70 Big block radiator replacement
Thread Starter
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
70 Big block radiator replacement
I bought a new DeWitts radiator last winter when they were on sale, starting to plan my work, replacing the radiator.
Is it easier/cleaner to remove the radiator support with the radiator still mounted rather than try to get the shroud out of the way, fish the radiator out from between the support and shroud?
The last time the radiator was out was when the body was off the car. I bought a new shroud, no desire to cut the shroud. I'd rather take more time taking things apart if needed.
I will have at least another pair of helping hands if not two others.
Is it easier/cleaner to remove the radiator support with the radiator still mounted rather than try to get the shroud out of the way, fish the radiator out from between the support and shroud?
The last time the radiator was out was when the body was off the car. I bought a new shroud, no desire to cut the shroud. I'd rather take more time taking things apart if needed.
I will have at least another pair of helping hands if not two others.
Burning Brakes
Joined: Apr 2013
Posts: 926
Likes: 2
From: Castle Rock CO
I have always thought it was easiest to remove the Fan assembly and fan shroud than move the alternator and power steering pump out of the way. I am getting ready to install a 4 core radiator into my 1977 next weekend and have thought about removing the hood also for easier access from the top.
What I am going to do is remove the fan then the fan shroud before I disconnect anything else then I will take off the hoses, disconnect the automatic tranny lines. I have a tranny cooler so I only need to disconnect one steel line and the other is a hose. Once the fan shroud is out of the way it should be easy to remove the radiator.
What I am going to do is remove the fan then the fan shroud before I disconnect anything else then I will take off the hoses, disconnect the automatic tranny lines. I have a tranny cooler so I only need to disconnect one steel line and the other is a hose. Once the fan shroud is out of the way it should be easy to remove the radiator.
Thread Starter
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
I have always thought it was easiest to remove the Fan assembly and fan shroud than move the alternator and power steering pump out of the way. I am getting ready to install a 4 core radiator into my 1977 next weekend and have thought about removing the hood also for easier access from the top.
What I am going to do is remove the fan then the fan shroud before I disconnect anything else then I will take off the hoses, disconnect the automatic tranny lines. I have a tranny cooler so I only need to disconnect one steel line and the other is a hose. Once the fan shroud is out of the way it should be easy to remove the radiator.
What I am going to do is remove the fan then the fan shroud before I disconnect anything else then I will take off the hoses, disconnect the automatic tranny lines. I have a tranny cooler so I only need to disconnect one steel line and the other is a hose. Once the fan shroud is out of the way it should be easy to remove the radiator.
Racer
Joined: Sep 2013
Posts: 284
Likes: 16
From: St Louis MO http://1972corvetterestomod.blogspot.com/
On my '72 big block car... I disconnected the shroud bolts and let it rest on the fan, disconnected the side support bolts and tilted it slightly forward, and then the radiator came out by itself pretty easily with me on side and my son on the other. Then the support came out by itself. Don't think I could've made it work with the radiator and support still connected together.
Racer
Joined: Sep 2013
Posts: 284
Likes: 16
From: St Louis MO http://1972corvetterestomod.blogspot.com/
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
I just installed a Dewitts in my 69 427. Removed the hood then unbolted the support and lifted the rad/support/ shroud out as a unit. It was a really easy job with no swearing and without the headaches of struggling with the shroud in the car and probably less time. You can also clean up all the parts outside of the car and install it back in as a unit.
Burning Brakes
Joined: Jul 2009
Posts: 1,240
Likes: 294
From: ESCONDIDO CA
2025 C2 of the Year ('63 and '67) Finalist - Unmodified
C2 of Year Finalist (appearance mods) 2019
Here are a couple of things I did on my 69 big block.
In an effort to gain more cooling, I removed the plastic (for lack of a better word) shroud. I was able to remove the fan then protect the radiator with a 1/4 material and work the shroud out of the car. It took a little prying but it can be done.
