[Amtcoastie76]

Was driving to work when my engine started clanking and smoking and when i could noticed that there was almost nothing left in the radiator coolant wise and had all come out of the drain line. the coolant is new, hoses are new, thermostat is new. The cap looks old and the radiator is not the best but it does hold coolant. so what could cause this?

65 389

[Amtcoastie76]

Was driving to work when my engine started clanking and smoking and when i could noticed that there was almost nothing left in the radiator coolant wise and had all come out of the drain line. the coolant is new, hoses are new, thermostat is new. The cap looks old and the radiator is not the best but it does hold coolant. so what could cause this?

65 389

[David Jones]

Do you have a temperature gauge?

http://kurtspontiac.homestead.com/DavidJones69GTO.html

[goathead68]

My guess? The old radiator cap can't hold sufficient pressure, which will cause the coolant to boil. Pressurized coolant has a higher boiling point than non-pressurized coolant. Boiling coolant soon escapes from the overflow tube. Eventually the boiling coolant turns to steam. Steam is not a good coolant. Motor begins to really overheat, starts making noise and smokes. Eventually dies because it's too hot.

A correctly operating cap will raise the boiling point of the coolant quite a bit over the boiling point of water, which is 212 degrees at sea level. New radiator caps are cheap ($5-10). New engines are not.

Hopefully the engine isn't hurt too badly. I had a thermostat stick in my old Olds 442. Pumped the coolant out, motor overheated and seized. Dumb me did not have a temperature gauge in the car, just an idiot light (hence the name). Got the car towed home, let it cool down, replaced the thermostat, refilled the cooling system and started the engine. It rattled pretty bad (I suppose I cooked the oil real good, so good it didn't flow too well), but once the oil began to lubricate, the noise went away. Put fresh oil, a quart of Rizlone and a new filter in it. Engine was fine after that. I was real lucky!

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[HUMBLER]

What is Rizlone?

"The Humbler is here, this is the way it's going to be baby!"

[mike nixon]

rizlone's an oil additive that is suppsed to free up sticky lifters and add lubrication. it's kinda like marvel mystery oil.

regarding the overheating, if the hoses and stat were just changed it's possible there was an air pocket still in the engine.

the cap's also a possiblity.

i'd look into adding an overflow tank to the car with an upgraded cap.

also as mentioned above if the car has lights in the cluster i'd add a set of guages so you can keep and eye on things.

mike

[gpnut]

I recently added an aftermarket overflow tank to my 71 GP. Got it at Advance Autoparts here in NY. May be carried by other large chains. Cost between 7 and 10 dollars depending on size.

At least my family and friends no longer complain about puddles in their driveway on hot days!

[Amtcoastie76]

I think the thermostat is bad beacause it overheated again with a new cap at idle, so i replaced it and drove it so far so good, oh and what is the temp sensor called that you attach the wire to to get the temp called?

[Trans-Formula II]

I also have the same problem, when running the highway at 3500 rpm I run hot and when immediately shut off the coolant comes out, slightly, I have a 16 psi cap on it, is 20 or so better?

http://members.cardomain.com/ironinjun68

[goathead68]

amt asks: 'what is the temp sensor called that you attach the wire to to get the temp called?'

amt,
It's called the temperature sending unit. Your local parts store should be able to get you one. You may want to look into installing mechanical gauges sometime down the road. I've found them to be much more reliable than the electric ones. I use Auto Meter gauges in my GTO.

ironinjun,
I think the stock cap should be 15 or 16 lbs. A few questions for you;

What temp are you running at 3500 rpm?

Have you had the cap tested? It should hold the 15 lbs. and not leak down at all.

I'm guessing that your coolant level may be a tad too high. It should be about 2" below the bottom of the filler neck when the engine is cold. My car used to weep a little, too, as the radiator was too full. I put a recovery bottle on it and now it's fine.

humbler asks: 'What is Rizlone?'

First of all, I spelled it wrong. It's supposed to be 'Rislone'. I used this stuff quite a bit in my older cars. I had a '73 Nova that would always tick if it was abused too much. I started using Rislone to free up the lifters. I'm guessing that they were slightly varnished. Mike is right, it's like Marvel Mystery Oil, it cleans deposits and lubricates. My dad was a mechanic for 44 years and he swore by this stuff, and I'll be darned if it didn't work. By the way, he uses STP oil treatment as assembly lube, too.



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