'74 Radiator Flush Question
Thread Starter
Intermediate
Joined: Aug 2021
Posts: 32
Likes: 3
From: Western Washington
'74 Radiator Flush Question
Hi all,
Doing my 1st radiator flush on my '74 today. Completed the process and am ready to drain the radiator for the final time and put in the coolant. Question: Do I just fill the radiator to the top or should I also put some coolant in the recovery tank? Wondering as there doesn't seem to be any min/max level markers on the recovery tank.
Thanks!
Doing my 1st radiator flush on my '74 today. Completed the process and am ready to drain the radiator for the final time and put in the coolant. Question: Do I just fill the radiator to the top or should I also put some coolant in the recovery tank? Wondering as there doesn't seem to be any min/max level markers on the recovery tank.
Thanks!
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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and rust and crap in there too....
its more important than draining the radiator as all that loose crap in there now because of the flush can clog the radiator
its more important than draining the radiator as all that loose crap in there now because of the flush can clog the radiator
Le Mans Master
Joined: Aug 2006
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From: mount holly NC
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Thread Starter
Intermediate
Joined: Aug 2021
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From: Western Washington
Team Owner
Joined: Jan 2007
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From: Southern Cal Ca
St. Jude Donor '22
that is not a flush.
it is a half coolant change.
there is a back flush using heater hose.
there are chemicals to loosen and dissolve crap, followed by complete system drain including block drain.
good luck
it is a half coolant change.
there is a back flush using heater hose.
there are chemicals to loosen and dissolve crap, followed by complete system drain including block drain.
good luck
Racer
Joined: Sep 2021
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From: Upstate South Carolina
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,116
Likes: 9,244
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I bought the prestone radiator flush, drained the coolant, added water and the flush chemicals. Drove it around for about 30 to 40 miles which was out to my brother house and back, then drained the radiator and block. I did this 3 times. Then when it was flushing clear I drained it fully and removed the radiator. Stuffed a hose and rag into the outlet side and back flushed the big rust particles out that may have clogged the tubes.
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Team Owner
Joined: Jan 2007
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From: Southern Cal Ca
St. Jude Donor '22
I bought the prestone radiator flush, drained the coolant, added water and the flush chemicals. Drove it around for about 30 to 40 miles which was out to my brother house and back, then drained the radiator and block. I did this 3 times. Then when it was flushing clear I drained it fully and removed the radiator. Stuffed a hose and rag into the outlet side and back flushed the big rust particles out that may have clogged the tubes.
Team Owner
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From: Redondo Beach, California
I've been using pure ethylene glycol in my 68 since about 1975. 1975 was when I had to replace the original factory aluminum radiator due to corrosion. I bought a new GM radiator and have used ethylene ever since. When I replaced the original factory engine with a ZZ4. the coolant passages of the original engine were rust free...they were coated with thin coating of the white silicate that's in anti-freeze.
Le Mans Master
Joined: Apr 2011
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From: Hermosa
Consider the environment you operate your corvette in if you choose to go 100% glycol. Below 5* F it's gonna freeze. Most of us would be fine particularly if you're not driving it in those temps. Glycol contracts when it freezes vs expanding like water.
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all of the stuff on today's store shelves are weak; make your own diy
https://www.corvetteforum.com/forums/c3-tech-performance/4594091-engine-block-coolant-capacity.html#post1604468383
https://www.corvetteforum.com/forums/c3-tech-performance/4594091-engine-block-coolant-capacity.html#post1604468383