bwagner

How hot do C4's run? Mine is a 94 with 117,000 on it. New wires, plugs, water pump, opti spark blah blah blah......yesterday at a stop with the air on it got up to 236. Is that a little to hot, it was about mid 80's out......

JB666

I'm beginning to wonder if this is 'normal'!! After a full flush/refill yesterday, and 3 rides, I'm idling around 225 and hitting 240. Worst part, it was 39 degrees last night! I'm thinking the Tstat is a good place to start, and may be for you... 180 is a happy in between it appears, from all the archived posts I've been reading.

Mr Mojo

220 for oil and 195-210 for coolant at highway speeds. 230 at idle is pretty common.

Although with the A/C on, you shouldn't see it that high. Also when's the last time you cleaned all the crap out from in front of your radiator?

bwagner

Clean the crap out from the front of the radiator :confused: *scratches his head*...meaning like trash kicked up from driving?
One thing that I did do the other day was on the hose running from the water pump going to the heater core. There's a plastic valve that cracked that I replaced with just a plastic insert tube. Now on the piece that broke it showed an arrow and stated heater core on it. Letting you know what way to point it. What I replaced it with, like I said was just a plastic tube. They didn't have anything like what came off it. What purpose did that thing have if any?

[Modified by bwagner, 8:12 AM 4/25/2003]


[Modified by bwagner, 8:13 AM 4/25/2003]

Steel Blue 91

:iagree:
These cars were designed to run at those temps for emissions and average corporate fuel economy. Your fan should be coming on at ~230 to 235 (this maybe incorrect due to long hours and a bad memory). There are several ways to keep the temps in line: manual fan switch, reprogrammed chip (turns the fans on earlier). Run a search and you'll find more info. I run a 160 degree stat, Ed Wright chip and cleaned the radiator in the fall. I have yet to see the temp exceed 195 degrees. Normally runs about 180 to 190 even in traffic.

vader86

These temps are normal, our engines are designed to run hotter to pass emissions.

Remove the radiator shroud, and youll see in between the radiator and condensor that there will be alot of trash and road debris. This causes your temps to be higher by about 15-20F. Then flush the system and replace the thermostat with a 180 or 160 (stock is 180 in LT1s).

Then wire in a fan switch to make the fans come on earlier, and the problem will likely go away.

Richard G

When I bought my 94LT1 last year I saw your high temperature. I cleaned the outside of the radiater ands flushed the coolant system. Now the highest I see is 223. Both fans should kick on with the AC on and you should see temps going down in about 4 or 5 seconds, at least that is what I see on my Corvette.

JB666

Thanks for all the replies, guy!! Well, I took it to work today (45 degrees this morning), and it ran at about 193-195 on the highway, and 200 on the back roads for my whopping 6 mile drive in.. It just made me nervous last night to see upwards to 250 show up!! BUT, I learned that I bled my system wrong, after I flushed/filled it... So, today at lunch I'll bleed it with the car ON and see if that let's more air out? I bled it 4 times last night, but all 4, it was off...

As for getting the computer reprogrammed to turn on the fans earlier, is this a difficult & expensive process??

Jeff

my ride

Last summer I saw the same temps your experiencing. Last fall I removed the radiator and cleaned all the crap out (leaves, paper, sand and grass), performed the throttle body bypass, flushed the system including removing the knock sensors, I added a bottle of Redline WaterWetter, I replaced all of the hose clamps and any bad hoses, I installed a screen in front above the front spoiler to keep large crap off the radiator, I also installed an Ed Wright FastChip. In Washington, DC traffic (stop and go- bumper to bumper) with 80 Deg temps the max temp I've seen so far this year is 182 Deg. The inside of the Vette stays cooler too and I'm getting better mileage with Ed Wright's chip about 1.5 MPG more. My Vette is a 92 LT1. Hope this helps!