I installed an electric fan on the radiator. I wasn't impressed with the results still ran warm and I got a little nervous that the fan could for for one reason or another.
Dewitt's went on sale so bought one.
Yesterday was install day. Removed the electric fan, left the support in place because of the vintage air unit in front. Pulled the old radiator out with a little finesse. With that out, I layed the old shroud back in place (loose). I protected both sides of the new radiator with cardboard and was able to install it pretty easily. Did not have to disturb the radiator support or Vintage Air. Yes I did take the hood off but that's not hard either. So, turned out to be a lot eased than I thought.
Also, must say the Dewitt's has twice the fins of the radiator that was in the car. So I'm hopeful.
In an effort to gain more cooling, I removed the plastic (for lack of a better word) shroud. I was able to remove the fan then protect the radiator with a 1/4 material and work the shroud out of the car. It took a little prying but it can be done.
I installed an electric fan on the radiator. I wasn't impressed with the results still ran warm and I got a little nervous that the fan could for for one reason or another.
Dewitt's went on sale so bought one.
Yesterday was install day. Removed the electric fan, left the support in place because of the vintage air unit in front. Pulled the old radiator out with a little finesse. With that out, I layed the old shroud back in place (loose). I protected both sides of the new radiator with cardboard and was able to install it pretty easily. Did not have to disturb the radiator support or Vintage Air. Yes I did take the hood off but that's not hard either. So, turned out to be a lot eased than I thought.
Also, must say the Dewitt's has twice the fins of the radiator that was in the car. So I'm hopeful.
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Verdad Gallardo
Acct suspended by request 14 Aug 2014
Joined: Nov 2013
Posts: 22
Likes: 0
From: Dallas TX
1. Remove hood; drain coolant
2. Remove fan and hoses
3. Remove upper radiator brackets
4. Unbolt shroud and free it from support studs so it's loose but still behind the radiator
5. Unfasten receiver/dryer bracket from body/inner fender
6. Loosen lower core support bolts; remove remaing core support bolts
7. Gently tilt core support forward an inch or so being careful to not smash condenser or radiator into headlight vacuum motors. Consider placing cardboard in front of condenser or radiator to protect them.
8. Lift and remove radiator. While gently holding core support forward, wiggle the shroud and radiator around a bit to clear the a-arms and frame rails. Unless you have four arms, having a helper makes this a lot easier. Radiator comes out first, then shroud.
Even though written over 40 years ago, it's a good idea to read the factory service manual before tackling any job. Protecting the condenser with cardboard is my addition. Ask me how I learned this lesson.
Last edited by MarkEdmondson; Jun 29, 2014 at 12:37 PM.
Burning Brakes
Joined: Oct 2001
Posts: 911
Likes: 5
From: TN
1970 radiator removal
Having owned my 1970 since it was a new car I have removed the large radiator a few times.
Have never removed the hood to remove the radiator.
After draining the radiator I place a floor jack under the passenger side lower control arm and lift.
I then remove the two control arm nuts and tape the alignment shims from each location separately and mark the tape to identify their positions.
I knock out the control arm bolt closest to the engine and slide the control arm back away from the shroud.
Remove the fasteners for the fan shroud and lift it out from the passenger side.
Remove mounting attachments for radiator, disconnect the transmission lines, and coolant hoses.
Lift out radiator.
Always done this by myself, no help needed.
Still using original factory installed radiator.
I remove block coolant drain plugs to remove contained coolant in the block for complete coolant change.
Have never removed the hood to remove the radiator.
After draining the radiator I place a floor jack under the passenger side lower control arm and lift.
I then remove the two control arm nuts and tape the alignment shims from each location separately and mark the tape to identify their positions.
I knock out the control arm bolt closest to the engine and slide the control arm back away from the shroud.
Remove the fasteners for the fan shroud and lift it out from the passenger side.
Remove mounting attachments for radiator, disconnect the transmission lines, and coolant hoses.
