by a drill all help get the hard stuff off the inner walls, sundry brass tools et cetera ALL help folks get that jacket as clean as possible for an engine in situ. Beyond this point, one should just pull the motor, break it down and vat it.

Good organic acid flushes can help with mineral deposits. You so rightly warn of the danger of leaks arising as the "crud" also served as PATCHING!

Its all worth it once the system is clean though. My 65/66 383 runs VERY nice and cool as a consequence of religious cleansing.
 
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I use 1/2” drive breaker bar and a name brand quality 6 point socket. No extension is best to keep the socket square on the plug.

Get the socket squarely on there and tighten it first to break it loose. Then take it out. Machine shops remove these plugs all the time before the hot tank/cleaning process. You are not going to crack the block doing this by hand

yes that area is susceptible to cracks when water freezes inside.

Name brand quality tools: USA made older craftsman is Ok, or use MAC, Matco, Proto, Snap-on, etc

All this stuff is unpleasantly familiar. Yes, NEVER USE CHEAP ASIATIC ERSATZ POTMETAL TOOLS!

I've purged my collection of such junk metal and donated it. I don't feel right asking money for that crap. If not forged in North America, or Europe, I don't use the tool anymore. The old stuff is MARKEDLY SUPERIOR to what sells at flea market tool stores now.
 
One trick I've used to drain the heater core is to put a wet/dry vacuum on one heater nipple.

Regular part of my coolant draining routine. Good wet/dry vacs can get a LOT of fluid out, though by NO means ALL of it.
 
Hello, I’m working on the 1964 Chrysler 300 “383”. I have drained the antifreeze, but can’t get more than about 2.5 gallons out, even running the engine for a few minutes.
The Shop Service manual says it holds 16 quarts + 1 for heater. That would be 4.25 gallons.
I have drained 2.5 gallons then used a cleaner, ran for 30 minutes, drained another 2.5 gallons. Repeat, and repeat again without a cleaner. Still not clear water coming out as it is mixing with the water left over. How do I get the rest of the fluid out? I did not remove the thermostat since you have to move the AC compressor and yes using distilled water.
Any hints would be appreciated.
Thanks
Chuck
Hi Chuck,
Please let us know if you try removing the block drain plugs and if that alleviates the problem.
Good luck! Ben
 
I opened the two threaded plugs on the block and punched a hole through the silicone the previous owner/Chrysler mechanic had put there. Out came almost 2 gallons of fluid. I also ran a reverse flush on the heater core. In both instances the water is almost clear now. I’m doing another flush now. Looks like problem solved. It does take over 4 gallons of fluid like the Service Manual shows.
Thanks for the help.
Chuck
 
I opened the two threaded plugs on the block and punched a hole through the silicone the previous owner/Chrysler mechanic had put there. Out came almost 2 gallons of fluid. I also ran a reverse flush on the heater core. In both instances the water is almost clear now. I’m doing another flush now. Looks like problem solved. It does take over 4 gallons of fluid like the Service Manual shows.
Thanks for the help.
Chuck
Awesome!
 
Hello, I’m working on the 1964 Chrysler 300 “383”. I have drained the antifreeze, but can’t get more than about 2.5 gallons out, even running the engine for a few minutes.
The Shop Service manual says it holds 16 quarts + 1 for heater. That would be 4.25 gallons.
I have drained 2.5 gallons then used a cleaner, ran for 30 minutes, drained another 2.5 gallons. Repeat, and repeat again without a cleaner. Still not clear water coming out as it is mixing with the water left over. How do I get the rest of the fluid out? I did not remove the thermostat since you have to move the AC compressor and yes using distilled water.
Any hints would be appreciated.
Thanks
Chuck
there is a block drian u can remove if u dare i nevered worried about it after flushing i ran te water untill it ran clear then drained te radator to get more i removed the lower hose then replaced if closed the rad drain & refikked the cooling sysren]
 
one other note you need to consider- when this car was produced, and all vehicles prior to 1985, antifreeze was labeled "permanent". due to several factors, the companies that make antifreeze reformulated the mixture so that the product was no longer "permanent". with the product now available, it is only effective for 2-5 years and has no lubricant for the water pump seal in it any more. i would recommend purchasing a water pump lubricant (water soluable oil) to install in the cooling system.
 
Thanks. Yes I did put in a rust inhibitor and water pump lubricant. Funny about the “permanent “ antifreeze. The previous owner died about 12 years ago and the car just set after that. No telling how long before that it was changed. Probably never. It took several flushes to get it clean.
 
The word "permanant", in this situation, refers to the fact that Ma Mopar was filling our cooling systems with glycol based coolant. In years prior, antifreeze was alcohol based. The alcohol would boil out and leave the system unprotected. Glycol does not boil out and is therefore "permanant". As previously noted the rust inhibitors and water pump lubricants are not permanant. I remember "years ago", before I had a driver's licence, alcohol based antifreeze was still available in auto parts outlets. Lindsay
 
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