Hello, I seem to be having some overheating issues. The 61 with a 170 engine I'm working on has a new 2-row original style radiator, new water pump, new hoses (bottom hose with spring), new temperature sender, and a new 180 degree thermostat (replaced twice). After I finished installing all the new cooling system parts, it seemed like it was running really good. Drove it around a local town for several hours with no problems......needle on temp gauge stayed right in the middle. Last time I took it out it overheated in about 4 miles. Also now when I just let it idle for around 10 minutes the temp gauge pegs out. Not sure what it could be.....I feel like I have checked all the cooling system parts 2 or 3 times now. Things I have tried: -I've cycled/burped the cooling system several times, so I don't think its trapped air. -I'm on my second thermostat. Replaced the first new one, thinking it might be defective. -Checked fan belt tightness. -I can see the coolant moving around in the radiator when it is running with the cap off. So I know that the stat is opening up. -Adjusted timing. Made no difference. Other info/observations: -When the gauge is pegged out, the radiator doesn't really boil over or spew out any coolant. It really just steams a bit, like a cup of hot coffee. -I thought I might of had my oil overfilled but it turned out to be ok...but I did notice the fairly new oil was already black and smelled a little like gasoline. -Coolant and oil seem to be free of contamination, so I don't think its a blown head gasket. Ideas: Could it be a dying oil pump or clogged pickup tube? Maybe the carb is running lean? Any info or ideas anyone has would be greatly appreciated. Thanks, Andrew
Try another gauge just to confirm, mechanical if you can. If your gauge is pegged, but it's not boiling, might not be accurate.
If you put the wrong length bolt for the water pump in, it will crack the cylinder wall on that engine!
If the gauge is pegged and you have the cap off and it isn't spewing coolant and scalding you in the process the gauge is off. I saw that on my buddy's Model A with a small block and Walker radiator in it. the gauge read 261 degrees F but he could stand in front of it with no shirt on and not get a drop of hot water on him when he took the cap off to show the Walker rep. Temp probe showed that it was running just about 1 or 2 degrees above the rate of the thermostat. They sell thermometers that have a probe that you stick in the radiator or AC cooling duct that look like a candy thermometer with a thinner probe at most parts houses or Sears or other automotive tool supply outlets for a few bucks that are simple to use. That's a real simple way to tell the actual temp of the coolant while the car is running. Fire the car up with the cap off the radiator and don't pull it off when it is hot though . On the oil looking dirty quickly some oils just do that especially when they are a high detergent oil in an old engine if you haven't had the car long. Gas smell in the oil= you may have a carb that is leaking when the car sits or runs and be getting raw gas down in the cylinders and on into the crankcase and oil. You have to give about an 80.00 deposit on it but AutoZone has a radiator pressure tester kit that you can test the cooling system to see that it holds pressure and doesn't have a leak. A no brainer to use and worth the time and trouble to go get it, test the cooling system for pressure and take it back and get the deposit back.
Thank everyone for the good info. Definitely have some stuff I need to try, getting something to read the real temp of the coolant might be my best bet. -Andrew
Aw, just drop a SBC in it. No more worries! [emoji12] Sent from my iPhone using The H.A.M.B. mobile app
Try one of these infrared units. Both mine read within a couple 10ths of the really expensive Flukes. Can read tstat housing, top and bottom of radiator, and the grill temp to do burgers. 20 bucks. https://www.amazon.com/Etekcity-Las...8-2-spons&keywords=infrared+thermometer&psc=1
What is your coolant/water mixture, and don't say that it is straight water. I am still running the 144 that my '60 left the factory with. I am also still running the radiator that it left the factory with, for real. My shroud is missing, and has been, since long before I got the car. It has a 180º thermostat, with a 3/32" hole drilled near the top edge. I recently replaced the water pump, as the front bearing finally let go, even without leaking. The temperature gauge never goes past the middle of the gauge, even though the radiator makes some noise when hot. It did kick out a little coolant and steam after the last time I changed the coolant, until it reached stasis. That appears to be, when viewed, cold, with the cap is off, where the coolant is just above the ends of the tubes, by about 1/2". It has to have room to expand when hot. It runs fine all-day like this, at 65mph, or bumper-to-bumper. The notions of the carburetor running lean and the oil smelling like gasoline are diametrically opposed to each other. If you are getting wash-down of fuel in the cylinders into the oil, it is because there is too much fuel. Pull the #6 spark plug and the #3 spark plug, which, on this engine, will have the broadest difference in mixture, due to the manifold design, and post a picture of each, denoting which one is which. That will rule out/in fuel issues.
I'm going to get a temp gun. Seems like a good investment at this point. Coolant/water mixture is pretty much 50/50. And I used distilled water. I will pull the spark plugs that gimpy mentioned and see if I can get pictures. Thanks again! -Andrew
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