Do all C4's run on the hot side?
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From: Pikeville TN
Do all C4's run on the hot side?
I just purchased a 1995 coupe last month and I'm curious if this is a common problem. While driving at speed of 30 or above the coolant temperatures stays between 200 and 210. Under 30 and stopped, it quicklyclimbs to 230 to 235. After driving off it qoes back to 210 pretty quickly. Is this normal?
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Re: Do all C4's run on the hot side? (pkvvette)
Welcome aboard. :cheers: They do run a little warm but you might want to check out the radiator plenum area for trash. Look in the Tech Paper section of the forum for a 'how to' paper on this. Most C4s need to have this area cleaned. :seeya
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From: Cincinnati Oh
Re: Do all C4's run on the hot side? (pkvvette)
Unfortunately, yes. Good news there is a solution. GM let the LT1/4 run hotter for emission purposes, but that doesn't help longevity or performance. First pull your radiator and clean it with a hose. It is the only way to get out all the crap scooped up over the years. Second, you can program your fan settings to come on earlier (stock is 235). Third, you can change to a 160* thremostat to help you run cooler on the hwy.
Enjoy the car! :chevy
Enjoy the car! :chevy
Burning Brakes
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From: Arlington TN
Re: Do all C4's run on the hot side? (pkvvette)
Yes they run on the warm side by design.
Yours does seem a little warm for my taste and what I get from mine.
If I'm running down the road above 30MPH I'm at 194 to 196 when it is in the 90s outside. IF I set at a light it runs up to 225 and then the fans kick on. I've seen 228 but that is about the Hottest mine has got. Mine is stock. The settings from GM on the fans is 225 to kick on and cool it down to 217 then turn off the back up fan (second fan) comes on around 240. I would say your ok but you might check to make sure that the everything is clean in front and make sure that the flow is good in your cooling system.
You can get a switch bypass to run the fans sooner or Hypertech makes a programmer and you can change the fans settings if you want it to run cooler.
PS: WELCOME!! :seeya
[Modified by Corvette1996LT1, 1:18 PM 6/19/2003]
Yours does seem a little warm for my taste and what I get from mine.
If I'm running down the road above 30MPH I'm at 194 to 196 when it is in the 90s outside. IF I set at a light it runs up to 225 and then the fans kick on. I've seen 228 but that is about the Hottest mine has got. Mine is stock. The settings from GM on the fans is 225 to kick on and cool it down to 217 then turn off the back up fan (second fan) comes on around 240. I would say your ok but you might check to make sure that the everything is clean in front and make sure that the flow is good in your cooling system.
You can get a switch bypass to run the fans sooner or Hypertech makes a programmer and you can change the fans settings if you want it to run cooler.
PS: WELCOME!! :seeya
[Modified by Corvette1996LT1, 1:18 PM 6/19/2003]
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Re: Do all C4's run on the hot side? (joecaver)
Welcome aboard. :cheers: They do run a little warm but you might want to check out the radiator plenum area for trash. Look in the Tech Paper section of the forum for a 'how to' paper on this. Most C4s need to have this area cleaned. :seeya
BTW - Welcome
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From: Traverse City MI
Re: Do all C4's run on the hot side? (pkvvette)
A cooling system fluch and a cleaned out radiator will go a long ways to helping your C4 stay cool. The LT1s like to run about 190ish to 200ish stock. In stop and go traffic the temp will climb to 230 then the fans will kick on. You car also turn your fans on my turning the AC on. A 160 thermastat won't do much unless you program the fans to come on sooner.
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Re: Do all C4's run on the hot side? (69mako)
You wire in one of these fan switches advertised in MAD or Ecklers, etc. to the main fan.
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Re: Do all C4's run on the hot side? (pkvvette)
MY LT1 ran like that and I took the followiung steps to rectify it...
1. Removed the radiator form the car to clean all the road trash that gathers in the front of it (you cant get to it good enough unless you have the radiator out).
2. Took the radiator in to have it dipped/clean and ram rodded (i forget the name for the procedure.. they basically take the side tanks off of the radiator and run a thin piece of metal in all the cores to clean the built up gunk out)
3. after install filled with water and flushed the system and refilled with a 50%/50% mix..
4. installed new waterpump (and opti while i was in there)
after all that the car ran MUCHMUCH cooler.. never about 220 even when I was living out in the desert (PHOENIX) where the temps get in the 120's
For the 383 because of the increased cubes and higher compression im going to run a 160 degree themostat and am having the guys at PCMforless.com burn me a new chip for the new cam, cubes and to turn the fans on earlier..
hope that helps
1. Removed the radiator form the car to clean all the road trash that gathers in the front of it (you cant get to it good enough unless you have the radiator out).
2. Took the radiator in to have it dipped/clean and ram rodded (i forget the name for the procedure.. they basically take the side tanks off of the radiator and run a thin piece of metal in all the cores to clean the built up gunk out)
3. after install filled with water and flushed the system and refilled with a 50%/50% mix..
