Mystery overheating

[BAsque1]

I topped the tank yesterday and left it uncapped, the level was checked this morning and the level has not changed. I hope that this means all air is out. Later on I will start the car for 3-4 minutes and then cap it and observe what happens. Will inform later on of the results. I will have to disconnect the by pass and reconnect the temp sending unit again. Keeping fingers crossed.
Lou

[Detroit Bill]

Originally Posted by BAsque1

I topped the tank yesterday and left it uncapped, the level was checked this morning and the level has not changed. I hope that this means all air is out. Later on I will start the car for 3-4 minutes and then cap it and observe what happens. Will inform later on of the results. I will have to disconnect the by pass and reconnect the temp sending unit again. Keeping fingers crossed.
Lou

Did you run it like that or just let it sit?

You have to run it for a while. You want the thermostat to open and let the flow fill or Carry the bubbles out.

[Blas]

Take the thermostat out of the car and see if the problem persists. As was mentioned earlier, installing the thermostat backwards or if there is an interference with its opening due to its design, it could also be faulty. Taking it out removes it from problem statement.
Thermostat should say "Engine Side" on it and should have a weep hole in the plate body, hole should be orientated in the top position when installed. Drill on 1/8" hole if it does not have one.
If this is an option for your engine: Get a "Balanced Thermostat" designed thermostat. I believe they fail open.
If your fan temp switch is similar in design and operation to a SPF. (two wires in a plug on the radiator) just remove and attach the two wires together or jump them (they are just a ground switch) If you have a single wire sensor in a hose or radiator, it is also just a ground. Just disconnect and use a jumper wire to a new ground to activate fans. Don't know if your fans will run with ignition off. SPF's will. Take one component out of the equation to get fans running. Another thing to verify is direction the fan or fans move the air. Air should be moving "into" engine compartment.
If you have original style Smiths gauges with a gas bulb temp sensor, and if the bulb sensor in mounted on the top of the intake manifold, when filling the cooling system and running the car (cap off) you can loosen the fitting for the bulb temp sensor on the manifold to let air escape. when the air escapes and antifreeze starts to seep out, tighten it back up. Front wheels elevated helps air to pool and escape. Even just a sloped driveway is enough angle. May take a few heating cooling cycles with cap off to remove all air in system. I note in photo you do not have a catch tank installed. Are you loosing antifreeze from small pressure relief hose when overheating? Both big hoses get hot right when you were having problems. When system is running correctly the new expansion tank should only have fluid in it up to the divider plate inside. Put you finger thru the radiator cap opening to feel the divider plate with large hole in it. The rest of the tank is for air and liquid expansion.
Hope this helps,
Blas

[jhv48]

You've still got air in the system. It took me several tries to finally rid my engine of all the air after I changed my thermostat.

The fact that your fans don't come on indicates that the coolant isn't as hot as your temp gauge shows. Your temp gauge sender is probably on the top of your intake manifold, where air tends to get trapped and can be very hard to remove.

Jack up the front end of the car. Buy one of these and use it until free of air. [ame="http://www.amazon.com/Lisle-24610-Spill-Free-Funnel/dp/B001A4EAV0"]Amazon.com: Lisle 24610 Spill-Free Funnel: Automotive@@AMEPARAM@@http://ecx.images-amazon.com/images/I/410gKy372TL.@@AMEPARAM@@410gKy372TL[/ame]

[Blas]

Take the thermostat out of the car and see if the problem persists. As was mentioned earlier, installing the thermostat backwards or if there is an interference with its opening due to its design, it could also be faulty. Taking it out removes it from problem statement.
Thermostat should say "Engine Side" on it and should have a weep hole in the plate body, which should be orientated in the top position when installed. Drill on 1/8" hole if it does not have one.
If this is an option for your engine: Get a "Balanced Thermostat" designed thermostat. I believe they fail open.
If your temp switch is similar in design and operation to a SPF. (two wires in a plug on the radiator) just remove and attach the two wires together or jump them (they are just a ground switch) If you have a single wire sensor in a hose or radiator, it is also just a ground. Just disconnect and use a jumper wire to a new ground to activate fans. Don't know if your fans will run with ignition off. SPF's will. Take one component out of the equation to get fans running. Another thing to verify is direction fan or fans move air. Air should be moving "into" engine compartment.