shtglouie

Hello everyone,

I just bought a Corvette yesterday. It's my first one.
It's a 76 L82 with an automatic 3 speed transmission.
From what I've seen of the exhaust everything seems to be Magnaflow exept the header (they seem to be stock and they are rusty). There is no catalyzer. I'll come back for the exhaust in another thread anyway.

Well so yesterday I pick the car up after a test drive last week.

The engine was rebuilt in 2008 and since that less than 1000 miles was put on the car.

I take the highway and quickly I see that the water temperature was going up... a lot...

I open the vent and put the heat in the car the engine is till hot ( nearly 280) So I get out of the highway and noticed that at 45 mph the temperature go down a little (2500)

Anyway I stop the car and go to grab a dinner so the car can cool down.

well I finally get back home. And check everything about overheating on the forum.

I think it might be the thermostat because the top hose going from the radiator to the thermostat is very very hot as the one on the bottom right of the radiator is not so hot.

Should I change the thermostat? Which one should I take?

a 180? what brand? Is it hard to change? Should I flush all the liquid?

Anyway I'll call the seller today after work. He was cool so I'm sure he is gonna help (plus he was a mechanic)

sstopczy

The fact that he was a mechanic would make me a little nervous that the car is overheating the day you bought it.

Does the car have the fan shroud and front spoiler to deflect air through the radiator? Link for spoiler: http://www.parts123.com/parts123/yb....5Z50000050G~~~ I would get new thermostat and drain the radiator and refill with half anti-freeze and half distilled water assuming the shroud and spoiler are in place and see how it does. If you are still having issues you'll have to dig deeper.

shtglouie

Yeah I've seen that one And I planned to get one after.

But normally the car should not need it as it is a stock engine even more with better exhaust than the stock one no?

What about the fact that the top left hose is really burning compare to the bottom right one?

Is it the symptom of something in particular?

PS excuse my english if there is some mistake it's not my mother language.

sstopczy

It seems like you are missing either the shroud or the spoiler which you do need for the stock engine. It came with both of them from the factory and they key to keeping the engine running at the appropriate temp.

shtglouie

Ok so I'll get that part! But you think that it can go as high as 280 degree F just because of the spoiler?

Maybe it's both!

I try to fix that and I come back to you!

!!

sstopczy

If you are missing the spoiler you are not getting the air moving through the radiator when you are at highway speeds.

speedreed8

the lower radiator hose should also have a spring side of it to keep it from collapsing when hot....

garygnu

was the cooling system bleed of properly ?the gauge could be off ,compare it with a heat gun .

PeteZO6

The guys are right about the spoiler under the front and the fan shoud. You need them both. BUT, I'm concerned that the car is running so hot - 280* is way over the top AND WAS DRIVEN ONLY 1000 MILES IN 5 YEARS. That's only 200 miles a year. Why was that? Makes me think the previous owner knew he had an overheating problem and didn't drive it much, and didn't or, couldn't, fix it. Now it's your turn
A Harbor Freight IR temp gun would be a useful tool to help you diagnose this. These cars do tend to run warm, but when the cooling system is operating correctly, they don't overheat.

Pete

bojvette

once you get this sorted out also put in a bottle of WETTER WATER * brought my temp down about 20 degrees & only around $6.00

shtglouie

well that was his wife corvette and she is 62 and doesnt drive it anymore that why he sold it.He as a 63 corvette too.

Anyway I called him and he will help me to see what's wrong.
but I will take those 2 spoiler to get the air going in the radiator and check after.

I'll let you know.

If I can't do it myself does anyone knows a good garage in southern connecticut?

By the way where is the water temperature gauge plugged in the engine?

76CSRvette

stock position for sending unit is in driver side head in between first 2 spark plugs starting from the radiator. Was the car spilling water or throwing smoke when it was overheating.

Jba750

Start by replacing the lower radiator hose (radiator out hose). Chances are the spring is gone and it is collapsing at highway speed (high rpm). Check it by letting it idle to see if it still overheats.
With mine, the vacuum advance was shot and adding to the problem because the timing wasn't advancing at higher rpm.

shtglouie

No water or smoke coming from the car.

shtglouie

The hose seems to be in really good shape they were put un 2009 when the engine was rebuilt

Jba750

Does it overheat at idle

shtglouie

Idle is when the engine is running but the car doesnt love right??

Yes it get really hot too. Just less quickly

Jba750

Might be a plugged radiator if the lower hose is cool but upper is hot.
1. Let it cool.
2. Remove radiator cap.
3. Start car and watch to see if the water starts to circulate. You should be able to see it moving around in the top of the radiator if it's not plugged.

Jba750

Could be a bad water pump. Look at the front of the pump, if there is water leaking out the front it's bad

shtglouie

No the water pimp does not leak. Tomorrow i'll change the thermostat and draines the coolant . Just to be sure before I get the spoiler

You have any idea how many gallons/liters there is in the circuit?

For the gasket on the thermostat should I used rtv gasket?