4. installed new waterpump (and opti while i was in there)
after all that the car ran MUCHMUCH cooler.. never about 220 even when I was living out in the desert (PHOENIX) where the temps get in the 120's
For the 383 because of the increased cubes and higher compression im going to run a 160 degree themostat and am having the guys at PCMforless.com burn me a new chip for the new cam, cubes and to turn the fans on earlier..
hope that helps
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From: Pikeville TN
Re: Do all C4's run on the hot side? (pkvvette)
Thanks for all the info folks. I'm back with an update. Since my vette was already in the shop for a new starter, I had them pull the radiator using the instructions on the tech sheet posted on this site. The shop also informed me that my computer was sending out a -13 oil tem reading even though my gauges were reading 200 in the car. He replaced the oil temp sensor and did the cleanout around the radiator. My car now runs at 194 to 198 on the road and 210 to 218 stopped at a light. I'm really tickled with the results and thanks again for the help!
Melting Slicks
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From: Lebanon KY
Re: Do all C4's run on the hot side? (Cal Vette)
With the 160 degree thermostat, and hyper tech chip ( that kicks the fans on early) mine runs below 200. Even in hot weather. :thumbs:
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From: OBAMA IS HITLER
Re: Do all C4's run on the hot side? (pkvvette)
Thanks for all the info folks. I'm back with an update. Since my vette was already in the shop for a new starter, I had them pull the radiator using the instructions on the tech sheet posted on this site. The shop also informed me that my computer was sending out a -13 oil tem reading even though my gauges were reading 200 in the car. He replaced the oil temp sensor and did the cleanout around the radiator. My car now runs at 194 to 198 on the road and 210 to 218 stopped at a light. I'm really tickled with the results and thanks again for the help!
Burning Brakes
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From: Costa Mesa CA
Re: Do all C4's run on the hot side? (pkvvette)
Yeah, I replaced the radiator, installed the lower temp switch so the fans come on at 200F instead of 225F and left the thermo out entirely. You can do that in AZ same as CA. The fans seldom come on with factory timing and the TPS set correctly. On the freeway this time of year I'll seldom see over 155F. Around town, maybe 190F but most likely in the 180's.
Glad you got it fixed.
BIG JIM
Glad you got it fixed.
BIG JIM
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From: tucson AZ
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Re: Do all C4's run on the hot side? (pkvvette)
They don't have to, if you do your homework.....say good bye to cracked plastic connections and cool it down...like many ways, as you've already seen.....on this forum......
Good Luck
tony
:cool:
Good Luck
tony
:cool:
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From: Lawrenceville GA
Re: Do all C4's run on the hot side? (R94 LT 1)
I have a '95 also, temp is about the same as you described... Not worried about it too much though, I'll do something about it eventually.
That looks like the remains of a bird or something in that radiator. That was cool, what's up with that? :lol:
That looks like the remains of a bird or something in that radiator. That was cool, what's up with that? :lol:
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From: Pikeville TN
Re: Do all C4's run on the hot side? (AllDreamsAreRed)
This lower temp fan switch, is this the manual override version or can you get a lower temp fan switch that is still computer controlled? The only ones I have seen are completely manual and lock the computer out. Where can you get a lower temp fan switch that is still computer controlled?
Melting Slicks
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From: Winchester Ontario
Re: Do all C4's run on the hot side? (pkvvette)
Not trying to hijack tEh thread, but...
My 89 383 runs hot too. On the highway, it runs right at 180. Perfect!! It has a 180 T-stat. But, in town in hot weather at low speeds and idle it can get over 230-240. That, I've heard is somewhat normal, but still a little high for me. I have a custom chip that turns the fan on earlier, and I also hotwired the fans to a toggle switch and have them on all the time in this hot weather. If I ran a 160, would the coolant stay around 160 on the highway?
The previous owner had installed a screen under the front bumper to stop any crap from getting sucked up to the rad.
I think I'm gonna get the rad flushed, cuz I've heard that it can get clogged up. My mechanic seems to remember pulling the rad whenever we changed engines, and didn't remember seeing any crap stuck to the rad. How much will running straight water and maybe a bottle of water wetter help me? (If I can find the damned stuff locally, no body has heard of it where I live!)
[Modified by black_89_vette, 3:12 PM 6/25/2003]
My 89 383 runs hot too. On the highway, it runs right at 180. Perfect!! It has a 180 T-stat. But, in town in hot weather at low speeds and idle it can get over 230-240. That, I've heard is somewhat normal, but still a little high for me. I have a custom chip that turns the fan on earlier, and I also hotwired the fans to a toggle switch and have them on all the time in this hot weather. If I ran a 160, would the coolant stay around 160 on the highway?
The previous owner had installed a screen under the front bumper to stop any crap from getting sucked up to the rad.
I think I'm gonna get the rad flushed, cuz I've heard that it can get clogged up. My mechanic seems to remember pulling the rad whenever we changed engines, and didn't remember seeing any crap stuck to the rad. How much will running straight water and maybe a bottle of water wetter help me? (If I can find the damned stuff locally, no body has heard of it where I live!)
[Modified by black_89_vette, 3:12 PM 6/25/2003]
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From: Cincinnati Oh
Re: Do all C4's run on the hot side? (black_89_vette)
But, in town in hot weather at low speeds and idle it can get over 230-240. I have a custom chip that turns the fan on earlier, and I also hotwired the fans to a toggle switch and have them on all the time in this hot weather. If I ran a 160, would the coolant stay around 160 on the highway?
If you ran a 160* you'd most likely see 170-175 or so on the hwy for coolant temps.