Topic: engine temp
in Forum: C3 Cooling and Heating Systems
Already a Member?
Click Here to Login
Not yet a Member?
Click Here to Register for Free!
Hi All,
If my engine temperature is running at close to 240 is that running close to overheating? the engine isn't smoking or anything. I have a 1976 vette with 350.
Thanks!
Darrell
SPONSOR AD:: (Our Sponsors help support C3VR)
Lifetime MemberEquinunk, PA - USA
Joined: 10/31/2007
Posts: 2466
Vette(s): 1972 conv, 4-speed, 350, 200hp, numbers match, rally wheels, war bonnett yellow w/white top. good condition, nice driver.
Seems a tad high. Check T/stat.
Former Member
Send PM
Frederick, MD - USA
Joined: 9/8/2003
Posts: 3398
Vette(s): 1969 convertible L71 427/435 4-speed black interior
First...make sure it's actually running that hot. You could have a bad temp sensor or bad gauge. Once you know that, you can check the more basic areas...
Gunslinger 2011-02-18 07:54:01
Coolant level.
Will the system and pressure cap actually hold pressure?
Stuck thermostat?
Under what conditions does the car run that hot?
idling?...bad fan clutch
at highway speeds only?...bad lower radiator hose (spring missing) or air deflector missing, no seals around the radiator
all the time?...bad seals around radiator, low coolant level, bad thermostat, engine timing wrong, radiator cooling fins could be clogged, fan belts loose, bad water pump
Check your oil level and see if it smells like coolant...that could be a blown head gasket or cracked cylinder head. You can also smell the exhaust and see if it smells like coolant.
Hopefully your problem is very simple. Just go from the basic to more advanced to determine the cause. You don't want to spend lots of time and money when the problem is simple.
Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
I would suspect the gauge is not telling the truth also....
IF the engine was indeed running that hot, it would be puking coolant all over the place, and the engine would most likely be trying to seize, and run like crap. I'd be inclined to believe the temp sensor is skewed a bit, and not giving the proper signal to the gauge, tho the gauge itself could also be bad.
Does the temp gauge start out at the correct temp when you first start it?
IF the engine was indeed running that hot, it would be puking coolant all over the place, and the engine would most likely be trying to seize, and run like crap. I'd be inclined to believe the temp sensor is skewed a bit, and not giving the proper signal to the gauge, tho the gauge itself could also be bad.
Does the temp gauge start out at the correct temp when you first start it?
Joel Adams
C3VR Lifetime Member #56 
My Link 
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
I hafta wonder if there is an air bubble in there that is 240 degrees, which is giving your temp sensor that reading when the coolant/engine temp is actually less.
It came to mind so I thought I'd put it out there.
Kevin
Lifetime MemberHOWELL, NJ - USA
Joined: 5/18/2004
Posts: 6812
Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
Are you sure you don't have a bottom hose closing and straining the system? If your bottom hose doesn't have the spring in it, that could be a high temp culprit as well. Happened to me. Switched to a hose with a spring and now she runs at 180!
LukesVette Homepage
Veteran of Operation Iraqi Freedom
101st Airborne(AirAssault!)
God Bless America
Support Our Troops 
I bought one of those laser temp gauges and it is showing my car is running at 180. Do you know how accurate those gauges are? Also I am looking into buying an aluminum radiator on Ebay. Do you recommend buying such an item for there? Thanks for all your help!
Hey Darrell,
Last Spring I got an aluminum radiator off of E-Bay from Leadfoot Racing -- $200.00 plus shipping. It took me a while to do the install myself, but if I can do it anyone can.
The biggest problem I had was the slightly thicker aluminum rad. caused me to have to trim the 4 bumpers that hold it in place. I think the aluminum radiator is an excellent upgrade for any of our C3's. Go for it!In the meantime, check that bottom hose like Paul said. And look around at past threads for ideas on what your current trouble is.
Kevin
I believe those laser temp guns are accurate I have one and used it a few times. you would want to point it at your thermostat housing should be your operating temp. then point it at the temp sender see if their is a difference.
in Forum: C3 Cooling and Heating Systems
SPONSOR AD: (Our Sponsors help support C3VR)