I have just completed a valve job on my 85 Eagle wagon. I don't understand why it is running hot. I have installed a new temp sensor. It runs pegged at the top within a few minutes.
Also there is a sensor of some type horizontaly mounted in the intake manifold behind the carb. I have traced that wire over to some kind of relay block on the passenger side of the front fender below the hood hinge. Anyone know what that is for? Does it work in conjunction with the sensor on the back of the head? This car did not overheat before I did the valve job. Confused.
That relay is probably for the intake heater underneath the intake manifold. Does run fine or does it run like it is overheating or are you just going by the gauge? I'd check the sender to make sure it is working properly. Did you put a bunch of sealant or teflon tape on the sender?
perhaps he is having a bad head gasket and water is leaking to the combustion chamber that can cause the overheating
I think it sounds like a faulty sender. I had one do exactly the same thing, but when I checked with a thermometer in the radiator, it was just under 150 after running for 10 minutes from a cold start. Of course it's just a guess, but I would check the actual temp if you can just to be sure it is malfunctioning. Yes, that is the intake heater with the relay but that would not cause an engine overheat. Fan clutch, clogged radiator, worn water pump vanes, or a thermostat stuck closed will all cause an overheat condition. But I would start with a replacement sender as they are cheap and can be defective. Let us know how you make out.
I can see that the gauge reacts to the thermostat opening. I did use teflon tape on the threads. It seems to be running hot. I shut it down when the temp gauge gets above the green area. I can hear it bubbling in the overflow bucket. It has sucked fluid back into the radiator as it is designed to do so maybe it just has an air pocket yet or something. Hopefully the head gasket isn't the issue. Is there some way of knowing that?
It runs like it used to. Always has a bit of a studder sound to the exhaust. I figured that was from the carb and vacuum lines in it being "not so good". I have suspected fan clutch. Is there some way of knowing if those are bad?
I will see if I can get an actual temp on it. I think the thermostat was for 190 degrees. I think that was the only one they listed?
The relay for the intake heater is gone actually. There are two which appear to "plug in" to a socket and where those wires are coming in there is no relay. What is the other one for? I can check voltage at the wire with my VOM to see if it has voltage. Thanks for all the good ideas. I will keep you posted.
there is a simple way to test that head gasket by using a compressor and charging some air into each cylender if the radiator bubbles then you have a faulty gasket,hope this help
Please either rrun your compressor down to say 15 psi. or if possible regulate to 15. i do not like your teflon tape whatsoever. its pipe thread and needs nothing more than tight enough not to leak.
How did you make out with your overheating? A bad head gasket is easy to spot if.... You have coolant in the oil, or your cooling system gets over pressurized from cylinder compression leaking past the fire ring of the gasket into the cooling passages of the head, or LOTS of white smoke/steam out of the tailpipe. Late ignition timing may also cause it to run hotter, not a cause of overheating, but may contribute to the problem combined with another malfunction.