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Hi all,

My overflow tank had rusted out so I bought the pair of new tanks for Hall.

Just swapping them in now and I noticed that my current setup used the sensor fitting on the swirl tank to attach to a bleed hose that goes underneath and up to the radiator (not a stock radiator).

The new tank doesn't have the fitting as you can see so I'm about to revert to stock it seems. Am I in for purge hell ? My radiator has a bleed valve on it but I will have to block off the other fitting that went to my current tank.

thoughts ?



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Running a "bleed hose" from the tank to the radiator was a "Ford Technical Service Bulletin" suggestion.

I think it helps a lot. Some say it does nothing.

I would recommend that you make provisions to retain it.

Of course I also recommend the use of a pressure tester on the cooling system. I think that it expedites the pushing of the air out of the entire system.

On the Hall tank, that side fitting in a stock tank is only for the water temp sender, which Ford positioned there to give a lower temp reading. The sender rightfully belongs in the front of the block on the right top face, where it was for millions of other 351-C engines. Since nearly all US cars were so changed, Hall saw no value in adding a boss that would likely be plugged! Having the sender in the tank causes erroneous temp readings when the water level drops by only a little. Then you read the air temp over the water and get a false sense of confidence.... until it spits steam and coolant out the overflow!

The block is plugged with a pipe fitting which can be used in the stock tank while the sender screws into the block where the plug was. No parts needed; the sender wire connects to either position. Ford also had dealers put a resistor in that wire to further lower gauge temp readings. This nonsense went on until 1973 when Ford finally used a new 0-260F gauge in place of the 0-220F early gauge, which was often pegged in normal driving. There are other factory design screw-ups re cooling that are almost as easily fixed at home.

A rusted out tank(s) simply means that previous owners left old anti-freeze in far too long and the additives against rusting were used up. Bad cost savings decision!

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