Cooling system
Thread Starter
Intermediate
Joined: Feb 2003
Posts: 44
Likes: 0
From: Mesa AZ
Cooling system
I own a 1994 C4 Coupe with 68,000 miles. I live in Az and am about to add 40 below to the system as I am having cooling issues in town with all the short stops and need to know what the coolent fluid cpacity in gallons.
Can ayone help out here.
Thanks in advance,
Can ayone help out here.
Thanks in advance,
Pro
Joined: Dec 2002
Posts: 603
Likes: 0
From: 84 383 XFire Chandler, AZ
AZMike - Before you add the stuff make sure area between the AC condenser and radiator are free of debris. This is a common problem and you will be amazed the amount for crap that accumulates there. I understand what you are dealing with in AZ - I live in Chandler.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Adding stuff to the coolant is not the best fix unless you have checked out the cooling system for any potential problems. Junk in the front of the radiator is the biggest problem Corvettes have with effective cooling. You can direct a stream of water from the fan side through the radiator fins to loosen any debris from the front of the radiator. Make sure the A/C condensor coil is clear too.
The system is designed to run hot for helping with emissions so seeing temps anywhere from 197 to the low 230's is normal. The secondary fan is supposed to come on at 228 so make sure it runs. Turning on the A/C forces the secondary fan on.
Check the radiator hoses for softness. If the lower hose is soft it could be collapsing and cutting of the flow of coolant. Do a complete coolant system flush every other year using a good ethlylene glycol (green)antifreeze and distilled water in a 50-50 mix.
The system is designed to run hot for helping with emissions so seeing temps anywhere from 197 to the low 230's is normal. The secondary fan is supposed to come on at 228 so make sure it runs. Turning on the A/C forces the secondary fan on.
Check the radiator hoses for softness. If the lower hose is soft it could be collapsing and cutting of the flow of coolant. Do a complete coolant system flush every other year using a good ethlylene glycol (green)antifreeze and distilled water in a 50-50 mix.
Intermediate
Joined: Apr 2004
Posts: 31
Likes: 0
From: Willington CT
Good time to change the thermostat / gasket. Check the cooling hoses, especially to the throttle body & lower radiator hose. Add a Prestone flush kit and flush the system. Pull the knock sensor to drain the block. Add the new coolant.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
In AZ I would not hesitate to run a 160 thermostat.
You should check the space between Condensor and Radiator, and the only way to do so is removing the shroud, dont be lazy and try to get it from underneath.
Flush and refill the system, see if its any better.
You should check the space between Condensor and Radiator, and the only way to do so is removing the shroud, dont be lazy and try to get it from underneath.
Flush and refill the system, see if its any better.
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
running warm
I live in south Florida and it gets hot down here also. An easy tip is
to check the 3" space between the radiator and the A/C condensor.
The easy way to check this is with a flash light and look at a 2 1/2"
space on the passengers side. You can get a clear view of what is in
there and isnt. A long tube(3' PCV pipe) attached to a vacuum cleaner
will clean the entire radiator. I've made some adjustments on the 3'
extention pcv pipe like cut a 45 degree angle at the end. Try it.
to check the 3" space between the radiator and the A/C condensor.
The easy way to check this is with a flash light and look at a 2 1/2"
space on the passengers side. You can get a clear view of what is in
there and isnt. A long tube(3' PCV pipe) attached to a vacuum cleaner
will clean the entire radiator. I've made some adjustments on the 3'
extention pcv pipe like cut a 45 degree angle at the end. Try it.
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Thread Starter
Intermediate
Joined: Feb 2003
Posts: 44
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From: Mesa AZ
First thanks for all of your replies, its not every time that I get people to reply.Now I have a new belts water pump, the radiator front and in front of the condensor is clean. I have seem some real garbage in there from time to time and I always try to avoid road trash when I can. I just changed the thermostat to a 160 and have been running on it for two days now.
It helps from the standpoint that it takes it longer to heat up and when I run with out the ac I can now stay at 227 degrees if I'm not idling for extended periods of time in traffic.
I do however still have the same issue when I run the AC and in Arizona you need the AC this time of year.
Has anyone used the cooling additive 40 below? It is sold by ecklers and mid america. Are there any issues to look out for if I were to use it.
use distilled water and your anti freeze/boil
Thread Starter
Intermediate
Joined: Feb 2003
Posts: 44
Likes: 0
From: Mesa AZ
Originally Posted by nobodyunknown
40 below is for sale at autozone,$20.
Is your front air dam connected properly?
Try a fan switch that comes on at 200 degrees.
Is your front air dam connected properly?
Try a fan switch that comes on at 200 degrees.
Melting Slicks
Joined: Oct 2000
Posts: 2,491
Likes: 1
From: prescott AZ
I used 40 Below years ago in my 85. It was in the system for about 7 months when I started to hear a hissing sounds from the radiator cap. When I opened the cap there was a thick sludge that was preventing the cap from sealing. It took many flushes to get the system clean again. The system was spotless before the 40 Below. Besides that I never saw any type of temperature reduction at all.
Melting Slicks
Joined: Nov 2000
Posts: 2,469
Likes: 6
From: Winchester Ontario
I have used straight distilled water and a can of 40 Below. My coolant temperatures dropped by a fair bit, but this was also the same time that a fan motor was going out of me.
I have yet to try the Redline Water Wetter, although I have a bottle of it. Right now, I have no cooling issues, so I guess I'm too lazy putting the Water Wetter in.
I have yet to try the Redline Water Wetter, although I have a bottle of it. Right now, I have no cooling issues, so I guess I'm too lazy putting the Water Wetter in.
Thread Starter
Intermediate
Joined: Feb 2003
Posts: 44
Likes: 0
From: Mesa AZ
Thanks -
Hello all,
Sorry it took me so long to reply. Here is the fix that worked for me. I needed a new radiator. The one I had was not flushed frequently by the previously owner. I bought an after market replacment for $160 and now never see a temperature in the summer months above 228F when sitting in traffic.
Thanks for all the inputs.
Sorry it took me so long to reply. Here is the fix that worked for me. I needed a new radiator. The one I had was not flushed frequently by the previously owner. I bought an after market replacment for $160 and now never see a temperature in the summer months above 228F when sitting in traffic.
Thanks for all the inputs.
