c4 radiator
Melting Slicks
Joined: Feb 2015
Posts: 2,069
Likes: 262
From: Park Ridge New Jersey
DeWitts, but I'd pick some brains here and do some searches. Since it is fairly new to you, you might want to check the area between the condenser and the radiator, lots of crap accumulates there. If its dirty, clean it up and I bet it runs cooler
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
What coolant temps do you see? There is a good sticky thread that covers coolant temps for the C4. C4's (both the L98 and the LT1 engines) tend to run warmer than other cars. That's due to helping with lowering emissions.
You should check around the tubes and fins of the radiator and A/C condensor for dirt and debris that could be reducing air flow. Lack of airflow, higher temps
. Also make sure the air dams under the front of the car are in place. C4's are "bottom breathers"; cooling air is directed upwards into the condensor and radiator by these air dams.
You should check around the tubes and fins of the radiator and A/C condensor for dirt and debris that could be reducing air flow. Lack of airflow, higher temps
. Also make sure the air dams under the front of the car are in place. C4's are "bottom breathers"; cooling air is directed upwards into the condensor and radiator by these air dams.
1st Gear
Joined: Dec 2017
Posts: 1
Likes: 0
What coolant temps do you see? There is a good sticky thread that covers coolant temps for the C4. C4's (both the L98 and the LT1 engines) tend to run warmer than other cars. That's due to helping with lowering emissions.
You should check around the tubes and fins of the radiator and A/C condensor for dirt and debris that could be reducing air flow. Lack of airflow, higher temps. Also make sure the air dams under the front of the car are in place. C4's are "bottom breathers"; cooling air is directed upwards into the condensor and radiator by these air dams.
You should check around the tubes and fins of the radiator and A/C condensor for dirt and debris that could be reducing air flow. Lack of airflow, higher temps
. Also make sure the air dams under the front of the car are in place. C4's are "bottom breathers"; cooling air is directed upwards into the condensor and radiator by these air dams.it all looks clea temp runs up on guage 240 after a short time in town I was going to drain coolant system and replace antifreeze however if it was best to replace radiator iwas going to wait anjd do it all at once
Melting Slicks
Joined: Feb 2015
Posts: 2,069
Likes: 262
From: Park Ridge New Jersey
if you replace the coolant make sure you get the air out of the system
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
On the LT1 C4's - the PCM is programmed to let the car get to 230 or so (looking at the digital gauge - not he analog coolant temp gauge - which can tend to be inaccurate) before the 2nd fan cuts in. Most of the LT1 cars will run in the mid 190's on the open highway in steady state cruise at 65 or so MPH in moderate to warm weather. If you're seeing more than that - you should look to find out what the problem is.
As other posters have said - the area between the A/C condenser and the rad tends to accumulate crap. Cleaning it out ain't fun - - basically you get to pull the rad - and there are six little 7mm screws in front of the air box that just aren't your friend that need to come out to get the rad out.... But doing the work is likely to help the cooling.
Doing a FULL coolant drain and flush will also help - on the LT1 Cars that means draining the rad - then pulling the knock sensors which are threaded into the holes that used to be called the block drains. Many LT1 owners are amazed by the amount of crud that comes out when those drain plugs are removed - part of it has to do with the reverse flow cooling system the LT1 cars used. Not a bad idea to change rad hoses while you're at it.
As other posters have said - the area between the A/C condenser and the rad tends to accumulate crap. Cleaning it out ain't fun - - basically you get to pull the rad - and there are six little 7mm screws in front of the air box that just aren't your friend that need to come out to get the rad out.... But doing the work is likely to help the cooling.
Doing a FULL coolant drain and flush will also help - on the LT1 Cars that means draining the rad - then pulling the knock sensors which are threaded into the holes that used to be called the block drains. Many LT1 owners are amazed by the amount of crud that comes out when those drain plugs are removed - part of it has to do with the reverse flow cooling system the LT1 cars used. Not a bad idea to change rad hoses while you're at it.
Thread Starter
3rd Gear
Joined: Mar 2018
Posts: 3
Likes: 0
Thanks a lot I appreciate all your replies I used to think I knew something about wrenching until I got this vette it’s different reading your replies I’m seeing how much
I know this weekend I will be busy pulling the rad and flushing the system
I know this weekend I will be busy pulling the rad and flushing the system
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Safety Car
Joined: Aug 2009
Posts: 3,751
Likes: 276
From: Melbourne, Victoria, Australia
Most 3 row radiators only have 3x 1/2 inch rows....
