1957 pushes coolant past the cap

[Moms 57 Bird]

I replaced the water pump with a high volume pump, new thermostat, new hoses and rotted out the original radiator. Put on a new 13psi cap and coolant pushes past the cap and all over the radiator and inner hood once I slow down (traffic or pulling into the driveway). It stays cool on the (mid way in the normal range) and then when I slow down or pull into my driveway it pushes to the upper limit of the normal range and blows past the cap. It doesn't even leak down the overflow tube. Thoughts? Thanks.

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[lcboyer]

If you don’t have a fan shroud. It. Might help

 

[Rod Bender]

The 57 Bird is a hot running car in more ways than one. They didn’t have trouble in the other cars and trucks but the 55, 56, 57 did. The water pump on those cars had the back plate that the water would hit a 90 degree resistance before leaving it. There’s a guy here in Arizona that designed an angled exit for the liquid that did seem to help for a couple hundred dollars. You should be able to find it through a search engine. One of my original fan blades of 4, almost went though my hood, so I replaced that with a 6 blade. I try my best to keep the car at about 94% original, but am able now to keep the temperature down to just barely opening of the thermostat! It’s a game that takes a while to conquer! Attached is a picture of the old baffle that I replaced with an angled one. The pen is pointing to the 90% “block”!

 

[Moms 57 Bird]

If you don’t have a fan shroud. It. Might help

Thanks. I have a stock fan shroud and stock fan.

 

[Tom Alpers]

Any chance the thermostat is in backwards? If it's heating up that fast, sounds like it only takes a minute or two to go from midscale to boil over, something more is wrong than the usual marginal cooling issues. If you're not getting water out the overflow tube but it's really just shoving past the cap and coming out the top of the neck past the cap seal I would suspect a bad cap or the wrong cap.

 

[doug7740]

I replaced the water pump with a high volume pump, new thermostat, new hoses and rotted out the original radiator. Put on a new 13psi cap and coolant pushes past the cap and all over the radiator and inner hood once I slow down (traffic or pulling into the driveway). It stays cool on the (mid way in the normal range) and then when I slow down or pull into my driveway it pushes to the upper limit of the normal range and blows past the cap. It doesn't even leak down the overflow tube. Thoughts? Thanks.

A major contributor to overheating conditions can be caused by neglecting the cooling system. It is recommended that the cooling system be drained and flushed every two years. Proper cooling system maintenance prevents rust and sludge buildup around the cylinder wall cooling jackets. The attached photos show what can happen when a cooling system is not properly maintained.





Removal can be accomplished by removing as much rust as possible by digging and probing with a coat hanger or similar object. Pressure wash until all the rust is flushed from the block allowing coolant to flow freely around the external cylinder walls inside the engine block. Replacing the core plugs with brass plugs.

When servicing the cooling system use a 50/50 mix of anti-freeze/coolant and water. Coolant rust inhibitors start to break down in a couple of years requiring the system to be drained and the coolant replaced. A clean cooling system promotes a cool running engine.

doug7740
1955 Thunderbird Blue