Lift out radiator.
Always done this by myself, no help needed.
Still using original factory installed radiator.
I remove block coolant drain plugs to remove contained coolant in the block for complete coolant change.
Last edited by 70ZZ3 96LT4; Jun 29, 2014 at 06:04 PM.
Acct suspended by request 14 Aug 2014
Joined: Nov 2013
Posts: 22
Likes: 0
From: Dallas TX
Having owned my 1970 since it was a new car I have removed the large radiator a few times.
Have never removed the hood to remove the radiator.
After draining the radiator I place a floor jack under the passenger side lower control arm and lift.
I then remove the two control arm nuts and tape the alignment shims from each location separately and mark the tape to identify their positions.
I knock out the control arm bolt closest to the engine and slide the control arm back away from the shroud.
Remove the fasteners for the fan shroud and lift it out from the passenger side.
Remove mounting attachments for radiator, disconnect the transmission lines, and coolant hoses.
Lift out radiator.
Always done this by myself, no help needed.
Still using original factory installed radiator.
I remove block coolant drain plugs to remove contained coolant in the block for complete coolant change.
Have never removed the hood to remove the radiator.
After draining the radiator I place a floor jack under the passenger side lower control arm and lift.
I then remove the two control arm nuts and tape the alignment shims from each location separately and mark the tape to identify their positions.
I knock out the control arm bolt closest to the engine and slide the control arm back away from the shroud.
Remove the fasteners for the fan shroud and lift it out from the passenger side.
Remove mounting attachments for radiator, disconnect the transmission lines, and coolant hoses.
Lift out radiator.
Always done this by myself, no help needed.
Still using original factory installed radiator.
I remove block coolant drain plugs to remove contained coolant in the block for complete coolant change.
Thread Starter
Melting Slicks
Joined: Apr 2007
Posts: 3,189
Likes: 111
From: Tolland CT
I didn't find removing the hood or radiator support to be all that difficult. Having the hood off gave me more room to work. Having the radiator support and shroud out gave me access to frame cross member and front of the engine, allowed me to do some refreshing.
The radiator gave me a hard time removing it from the support. It was stuck to the seals. This would have been tougher to work on in the car with the hood on.
I now have the new radiator installed, everything together again. It wasn't that hard with another person to help with the lifting.
It can be done without removing the hood and radiator support but didn't strike me as being that much easier.
The radiator gave me a hard time removing it from the support. It was stuck to the seals. This would have been tougher to work on in the car with the hood on.
I now have the new radiator installed, everything together again. It wasn't that hard with another person to help with the lifting.
It can be done without removing the hood and radiator support but didn't strike me as being that much easier.
Team Owner
Joined: Jul 2004
Posts: 40,408
Likes: 792
From: Redondo Beach, California
[SIZE="5"]I'm planning on a 496/502 for my 70. Will this radiator be sufficient? I want an extra size radiator, since I plan on using 100% ethylene glycol coolant...no water. My 68 Corvette, my 95 Cadillac Seville, my 97 Thunderbird have no water in their radiators....pure ethylene glycol. Still have 50/50 Dextrol in the 08 Vette.
Acct suspended by request 14 Aug 2014
Joined: Nov 2013
Posts: 22
Likes: 0
From: Dallas TX
- Freeze protection is reduced. Pure ethylene glycol freezes at +10°F, while a mixture of 60% ethylene glycol and 40% water freezes at −49 °F.
- Heat absorption capacity is reduced. The specific heat of water is greater than ethylene glycol, meaning water absorbs more heat than ethylene glycol.
- Additive strength is impacted. The coolant manufacturer sets the concentration of rust inhibitors, anti-foaming agents and lubricants in their product to work best when diluted as instructed on the label.
Of course, this does not apply to pre-diluted coolant. Whatever product you choose (diluted or not), read and follow the label.
Last edited by MarkEdmondson; Jul 9, 2014 at 10:58 AM.