The Skylark's been running way too hot as of lately. For a while it was leaking everywhere out of a bad gasket on the thermostat housing. I replaced the thermostat with a icy 169 degree one, and redid the gasket, but its still having trouble. I got home today after a 20 minute drive on the freeway in 90 degree heat, shut off the car, and got out, and realised that coolant was literally gushing from the overflow. At least 2 gallons boiled out before it was done. Any ideas? This is probably pretty elementary, but so am I, so bear with me. Mike '66 Skylark 340-4
Keep in mind that I'm a dummy... is there a way I could confirm that's definately the problem? If it is, how do I go about replacing it? ~Mike '66 Skylark 340-4
Hey Mike.Well..As you know it could be a number of things.How is the rad?? Are the core fins all there and intact?? Check down at the bottom of the rad.When it`s cooled down and with the cap off check the coolant passage tubes.Are they crudded up hindering flow?? Is the new stat good?? Other than that you will have to go through all the cooling system components. Later,Tony.
How old is the radiator? Is it restricted? Let the car warm up with the cap off. Once the stat opens, you should see coolant flowing out of the cores pretty rapidly. If the radiator is old, I would remove it and take it to a radiator shop. Have them boil it out and check the flow. If your running a 3 core radiator, be careful of using 160 degree T-stats. Your car can sometimes run hotter with a cooler t stat. The cooler thermostat doesnt allow enough restriction in the system. The coolant goes thru the radiator too fast, not allowing it to cool down. Like SteetStrip said, also check your fan clutch. The clutch should feel somewhat stiff. If your able to get more than one revolution of the fan by spinning it, or if there is play in the bearing, replace it.
If the fan and Rad are original I would suspect them both. Good idea to have the system flushed. Probably time for a new fan n e ways.
Don't forget to inspect the cap itself!! If the rubber gasket in the radiator cap is bad, you could have symptoms of boiling over.
