Running Hot (help) ?????
Thread Starter
Instructor
Joined: Apr 2003
Posts: 221
Likes: 0
From: midwest Iowa
Running Hot (help) ?????
We have a 1986 vett it seems to me its running hot ?? to day in traffic the temp was runninig 240-248 is this normal or sould I be looking into somthing Thanks 
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Most likely your radiator has debris in it which reduces the airflow and it ability to cool. One fast thing you can do is to hold the fan blade and blast water from a garden hose backwards through the radiator. If that helps, a much better cleaning should be done by taking the radiator shroud off and vacuuming and picking the debris out of the front of the radiator. Normally in summer weather a stock 86 in under 35 mph speeds or at stoplights will go to 238 F and the main fan will come on. When you get underway (35 mph or higher sustained), the coolant should drop to the opening temperature of the thermostat. The stock stat is 195 F. GM says to shut the engine off at 260 F and let it cool down.
Race Director
Joined: Jul 2001
Posts: 14,604
Likes: 3
From: Glendale, AZ
Originally Posted by jfb
Most likely your radiator has debris in it which reduces the airflow and it ability to cool. One fast thing you can do is to hold the fan blade and blast water from a garden hose backwards through the radiator. If that helps, a much better cleaning should be done by taking the radiator shroud off and vacuuming and picking the debris out of the front of the radiator. Normally in summer weather a stock 86 in under 35 mph speeds or at stoplights will go to 238 F and the main fan will come on. When you get underway (35 mph or higher sustained), the coolant should drop to the opening temperature of the thermostat. The stock stat is 195 F. GM says to shut the engine off at 260 F and let it cool down.
check this thread to see what EXACTLY he is talking about, about the debris
http://forums.corvetteforum.com/show...65&forum_id=48
Safety Car
Joined: Nov 2004
Posts: 4,991
Likes: 5
From: The Pines South Jersey
if yours has an aux fan it should be runnning at that temp also, you can check that by grounding the lead going to the sensor located between 1 & 3 cyl squeeze it to get it off and stick your probe in there and ground the other end of the test light.
Thread Starter
Instructor
Joined: Apr 2003
Posts: 221
Likes: 0
From: midwest Iowa
Thanks for all the info I will remove the rad and clean it I was just telling my wife that I dont recall the fan comming on I will check this in the morning thanks alot for all your help
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Team Owner
Joined: Sep 2001
Posts: 62,153
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
The main fan comes on at 228, the aux fan in front of the radiator at 238F.
More than likely you have road debris stuck between the condensor and radiator. You'll have to remove the shroud to get it out, and you MUST do it this way, no halfazz spraying from underneath because it wont get it all.
You should also flush out the old coolant, be sure to put green coolant back in, and replace the thermostat. You may go down to a 180 thermo, since you live in Iowa I wouldnt go with a 160 thermo.
More than likely you have road debris stuck between the condensor and radiator. You'll have to remove the shroud to get it out, and you MUST do it this way, no halfazz spraying from underneath because it wont get it all.
You should also flush out the old coolant, be sure to put green coolant back in, and replace the thermostat. You may go down to a 180 thermo, since you live in Iowa I wouldnt go with a 160 thermo.