Radiator Question
 

Hi i need to refill the radiator on my 66 coupe 289 V8

I filled the radiator to to the bottem of the filler neck, started the engine with the radiator cap off to keep an eye on it.
As soon as the engine got warm I saw the coolant rise and it came flooding out of the radiator. I cleaned the mess up, let her cool down and when i looked back in the radiator i could not see any more coolant, it must have dropped below the grating.

2 quick questions
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Did i put in to much coolant ?
How do i know when there is enough coolant in there ?

Need some help here thanks.

RE: Radiator Question
 

Sounds like you filled it right, unless the 289s have some weird cooling system that I am unaware of. Fill it when the engine is cold, and run the engine for a couple minutes. You should see the level drop a little. Don't let it run long enough for the engine to get hot. Top off the radiator and replace the cap. Top off the coolant resivoir, assuming you have one, and that's all there is to it. After driving for a day or two check the coolant resivoir level, and top off as needed. If your car doesn't have a coolant resivoir, then run it for a few minutes while the thermostat is open, let it cool, and top off again.

RE: Radiator Question
 

You should be able to fill the radiator and let the engine run to operating temperature without any coolant coming out of the neck. The only thing I can think of that would cause it to come out like that is a leak in the head gasket causing pressure in the cooling system or there was no cooling fluid in the jacket and it caused it to back up when the thermostat opened up. I would try it again, let it warm up were the thermostat opens up. If the water come out of the neck, let it.. When all calms down, refill and make sure the water is flowing. You should be able to see it flow in one direction by looking into the neck opening. Then put the rad cap back on and let it cool down over night. Then open it up and see were the level is, you should still see it just above the row openings.

RE: Radiator Question
 

You most likely have air in the system. The system needs to be burped. Do what these guys recommend, and you should be fine. It will take running and cooling the engine several times for all the air to get out.

RE: Radiator Question
 

Also a thermostat is important. Not having one can allow too much pressure to build up and the water to flow through the engine too fast to cool it. Having one stuck closed is obvious, it will overheat.

You can add a burp valve to it if you still have issues. GM had them on some vehicles and I have seen them on some Ford trucks. Its stimply a T in the heater hose with a cap on it. remove the cap and air can escape the engine, put it back on and the water stays in. You can also do it cheap by pulling the rear heater hose from the fitting in the head, DONT DO THAT WHEN ITS HOT! There are other ways (not mentioned in this thread) to burp an engine but they take a bit more knowledge and could easily mess things up. So I wont get into it here.

RE: Radiator Question
 

after the t-stat opens, have some body hold the rpms at about 1500 and fill it till its full and put the cap on, then let idle and your done

RE: Radiator Question
 

as for the thermostat, 180* minimum....and look for a butterfly valve one, they fail open!

RE: Radiator Question
 

The recovery system is a must I think. Fill up the radiator, fill up the recovery bottle/jug, get the engine hot enough to open the thermostat with the heater on. Let it idle awhile, then turn her off and go get a good night's sleep. The next day check your recovery bottle and fill the recovery bottle again , and repeat the above process. After doing this for 3 or 4 times, all the air will be out of the system.
Yeah, the 180 degree thermostat is the best degree. Also, use a 13 lb. cap.
Once you get all the air out, and your heat gauge is stable, only put enough anti-freeze/ water mixture in the recovery bottle to fill to the Cold line.