47-55.1 hot 305 post radiator swap

[Mrs E7]

Good day all ..

Having a bit of an issue getting my head wrapped around a potential overheating issue...

I'm thinking I may have a bad new thermostat, or maybe should not have used the felt gasket and the rubber O ring gasket combined when replacing the thermostat, or my water pump is taking a siesta, or my temperature gauge just reads low.

Notes on what I have, and have done ...
Apologies for the length of the post, as I tend to include a little more than what I think might be the direct pieces/parts in the event things I think might be unrelated are actually related...

I'm fairly mechanically inclined, learn fast, but don't have a lot of exposure to engines other than my '62 Corvair Rampside, so I'm in a bit of a learning mode with a recent acquisition of a '49 3100... as such, I am stumped by what I thought would be an easy radiator swap ...
(famous last words.. I'm aware

Prior to purchase, the 305 in it actually was running very well .. albeit with signs of an exhaust leak .. cab floor is of Fred Flintstone nature, so it almost required a respirator... but I wasn't sure where the leak was coming from.
...temp gauge appeared to work, as did the radiator .. but of course 2 miles after $ exchanged, the gorilla glue the seller apparently used on the radiator broke loose ..

To get a running start at knowing what I am working with, I performed the following ...

- changed oil / filter
- changed fuel filter and hoses
- new fuel pump
- new fuel tank
- new fuel
- changed transmission fluid / filter
- flushed water jacket with distilled water .. old fluid drain and flush were surprisingly clean
- new radiator (from 2 core to 3 core Champion CC5100)
- new upper radiator hose - flexible steel
- new lower radiator hose - rubber
- 2 gallons of 50/50 Prestone *
- new water inlet housing (old one was crusty)
- new thermostat (180)
.. this came with both a rubber seal and a felt gasket. I used both after cleaning/scraping the intake surface thoroughly.
- checked/tightened/replaced as necessary all hose clamps/fittings I could get to

* I got a hair over 2 gallons of 50/50 in the radiator intending to get it to temp and top it off.

Engine started right up after fluid swaps.
Exhaust leak seemed reduced, no idea how, but there was no exhaust in the cab .. seemed to be from the passenger side pipe, behind the cab only now (haven't looked closely yet) ..
.. ran it a few minutes .. temp gauge got to about 140/150
- checked/topped trans fluid ....
- turned off and let it cool down for about 20 minutes ..
- checked oil
- radiator was still cool to the touch, but it had pressurized as evident by the nice fresh green spew as I removed the cap ..
... ran it a few more minutes..
... temp came up fast to 180, 190 .. got just shy of the 200 mark .. but I honestly don't know if the gauge is accurate .. needle raises from dead to just below the first mark of 100 with key in ACC ... which is the same amount of needle movement in the oil temp gauge.
... exhaust leak seemed to be worse and entering cab .. again, no idea how/why
- turned off
... radiator hot to touch .. upper hose hot .. forgot to check lower hose
... carefully/slowly removed the radiator cap with gloves and towel ... coolant was bubbling/steaming slightly.
... water pump very warm to touch, but I'm not sure how to know if this is working properly


My next step would be to make a mess with coolant and remove and test the thermostat, but I would love to hear from anyone with any thoughts on anything I missed or could/should do.



BONUS POINTS FOR INTEL
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I read something (quoted below) about the EFE valve that may be completely unrelated, but would appreciate any insight on this as well .. especially since I'm assuming the 'right' side engine components are the passenger side, and might imply this is not my issue.

--------------- EFE VALVE ----------
The purpose of this valve is to close when the engine is cold and re-route the exhaust gases from the right cylinder head back up through the head and through the bottom of the inlet manifold and out through the left hand head and left hand exhaust manifold.

When the water in the engine gets hot enough a TVS in the thermostat housing opens and directs engine vacuum to open the EFE valve and allow right side exhaust gas to flow out the right exhaust pipe.
--------------- // EFE VALVE ----------




Thanks in advance for any suggestions/ advice
- Wendy

PS:
I am very thankful for a place like this to post my garage drama .. if nothing else, it helped me recap in my mind that I believe I did everything properly, and just have a gremlin to catch.


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BUILD DETAILS TO DATE
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'49 Chevy 3100 Truck
- 305
... old headers (I originally incorrectly posted I had old iron manifolds)
- 700R4
- power steering
- front disk brakes / rear drums
- new Champion Cooling Systems CC5100 3 Row Aluminum Radiator
- new upper radiator hose - flexible steel
- new lower radiator hose - rubber
- new fuel pump
- new fuel filter
- new fuel tank
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