CStewTAMU

If the water pump is good, the tstat is good, the fans are in working order,etc. Take the radiator out and clean it. Then take it to a radiator shop and let them clean the core out.

I just did that to my 94 today and the differences are profound. The bottom half or so of the tubes in my core were clogged. And the the fins were full of grass and dirt.

I just took it for a spin and let it warm up. It ran much cooler...even idling. Even went to the drivethru and left the engine running. Never even got over 185 sitting idling in the drive thru.

dchoran

THANKS jfb, my mind is at ease

VinceC4

Mine runs cooler with the A/C on...go figure

dchoran

I thought i read in another thread that what you state here Vince is EXACTLY what is suppose to happen when the AC is turned on in an '84.

Sounds bizzarre for sure.

Maybe some veteran forum member can explain????

THANKS.

dave H.

born2corner

several months ago i tried my darndest to shed some light on the fact that the L98 is very capable of running extremely cool even w ac on , stuck in a drive thru.. i also let many of these fellow members that i had 22 yrs as a master tech,, finally buying a vette after working on these truck motors for twevty yrs.. i had a few tricks up my sleeve and played around w my vette til it ran perfect..i was able to get on this forum and relay some killer numbers coming from multiple sources; my snap on scan tool,, an infared gun,, and my trusty old factory dash is only one degree off of the scan tool reading...i got this nailed down w proof ,, performance is day and night diff when the old truck motor runs 30 degrees cooler.. call me fellas,,, be happy to school ya 704-492-8355...kelly lindberg

aquablue96

Had to reply to this one because ever since the day I bought mine 2 years ago it ran in the "red" on the analog gauge and 240 or more on the digital in traffic. I had the thermostat replaced and radiator flush. Didnt help, took it to my mechanic this year and asked to have the area in front of the radiator cleaned out (bottom suckers) and got another thermostat (they always assume it is that) before he finally did exactly what we suggested. Anyway, as said many times before on the forum, if you have tried everything else and still running hot, check for major debris in front of your radiator. After two years I drove mine to work this morning and never got above 180!

ARMAN72

My 93 runs about 190 out on the highway.....but is stop and go traffic or in line at the drive thru of B.K. it will hit 210-215 even with AC on.. I asked about this when i 1st got mine everyone said it normal. I have clean out the leafs and stuff in the front and all that and it still does it.....

IrishJoker

Cool doesn't necessarily mean efficient. Old school would say 180 - 190's is the temperature range for a small block. New school would say 200 - 220. All I can say is I have an L81, LT1 and a LS1 and they all run in the 200-210 range for normal operation. GM says this is where they should be - btw around 210 with AC on at hwy speeds and 220 in stop and go traffic.

born2corner

gm wants your vettes running as hot as possible,,it keeps cars in the shop..lets not forget one critical thing;---cool is efficient period,,old school,,new school,,why do our hot rods have so much more power on cool dry day as opposed to todays heat and humidity,, why do turbos work better w intercoolers??? i have countless magazine articles saying vette engines run better cooler...seems to be some guys on here that missed school the day they taught that heat runs to the cold simply meaning 160 degree t stat,,,,a large capacity radaitor,,which comes stock on vettes,,and runnin the fan manually can keep ur temps very low increasing performace....guys ,, these are facts

wnafly

100%

ol school

with a new radiator my 96 still runs 235 in traffic never has left me stranded but after 3 yrs of this it still makes me nervous, but like everybody say on here its normal...

Moto1

I understand that some of the later c4's have auxilary fan that I believe is for the A/C. All the 84's Iv'e seen have only one fan. My 84 in a garage without the A/C on (98 degrees ambient) at idle for about 15 minutes will go around 195 at the highest. Turn the A/C on and it hits 220 and seems to keep rising. I have replaced all of my cooling components and my condensor/radiator area is clean as well. I have flushed the block twice The low side of the A/C is 40 pounds and the High side is at 250 pounds which should be normal. The cat is hollowed out and there isn't any EGR on the car. It may be normal, but being that the tempature never realy stabilizes is what gets me. Temp switch was replaced as well. I even went as far to place a white mark on the water pump pulley and track it with a timing light with the A/C on and off to verify the belt wasn't slipping -new one of those too. I don't know....

born2corner

i feel for you guys whos temps average over 200 . being a long time mechanic all these yrs,,finally get to work on my own vette,,,high temps on such a motor that easily blows head gaskets if ran low on coolant,,scares the crap out of me because runnin 200 or even higher,,leaves little room for error..only time corvettes came into shops i worked out of was because cooling system bursting everything in its path customer not knowing the gaskets or heads hurt..you guys should look me up...great feeling never ever seeing temps over 180 any moreand always dropping towards 165-175 which is what my vette now averages no matter what,,,doesnt take a genious to accomplish these temps...determination to find every ounce of hidden stock power is how this panned out,,,couldnt be happier w my stock truck motor that feels like true 350 w just few tricks

born2corner

hey fellas , forgot to mention the fact that my air valence thats designed to pull road air to the rad. ,,is completly missing the centermost portion..after i install a new one i wont be anticapating cooler temps by any means,,however the valence will most likely allow me to shut my fan off more frequently

dchoran

I'm no mechanical engineer (actually chemical) but a combustion engine is a combustion engine is a combustion engine.

My Harley Ultra is air cooled - on a 100F day sitting in traffic it gets up to 240F oil temp.

So what is the issue with a 240F water cooled engine where the oil temp never goes above that??? Yeah, performance may suffer a bit, and gaskets may erode quicker, it may "smell" hot, etc......

The PO of my '84 brought it into a GM dealer and they said everything was normal.

GM even states overheating is defined as: 299 oil temp / 255 coolant temp.

Do you think the GM engineers picked those numbers out of a hat???

And it is not unusual for analog/digital gauges from the EIGHTIES to be off +/- 20F degrees (or +/- 20%) - that is a fact.

Maybe it would have been a better design for all us Vette folks if GM had put in these instead - that way we'd have NO CLUE what the "actual" temperature was

Moto1

"Maybe it would have been a better design for all us Vette folks if GM had put in these instead - that way we'd have NO CLUE what the "actual" temperature was "

That's hitting the nail on the head. I had thought about leaving the switch on volts instead of tempature and let it be. I'm still waiting for someone to state "Mine runs 230 all the time, no worries" Thanks for everyones input.

dchoran

"Mine runs 230 all the time, no worries"

There, I said it.

Dave H. Appleton

brian84

when my 84 decides to start, it runs 180 coolant / 190 oil all day long.
nightmare traffic puts me in the 206 / 215 coolant mark.

but - I have a huge mouth air dam that I made from some sheet aluminum due to my car missing every piece of factory duct work for routing air flow to the radiator.
here is what I ended up making for about $20 at lowes.

before supports were added :

Moto1

Thanks for jumping out there Dave. Brian that's not a bad 20 buck solution. I have thought the front ground effect on mine would improve airflow to the condensor/radiator. I may install some flashing right behind the opening to direct the airflow better.