You can find good two row 2x 1 inch rows radiators, stay away from Chinese ones ..... most cheap ones are...
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Burning Brakes
Joined: Apr 2009
Posts: 1,185
Likes: 33
From: Charlotte Michigan
I replaced mine with the direct fit single core from DeWitts and installed the Spal fans. Works great!
Only about 50 miles from them, so went over there. Talked to John and they made bracket holes to mount ac condensor and a extension bushing for the upper hose bracket to be used.
Only about 50 miles from them, so went over there. Talked to John and they made bracket holes to mount ac condensor and a extension bushing for the upper hose bracket to be used.
Melting Slicks
Joined: May 2013
Posts: 2,692
Likes: 349
From: Sacramento California
The analog temperature gauge should be ignored.
The scale is not linear and shows alarming readings when all is OK.
Cycle the digital display to show the coolant temperature, that is most accurate. See what it says and report back here.
Instructor
Joined: Aug 2016
Posts: 240
Likes: 51
From: Putnam County NY
I replaced the radiator in my coupe with the DeWitts dual core almost 2 years ago. The temperature is more stable now, averages around 200 in the city, 209 max. I wanted a full aluminum unit and not the plastic/aluminum type that came from the factory.
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
Surprised nobody has mentioned this yet:
The analog temperature gauge should be ignored.
The scale is not linear and shows alarming readings when all is OK.
Cycle the digital display to show the coolant temperature, that is most accurate. See what it says and report back here.
The analog temperature gauge should be ignored.
The scale is not linear and shows alarming readings when all is OK.
Cycle the digital display to show the coolant temperature, that is most accurate. See what it says and report back here.
I think I did ... "(looking at the digital gauge - not he analog coolant temp gauge - which can tend to be inaccurate)"....
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,074
From: Lansing MI
In the event the radiator is replaced, then I totally agree the replacement should not have plastic side tanks.
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
BTW - westex A new aluminum rad - ( e.g. a Ron Davis, DeWitts or Be Cool) is going to run AT LEAST $500 - probably more - maybe way more.... And it typically involves some minor mods to the rad shrouding...
So - spending a few hours and $40 on coolant and distilled water is probably a worthwhile course of action. Worst case - your out the $40 when you find you have to replace the rad anyway (and in that case - you may only need to get one more jug of Anti-freeze - because you won't lose as much when you just remove the rad.....)
Oh - and one other piece of advice - plan on getting old coolant all over (both the floor and you) when you pull the knock sensors. I've done the knock sensor removal job more than once, and let's just say that: 1) wearing goggle sis a good idea - and 2) I wear stuff that I fully expect to hose off before throwing in the washer - and 3) I generally plan to get into the shower right after the job is done... So the knock sensor removal is not a job to do with hot coolant...
So - spending a few hours and $40 on coolant and distilled water is probably a worthwhile course of action. Worst case - your out the $40 when you find you have to replace the rad anyway (and in that case - you may only need to get one more jug of Anti-freeze - because you won't lose as much when you just remove the rad.....)
Oh - and one other piece of advice - plan on getting old coolant all over (both the floor and you) when you pull the knock sensors. I've done the knock sensor removal job more than once, and let's just say that: 1) wearing goggle sis a good idea - and 2) I wear stuff that I fully expect to hose off before throwing in the washer - and 3) I generally plan to get into the shower right after the job is done... So the knock sensor removal is not a job to do with hot coolant...
Instructor
Joined: Mar 2008
Posts: 226
Likes: 6
From: NY
Purchased a 2 row DeWitts earlier this year for my '96 LT4, during their annual sale. Haven't installed it yet, but pulled it out of the box to inspect...have to say, the thing looks likes it's really high quality, to be honest, it looks like a piece of art!
Race Director
Joined: Feb 2003
Posts: 11,671
Likes: 20
From: Lake Wylie SC
Do you mind saying how much it cost? The bottom hose nipple on my radiator has a crack in it.
Instructor
Joined: Mar 2008
Posts: 226
Likes: 6
From: NY
Honestly, I can't recall right now...I'd have to look it up. Probably right around $500, with shipping. Remember though, it was during their annual sale, that I believe only occurs in January.