96 coupe: cooling? Is this right?

[SQLDBA]

Hello. I am new to the Vette world. I just bought a 96 coupe. Black / tan int. Very clean car. 81k mi. I really just want to know if these gauges check out. The temp outside was about 90f and I had driven the car for about 35 min or so. The coolant analog gauge looked a bit high to me. It was right on the 2nd mark after 185. Please see the image below:

Thanks.

 

[Ken]

No problem there; the engine's are designed to run much hotter than that.

 

[SQLDBA]

No problem there; the engine's are designed to run much hotter than that.

:L You'd think that GM would've made a gauge that went to 280 then? Is 260 just an idiot light number or is that when the car will really start to see mechanical problems? I was just worried cause the analog gauge looked really high to me.


Thanks for the quick reply. BTW what forum software is this? It is very well put together but looks like PHPBB.

 

[Ken]

The coolant analog gauge looked a bit high to me. It was right on the 2nd mark after 185.

I'm confused? Now you say that you're seeing 260° in the picture somewhere? :confused

Here's a link to everything you ever wanted to know about the LT1 Reverse Flow Cooling System.

Edit: I see the reading now. 228° is not really that uncommon to see in traffic, on a warm day.

 

[Ken]

... looks like PHPBB.

PHPBB it is.

 

[EricVonHa]

In the LT1/4 Vettes there are TWO different temp sending sensors. One is on the front of the water pump and the other is on the pass side head between cylinders 6 & 8. I seem to remember the head sensor is the one that drives the analog gage because... if there are any air bubbles in the coolant system or the thermostat gets stuck (I've had both) the analog gage will read very high (much higher than the digital).

The analog gage is difficult to read.. but once you get used to it, it'll be "cool" Check your upper coolant reservoir just to be sure also.

 

[jmccloud]

260 degrees

260 degrees is an important temp because that's where the 50/50 water/antifreeze mixture boils with the designated pressure cap (17psi or so).

 

[SQLDBA]

I'm confused? Now you say that you're seeing 260° in the picture somewhere? :confused

Here's a link to everything you ever wanted to know about the LT1 Reverse Flow Cooling System.

Edit: I see the reading now. 228° is not really that uncommon to see in traffic, on a warm day.

No sorry to confuse you. I was just saying that the analog gauge looked much higher than the digital. You had said that the temp looks fine and I just took that as maybe the 260 is not an important number. jmccloud answered why the analog gauge maxes at 260 though.

Anyway, thanks to everyone who replied you all gave very useful info.

 

[chuckh]

95 with similar story

I recently bought a 95 LT1. I too was concerned about how hot the engine seemed to be running. On a day of moderate temp (60 F) and moderate driving (30-70), no aggressive acceleration, no long idling), it hit 252. I then slowed way down and it dropped down to the 230-240 range. I was told that "they run hot". So, beyond boiling at 260, how hot should it get before being concerned that there is a problem?

 

[1995 RedVette]

I have a 95 with 103,xxx on the clock and the highest I have ever seen it is 230 on the digital read out. At that point the electric fans came on and the temp droped like a rock. I was setting in traffic at the time with the A/C off about 75 degrees out side. When I have the A/C on .... I have yet to see above 205 setting in traffic with the air on high.

That said, the analog guage on the right side of the cluster has always read higher than the digital (about 20-30 degrees). I have never had a problem with the car running hot (i.e. having coolant boiling into the overflow tank, or smelling an overly hot engine or coolant) I just figured that the sender on the analog guage was a little off and never worried as long as the digital temp guage stayed in a reasonable range and I saw no evidence of the car running hot.

Brett

 

[chuckh]

Problem solved

Thanks for setting the standard. I ended up pulling the radiator and found lots of debris in there, effectively giving me half a radiator. After removing it and carefully cleaning out the A/C condenser, it now runs somewhere between 190 and 210. Much more as expected. I don't know where the previous owner was driving to pick up that kind of junk.

 

[Ken]

... don't know where the previous owner was driving to pick up that kind of junk.

It's common to find that area loaded with debris. One should make it a habit to check and clean that area once a year or so, depending on what the environmental conditions are that the car is driven. If you live in an area that has a lot of leaves on the ground in the fall for example, it's wise to check it more often.

Glad to hear you found the problem.

 

[94C4]

Cruising on the highway my 94 LT1 runs at 190. slow, in town driving will make the temp rise to 228 where the fans kick in. It then goes down right away. I would be concerned with temps over 240 though.

 

[ShaneL]

My usual temp is192 degrees in city with the AC on (causes fans to turn on). With the AC off the fans will not turn on until the coolant reaches a certain temperature (I do not know what it is).

-Shane