Why would I start another overheating thread

[dacfan]

Finally got my '74 rolling. Just short little runs around the neighborhood right now. I had to remove the rad to solder a side back on. After flushing the block and radiator I thought I got all the air burped out, but she's overheating after sitting idle for five minutes or so. Fan switch is bad, so it's not coming on but I've got a single throw toggle on it. Even with the fan on, the gauge goes 3/4 up. I always cut it off before it reaches red. I'm still worried I'm doing damage with it running so hot. All of radiator is hot. Top and bottom hoses are hot, Here's what's weird. I've got a top rad hose going into block and a bottom hose coming out of water pump into rad bottom. There is no tee and thermostat on bottom hose. Somebody pulled all of that off and ran it straight. Is this what is causing my overheat? Do I need a tee, housing, and three way tstat?

[So Cal Mark]

usually they put a stat in the head when they remove the external stat. Can you see water circulating in the radiator?

[dacfan]

It looks like I've got movement in the radiator. I know I've got movement in the "T" between the back of block and heater. I took the cap off and started the engine just to make sure the water pump was ok. Coolant shot four feet in the air. That would lead me to believe the stat is either working or stuck open? I may still have an air pocket, but I don't see how. I don't see any evidence of head gasket issues or anything else that would cause overheating. Maybe I need to drain it all and start over.

[BEEK]

74 spiders came with a standard thermostat in the head, no 3 way junction. i would check the thermostat itself first, i would also have the radiator flushed/rodded. ect. if the thermostat proves to be ok.i would replace it anyway for the few $$ it costs. 180 degree. only 1 time have i seen the impellers actualy worn /rusted off a waterpump. at least use a garden hose and back flush the radiator. the original 74 radiators, you could not see the core thru the neck, , you might remove the fan unit and use a flashlight an try and see the condition of the core, if the tubes are restricted. just a thought

[dacfan]

Beek, thanks to you and Mark for the advice. I had to solder the right side back onto the radiator when I got the car. I noticed when I got it off the trailer that the fan housing was above the radiator. When I puuled the rad, the right side of it came off. I flushed it several times and visually inspected it for any leaks or core problems. It really looks to be in much better shape than I expected. I soldered the side back on and remounted the fan housing. I did not do a pressure test, but I've seen no leaks since I reinstalled it. While it was off, I replaced the timing belt as the one on it was looking bad and had a fiat logo on the belt, leading me to believe it was o-l-d. I flushed the engine from back of block at the heater tee and from both the top and bottom hoses. Overall, both the rad and block were running much cleaner water than I expected. Knowing that the stat in the head is factory and the '74 didn't have the tee setup answers some questions. I''m not even going to boil the stat. I''ll just replace it and if I continue to have problems, I'll start begging for help again. I do have even heat all over the rad and both hoses are warm, so I don't think I have any obstructions. Thanks for the help and I'll let you guys know how it turns out. ONE MORE QUESTION: I've let the temp gauge run almost to red mark but not into the red, pulling over and shutting down just in time. Is it likely that I've done any damage to the head or gasket? Warped heads is not something I want to see.