Rad.Cap

[not2old]

Tired of Seeing cooland under the car after driving , so I put a gallon antfreeze jug in front of rad. to coolect from overflow hose. Anyone know what year cap we can use to get to recycle back from overflow. There is no listing for recycle cap for our years.

Alan L

 

[OLE PONY]

The overflow tank kit was available as an accessory in 1973. Not sure waht the cap part number is.

 

[Wolverine]

There is no difference between a cap used with an overflow or without an overflow...

1. The overflow tank kit and especially the radiator cap was alway a piece of crap.

2. The official "fill" level of the radiator is 1" below the radiator cap. If you always fill the radiator, you will always lose 1" of water. Doesn't quite make sense to me, just a fact I have lived with since 1973.

3. If you want to keep your radiator filled to the top with water, then get an overflow tank. The 1" of overfill will be put into the tank when your motor gets warmed up, and it will put it back in when it gets cooled down. Never put too much thought into it. Because you are exercising the radiator cap, it will wear out the radiator cap spring. This causes the cap to open at a lower pressure, which will result in the radiator puking sooner than it should. A 14 pound cap should allow the water temp to get to 250 degrees before boiling over. If you are boiling over below 250, replace your cap.

If you are still having issues, check this out:

http://www.cougarpartscatalog.com/waterrestrictplate.html

http://forums.vintage-mustang.com/vintage-mustang-forum/623722-70-351c-pushes-water-out-radiator.html

I haven't had a cleveland motor in 30 years, so I forgot about this baby until my current rebuild project. Probably THE most important single item regarding the 351C that everyone forgets about.

 

[Tnfastbk]

Tired of Seeing cooland under the car after driving , so I put a gallon antfreeze jug in front of rad. to coolect from overflow hose. Anyone know what year cap we can use to get to recycle back from overflow. There is no listing for recycle cap for our years.

Alan L

Here is what I put on mine, just in case

 

[Wolverine]

Here is what I put on mine, just in case

Mine is a little more utilitarian...

 

[not2old]

Looked at the cleveland t-stat restictor and I'm currious how the coolant flows from the block if the opening is covered. Looks like it would cause overheating by blocking

Alan L

 

[Don C]

It actually works the other way. Most engines have a little rubber hose that runs from the water pump to the block. The purpose of this is so that when the thermostat is closed the water pump can still circulate some coolant around in the block, and to keep the water pump from cavitating. In the Cleveland engines the bypass plate performs the same function, providing a path for some coolant to circulate when the thermostat is closed. When the thermostat opens the bypass is closed, which forces all of the coolant to circulate through the radiator. If the bypass remains open, as when a wrong thermostat is used or the restrictor plate is missing some of the coolant just keeps circulating around the block, through the pump and right back into the block, and is never cooled through the radiator. Hope this sketch helps, sorry for the quality, is the best one I have.

 

[73vertproject]

That's a nice explanation, Don, and the sketch is just fine. Explains how the opening and closing of the thermostat controls cooling of the coolant.

 

[Tnfastbk]

Here is a pic of a new one

 

[not2old]

Here is a pic of a new one

This must be my concern. engine temp stays 195 but hear coolant boiling at bypass/waterpump area on hot shutdown for about 2-4minutes

Ordered one today. Thumping too much to not make the change.

Alan L