DeWitts Radiator Installed
Thread Starter
Safety Car
Joined: Apr 2016
Posts: 4,648
Likes: 1,059
From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
DeWitts Radiator Installed
Over the weekend, I installed my new DeWitts 2 core radiator. It fit fine !
HOWEVER, you need to rent a spider monkey to put a couple of the little fasteners back into the radiator shroud. Those 3 small ones on either side that use a 7mm wrench (have a 7mm hex head) are a booger to put back in.
I ended up using a hemostat to hold the top one in place and got a finger on it, removed the hemostat and turned it enough to get it started. Then it was one flat at a time with an open end wrench as there isn't even enough room to get my 1/4" drive ratchet in there. I probably could have cut one of my sockets down, but ....
I also finished up putting on new pads, rotors and stainless steel flex lines.
Next is fixing the 1996 vent issue where there is a vacuum issue. Then the camber brace and then and then......
HOWEVER, you need to rent a spider monkey to put a couple of the little fasteners back into the radiator shroud. Those 3 small ones on either side that use a 7mm wrench (have a 7mm hex head) are a booger to put back in.
I ended up using a hemostat to hold the top one in place and got a finger on it, removed the hemostat and turned it enough to get it started. Then it was one flat at a time with an open end wrench as there isn't even enough room to get my 1/4" drive ratchet in there. I probably could have cut one of my sockets down, but ....
I also finished up putting on new pads, rotors and stainless steel flex lines.
Next is fixing the 1996 vent issue where there is a vacuum issue. Then the camber brace and then and then......
Thread Starter
Safety Car
Joined: Apr 2016
Posts: 4,648
Likes: 1,059
From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
A weekend mechanic can do it. Basically there is a lot of taking apart, then dropping in the radiator, then a lot of putting back together. Not real hard. Just have to remember what you took apart.
Do you have a FSM ? If not, you should get one, paper or electronic. An electronic one will work just fine as it is a direct copy.
Melting Slicks
Joined: Oct 2016
Posts: 2,024
Likes: 363
From: Central Alabama
HOWEVER, you need to rent a spider monkey to put a couple of the little fasteners back into the radiator shroud. Those 3 small ones on either side that use a 7mm wrench (have a 7mm hex head) are a booger to put back in.
I ended up using a hemostat to hold the top one in place and got a finger on it, removed the hemostat and turned it enough to get it started. Then it was one flat at a time with an open end wrench as there isn't even enough room to get my 1/4" drive ratchet in there. I probably could have cut one of my sockets down, but ...
I read somewhere on here that you should swap the nut plates to the bolt holes so you can put those back in from underneath
Thread Starter
Safety Car
Joined: Apr 2016
Posts: 4,648
Likes: 1,059
From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
As a good coolant system maintenance task, ensure that the inlet/outlet into the overflow tank is not plugged. Mine was. Once again, even though the car now has just over 15K miles, time causes issues (and maybe some GM radiator pills, which a TSB now says don't use).
A quick check is to blow air into the top line on the surge tank and if the overflow tank bubbles you are good. There was crud plugging mine up. I poked it out with a small screw driver and blew it out clean with air and got rid of the contaminated coolant.
Le Mans Master
Joined: May 2005
Posts: 7,329
Likes: 2,256
From: Central Maryland
Live well,
SJW
Advanced
Joined: Nov 2015
Posts: 79
Likes: 14
From: Santa Fe
Yes, the DeWitts radiator is a great thing!
I installed one in my '93 last year and with the 160 T-stat i run at 176 degrees
summer, winter - whenever.
And mine is the single row DeWitts - i'm too old to race any more i guess.
The trickiest part of the install was re-connecting the AT lines.
It's one of the last things to do (was for me anyhow) and came really, really close to
cross threading the tube fitting into the radiator, and googling a bunch of new cuss
words.
It just didn't feel right, so i backed it out, tweaked the line a bit and tried again.
Success, you have to thread that fitting a couple turns with just your fingers to start.
It's really tempting to just go gorilla at the start - DON'T.
I'm loving that DeWitts!
I installed one in my '93 last year and with the 160 T-stat i run at 176 degrees
summer, winter - whenever.
And mine is the single row DeWitts - i'm too old to race any more i guess.
The trickiest part of the install was re-connecting the AT lines.
It's one of the last things to do (was for me anyhow) and came really, really close to
cross threading the tube fitting into the radiator, and googling a bunch of new cuss
words.
It just didn't feel right, so i backed it out, tweaked the line a bit and tried again.
Success, you have to thread that fitting a couple turns with just your fingers to start.