One thing I forgot to add was I installed a 160 Deg Thermostat and the Ed Wright chip was the one that requires a 160 Deg Thermostat. I feel the work was well worth it and I got the results that I wanted! :cool:


[Modified by my ride, 11:36 AM 4/25/2003]

vader86

Clean the front of that radiator first, maybe add a bottle of Water Wetter and try the switch.

Custom programs are expensive, and the Hypertech unit costs more than its worth.

ZELLSLIFE

I had my thermostat fail not to long ago it failed closed it was well marked by a 100 degree split between digital and analog guages at start up the next day after it overheated by night before. :seeya

John Row

That little plastic thing is a restrictor to keep from running too much coolant throught the heater core. You need to have it otherwise too much coolant is bypassing the radiator.

You can't just buy the restrictor, you have to buy the entire hose (2 pieces). Good news is that it's around $30 bucks, the bad news it's probably not in stock.

bwagner

Why would you have to get the entire hose, it comes right off. The hoses are just hoses???? :confused: They just don't sale the restrictor? So would this be causing it to run hotter or not having it bleed good enough?

John Row

Why don't they stock the restrictor, it's probably a bean counter thing.

This could cause it to run hotter, more coolant is going to the heater core and less coolant is going through the radiator. The heater core isn't as efficient at radiating heat as the radiator, i.e. larger tubes, less surface area, less air flow.

Alex D

I put a new radiator in, flushed the system and put a 160F thermostat in and my car runs consistently at 173 to 180 F coolant temp, no more. most often the trash build-up in front of the radiator is the problem and that can only be cleaned thoroughly by removing the shroud......it is well worth it......

wz2wj1

I have a 94 , bought it last year. I use to see temp in the 225 to 235 range and higher on hot days. I installed a manual fan switch that turns both fans on, relitively simple and inexpensive; pita. I have now installed a 180 thermostat and changed the fan on/off with a Hypertech programmer, have a bottle of water wetter installed and 217degrees is the highest i've seen. Usually runs 205 to 210.

Blue 92

160 stat with reset fans. Rarely see over 180.

The13Bats

a few weeks ago I just got a c4 86 with 90 something miles I posted about this same topic....It was hitting 245+ in traffic or stopped with air on or off....I noticed the two front intake bolts on the drivers side were leaking the front one water the second oil I put sealer on both and fixed that....I then put a 180 sat in, the one I removed was 160 and it did open when boiled on the stove....
Now in 90+ degree Fl days stuck in traffic air on or off it gets 215 220 tops...
but mostly stays around 195-20-something....I haven't looked into the trash that gets stuck on the front of the radiator, I was told in my post that you can wash it out with a garden hose from the back side,
The one pesty problem mine still has is sometimes the "low coolant" lamp comes on for a few then goes off but if I look in the radiator it's full
:skep: I have also noticed the front factory air damn is missing do I really need it?
I guess these cars do run a bit hotter than the cars of yesterday....
the two questions I still have are, would I have been better off with a new 160 stat or is the 180 good and does this "low coolant" sender sometimes lie?
:thumbs:


[Modified by The13Bats, 7:22 PM 4/25/2003]

vader86

You can get SOME of it out by the pressure, but you wont get it clean.

yes, the air dam is integral to your cooling setup. Our cars do run hotter for emissions purposes.

Whether you pick 160 or 180 depends on the climate where you are, and how much you drive in winter. I have a 160 in my 86 here in SC. If i drove daily during winter id switch to a 180 for winter.

You live in FL, so you should run a 160 year-round.


[Modified by vader86, 10:21 PM 4/25/2003]

The13Bats

Okay Vader, how do we get our radiators clean?

In my case would removing the 180 sat and putting a new 160 sat in make my car run even cooler, keep in mind I'm in central FL in the 80-90's most of the year...

The Air damn works only when moving to create a low pressure area, no big deal to replace that, the reason I asked "do I really need it " is I don't really consider my car running too hot any longer...and it's not there but I don't argue they are they for a reason....

Thanks, C. :thumbs: