72MiuraSV

Hi, My Corvette is getting quite hot when I am stoped at a red light or in traffic. My Corvette runs at 195-205 when moving but steadily gets up to 230 when I am stopped. After the tempature reaches 230 it starts to cool down. It gets down to about 220 and then goes right back up. I'm thinking this is way too hot. I'm not sure what tempature a stock Lt1 fan should kick in but I think 230 is way too hot, does anybody else have this problem?

kenmohr

That's correct operation. The fans turn on at 230*. When you start down the road it should go back to 195*-205*, Check for debree in front of radiator but other than that all is well.

WW7

What your seeing are normal temps..On these cars it's mandatory to check in front of the radiator every few years for accumulated trash....WW

DA1984VETTE

c4cruiser

The ability to get air flowing thru the radiator is important to effective cooling. The air conditioning condenser sits in front of the radiator so that needs to be clear of dirt and debris too. You can use a garden hose to help clear junk out. Aim a stream of water from the engine side of the radiator to flush the big chunks out. You can also use a vacuum to remove leaves and stuff from the gap between the A/C condenser and radiator.

IMHO, consistent 230 degrees idling is not really a good thing especially if the temp drops when the fans come on and then goes right back up. A LT1 cooling system in good condition should not let temps get much over 220 or so even in hot weather. My 92 never did see temps over 230 unless the outside air temp was above 85 to 90 degrees. It pretty much ran at 190 to 205 unless I was doing track days or the ambient air temp was high.

Are the fans coming on? Get the engine to operating temp and when you see the high temps look at the fans to make sure they are working. When was the last time you did a cooling system service? Drain and refill the system with fresh coolant. If the upper and lower radiator hoses are original to the car, they should get replaced.

Other possibilities are a thermostat sticking, water pump impeller corroded, and general gunk and corrosion in the block. An original radiator could be worn out if the car has high mileage.

PLRX

here it comes the summer.

http://forums.corvetteforum.com/c4-g...erheating.html

http://forums.corvetteforum.com/c4-g...erheating.html

http://forums.corvetteforum.com/c4-g...ing-issue.html

WW7

If you don't like the high temps your car is now running you can always get a kit from one of the Corvette sites that turns your fans on at a lower temperture..You would also have to install a lower temp thermostat to allow the coolant to get to a lower temp. I would suggest a 180 degree stat if you go this route..Do a search, there is plenty on this subject in the archives.....WW

72MiuraSV

Thank you everyone for the info, I just wanted to make sure that it was safe to drive my Corvette with the tempature getting up that high. That's crazy GM designed the LT1 to run that hot "normally"!

rithsleeper

230 completely normal. However, i dont like the temps either. Find the fan relay, find the ground wire the the comp grounds to open the relay and run a switch to the cab. Then turn your fan on when temps hit 210... thats what i do. I like switches though.

desertmike1

normal.....

C422

While I have an L98, I don't think this is "normal" operation.

That's how my car acted when I first got it. Over time, it got worse, even with routine cleaning of the radiator. I found that turning my AC off made it much worse, and that turning the heat on made it no better. Heater core had gone out, but not enough to dump into the cabin.

I noticed the temperatures still weren't in the closed-loop 190-205 that my manual said they should be. Replaced the radiator, and haven't been over 210 since. I'm in Georgia, and even on 100 degree+ days in stop-and-go traffic on I85 after driving an hour at 70 on 316 there's not been a single time that my temps got over 210.

Thermally, the hotter the temps are, the more wear your engine has to take. Of course, you also have a higher Carnot efficiency, thus potentially better power. But probably not.

Tom400CFI

Your "thinking" is incorrect. For normal operating temps, wear and power.

93Rubie

Modern engines run in the 190-210 range for the most part, make more power, burn cleaner, use less fuel, than they ever did. A cooler running engine might make a bit more power but at what cost to wear,fuel mileage,etc...The LS9 makes 638 NET HP and runs "hot." I call BS on "cool" running engines, this is NOT 1969.

LT1's are STOCK 180* thermostat, no need nor recommend a 160.

I don't know what you guys are talking about with LT1's running hot. My well maintained 50/50 mix of coolant/distilled water LT1 runs 190-194 down the highway with A/C on in 90* heat and humidity all day long.

Clean radiator/clean condenser free of debris, clean coolant, working water pump, t-stat, good hoses,etc....these cars DO NOT RUN HOT at all for a modern car. These cars are rolling Hoover's clean out your radiator/condenser.

Yes, the fans kick on late like 228 for primary and 236 or so for the secondary. Other modern cars have fans that kick on high too. GM kinda messed up by giving people a digital readout. How many do you see on today's cars?

Solution program on sooner or manual fan switch. I have the latter even when hot lapping during auto-x I never see about 210.

And that is the way it is...

1986coupe

Normal temps.

However, you will read a lot about manual fans, lower t-stats, and that sort of thing. If the car isn't cooling effectively you should first make sure the rad is clean. Also make sure the AC condenser is clean. Air needs to pass through both of these.

If temps are high and it is difficult to get the temps down then replace the rad. Fans move air but the rad is what does the heat transfer to cool the engine.

JrRifleCoach

Yep

Every spring/summer: air conditioning and overheating problems

Every fall/winter: blown heater cores and battery problems.

Almost as predictable as getting a oil thread locked.....

PLRX

Don't forget the "mice threads" during winter. I bet is the same people with memory problems.

JrRifleCoach

Are you saying I'm crazy and forgetful?!?

PLRX

No, you have never started a mice three three years in a row.

JrRifleCoach

I've been slipping lately, sorry.

230 degrees is at the upper end of OK

I'd worry if it goes over 245.

sunnfish

I had my engine rebuilt at that time the heads and block have been boiled clean. I have a 86. I bored it .030 over abigger cam headers removed all the pulution parts. I replaced the radiator with a bigger size ( more water to help cool it off). I replaced the water pump with a edelbrok higher gallons per minute pump. I bought a new double fan and took the old one reversed it and placed it in front of the radiator. When its about 85 out side the temp goes up to 235 then I stop and have a few beers until it cools off. If I can get to the xway and roll for a while it will come down to 210. I guess the way the radiator gets air is down on the bottum of the front fender. I would guess the asfault is about 500 or 600 when the sun is burning, so that air just don't help cool it down. I'm going to cut out the license plate and hope that might help. After that the fog lights and the parking lights are coming out. I also am going to put on a hood scoop to see if cooler air coming in might help. The engine cabin don't get much air. If that don't it i'll just have to stop and have a few beers until it cools off.