Here's the parts and photos of what I have installed. It's on a 1970 Monte Carlo and it is a popular choice according to Monte Facebook groups. It is a 1975-1979 Nova overflow tank and it mounts nicely in the passenger side area and looks more stock vs the universal ones from the parts stores. It mounts with one bolt and rests on the inner fender.
The overflow tube runs into the tank and it has a vent towards the back side to allow it to have any excess flow out. I had a vented cap on it, but upon hard acceleration, it would spill coolant out. I put a non vented cap on it and figure the vent on the top of the tank itself should prevent any pressure issues in the tank. I added a fitting to the tank vent to allow a hose to route anything that may come out to flow under the car and not in the inner fender area.
One thing that got my mind pondering is the tube molded into the tank. It comes from the top and the coolant in the tank and the molded tube are level. This tells me there is air in the molded tube part and may suck that air into the system upon recovery. That air will get pushed out next time and if there is still an air pocket, will get drawn back in. Yes, ideally it wouldn't draw any air in, but it's less than an open overflow tube.In an ideal situation, would the molded tube have coolant all the way up or will it level with the amount in the overflow tank?
I have a small leak in the radiator and that may cause the levels to be the same and/or not drawing back in like it's supposed to. Spring it will get addressed as far as the radiator and repairs.
When I blew into the overflow tank overflow tube, I could see coolant going up the molded tube and into the radiator with the radiator cap off. I put the cap on the radiator and did it again. I could see some bubbles coming out from under the radiator cap. I know that's not scientific, but should it be allowed to blow into the radiator if the system is cold and been sitting for a few days? I would think if the system is leak free, it would not do anything because the coolant can't push the air pocket out of the radiator because it has nowhere to go. Bubbles tell me there is something not right.
I may be overthinking it, but when I don't completely understand something, my mind wonders.
The cap that is on it:
https://www.oreillyauto.com/detail/...let-monte-carlo?q=radiator+cap&pos=0The overflow tank:
https://www.classicindustries.com/product/all-years/chevrolet/nova/parts/551448.htmlNon vented cap for tank:
https://www.classicindustries.com/product/all-years/chevrolet/nova/parts/371978.htmlVented cap for tank:
https://www.oreillyauto.com/detail/...coolant-cap/mtm0/82590?q=82590&pos=0
