Over Heating

[Jeff 69]

I have a 1969 Road Runner witha 383 motor.The motor seems to overheats seconds after the car is started.
well maybe 5 min after starting. I replaced the rad cap and the thermostat (180 ).The water in the rad seems not to be moving. The water pump does not make any noise or does not not leek any water.Can any one help me?

thanks Jeff

 

[69hemibeep]

Have you run it with the cap off and if so were there any bubbles? Is it getting hot and boiling over or is the guage just saying its hot, and what kind of guage? My first thought was waterpump

 

[Roadcuda]

Also, with the cap off you can see the water flow once the thermostat opens up, and of course the upper hose will heat up once the water starts flowing. this is how I would check both the thermostat and water pump operation. Sounds simple but it works for me!

 

[steve.f]

Hi Jeff, had similar problem on a 383 ended up being the empellers were installed backwards on a cheap water pump
Good luck,Steve

 

[BahamaA12RR]

Has the radiator ever been repaired or recored or is it original?

Did you have the heater hoses off and put them on reversed?

Does it have the stock fan on it or aftermarket?

What about the radiator shroud? On or off?

 

[Jeff 69]

The over heating, The fan shroud is on the car,and is stock,the rad cap was off and no water was moving,and I saw no bubles. After just a few min ( 3 or 4 )The water comes out of the rad. Also the water pump does not make any noise, So I just though it might not be that. I did not look at the temp gauage in the car .

Thanks

 

[Moparnut]

Remove the thermostat and put everything back together. Leave the radiator cap off and see if the water is moving, you can narrow things down like that. I've seen the lower hose collapsed and not letting water flow, some of the real cheap hoses don't have a spring. Once you get it figured out Mancini Racing sells hi flow thermostats, they have a larger opening and allow more fluid to pass through. I use them on every mopar I build and have had good luck.

 

[69hemibeep]

These things like about half to 2/3 of the upper tank filled when cold or they will pee every time you turn the engine off, I call it marking their territory. If you had the tank completely full with the cap off the water is going to expand and push out of the tank before the stat opens, the cap helps prevent the fluid from boiling by pressurizing it. I don't know your automotive background and I don't want to insult you,but these are some basics. So if it was not overfilled and did this I would run it without the stat as mentioned above to check flow.

 

[george68hemirr]

what they said

 

[A31PKG]

I have a 1969 Road Runner witha 383 motor.The motor seems to overheats seconds after the car is started.
well maybe 5 min after starting. I replaced the rad cap and the thermostat (180 ).The water in the rad seems not to be moving. The water pump does not make any noise or does not not leek any water.Can any one help me?

thanks Jeff

Did this happen all of a sudden? Or after you did something, such as replace a component?

 

[Jeff 69]

I took the thermostat out and the water flows very good, and no over heating.This will be the 3rd thermostat I have put in in this car. I will get the bigger thermostat this so I have no more problems. I just want to say THANK YOU ALL for the help. :grouphug:

Jeff

 

[george68hemirr]

I took the thermostat out and the water flows very good, and no over heating.This will be the 3rd thermostat I have put in in this car. I will get the bigger thermostat this so I have no more problems. I just want to say THANK YOU ALL for the help. :grouphug:

Jeff

drill a small hole in the thermostat so air can bleed itself from the system......jack the runner up high on the front/driverside where the radiator cap is and keep adding water/anti-freeze until you see no bubbles in the radiator....then she full is....