It's really tempting to just go gorilla at the start - DON'T.
I'm loving that DeWitts!
Thread Starter
Safety Car
Joined: Apr 2016
Posts: 4,648
Likes: 1,059
From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
a trick I learned with fluid fittings is of course get them up at the end where they will turn freely on the tube and then slightly wiggle the tube as you are turning the fitting in.
a very slight wiggle is all you need. that slight movement frees the fitting to turn in, at least for me I have this works great. after 40 yrs of having to fix lots of beater cars in my day, it is just something I do
then if it takes more than a thumb and a forefinger on the wrench to start it going further.....stop
reading the above posts about reversing those nut plates triggered one of those "well duh" moments. most of us are so focused on putting it back together the way we took it apart that it just doesn't register, probably because you are tired by the time you get to those.
a very slight wiggle is all you need. that slight movement frees the fitting to turn in, at least for me I have this works great. after 40 yrs of having to fix lots of beater cars in my day, it is just something I do
then if it takes more than a thumb and a forefinger on the wrench to start it going further.....stop
reading the above posts about reversing those nut plates triggered one of those "well duh" moments. most of us are so focused on putting it back together the way we took it apart that it just doesn't register, probably because you are tired by the time you get to those.
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Melting Slicks
Joined: Oct 2016
Posts: 2,024
Likes: 363
From: Central Alabama
Yes, the DeWitts radiator is a great thing!
I installed one in my '93 last year and with the 160 T-stat i run at 176 degrees
summer, winter - whenever.
And mine is the single row DeWitts - i'm too old to race any more i guess.
The trickiest part of the install was re-connecting the AT lines.
It's one of the last things to do (was for me anyhow) and came really, really close to
cross threading the tube fitting into the radiator, and googling a bunch of new cuss
words.
It just didn't feel right, so i backed it out, tweaked the line a bit and tried again.
Success, you have to thread that fitting a couple turns with just your fingers to start.
It's really tempting to just go gorilla at the start - DON'T.
I'm loving that DeWitts!
I installed one in my '93 last year and with the 160 T-stat i run at 176 degrees
summer, winter - whenever.
And mine is the single row DeWitts - i'm too old to race any more i guess.
The trickiest part of the install was re-connecting the AT lines.
It's one of the last things to do (was for me anyhow) and came really, really close to
cross threading the tube fitting into the radiator, and googling a bunch of new cuss
words.
It just didn't feel right, so i backed it out, tweaked the line a bit and tried again.
Success, you have to thread that fitting a couple turns with just your fingers to start.
It's really tempting to just go gorilla at the start - DON'T.
I'm loving that DeWitts!
Don't have a ton of faith in the what appears to be 25 year old factory unit.
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
Nice up-grade.. and piece of mind ditching the plastic end caps. Reversing the 3 nut plates does make reassembly much easier! Also; this is a good time to clean the Condenser coil, they get loaded up with small piece's of road debris.. pebbles etc.. and last but not least, this is also a good time to replace the Original 3/8" cooling hose's if they haven't already been done. When I did mine I discovered at the Radiator to Surge tank Aluminum Tube GM installed a Brass "Restrict-or" insert that was mostly plugged. I have a 95 I don't Know if the earlier Vettes have the same Brass Restrict-or.. 
Melting Slicks
Joined: Oct 2016
Posts: 2,024
Likes: 363
From: Central Alabama
Pro
Joined: Nov 2007
Posts: 617
Likes: 8
From: Morgan City LA
Do you mean coolant, not freon ? You don't touch the a/c condenser or lines. You have to drain the coolant from the radiator, but not the whole block, at least on the LT1's as the radiator hoses sit pretty high.
A weekend mechanic can do it. Basically there is a lot of taking apart, then dropping in the radiator, then a lot of putting back together. Not real hard. Just have to remember what you took apart.
Do you have a FSM ? If not, you should get one, paper or electronic. An electronic one will work just fine as it is a direct copy.
A weekend mechanic can do it. Basically there is a lot of taking apart, then dropping in the radiator, then a lot of putting back together. Not real hard. Just have to remember what you took apart.
Do you have a FSM ? If not, you should get one, paper or electronic. An electronic one will work just fine as it is a direct copy.
Yeah i meant freon , atleast that's what i was told i had to do. Mine is a 96 CE with MT. Where can i get the electronic FSM. thanks for replying!
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,008
From: Texas
If you don't discharge the AC. the biggest PIA of the whole process is removing the shroud. Takes a little work to get it around the condenser lines. Worth 15 minutes of solving the puzzle and applying a little force vs needing to vacuum and the re-charge the AC system.