Guys and girls I have a problem with my radiator or something. When I top up the radiator with water and start the engine, once it warms up and the thermostate opens it releases water out the overflow pipe on the radiator and loses about 1.5 L of water every time??? Like a pressure build up or something. I have tried changing the radiator cap from 13 lb to a 20lb cap but still have the problem, it means every time I go out I need to top the radiator up so it doesn't over heat. I do have a new radiator as well.
Any idears??

Coombsy

 

Do you have an overflow tank? If not, you're only really supposed to fill the radiator to about 1" from the top of the tank. As the coolant heats up, it expands. It has to have somewhere to go, and if there isn't any extra space at the top of the radiator, it's going to go out the overflow tube. If you've got a coolant reservoir/recovery tank, you can go ahead and fill the radiator up all the way and the excess coolant that gets pushed into the tank will get sucked back into the radiator once everything cools down.

Does the car run hot? When it cools down, how low is the radiator on coolant? Does it still cover the tops of the cores?

 

Yep +1. You shouldn't have over heating problems if the radiator is low after it cools off, because after it warms up and the coolant expands, the radiator is actually full.

 

Hi thanks for the feed back.
Radiator will empty top tank and down to the cores, no I don't have a overflow tank may be that would help. Luckly the car doesn't run hot at all.

 

The coolant should just cover the top of the cores when you look inside from the cap, don't fill it up to the level of the cap- that's overfilled.

 

Mine does the same thing on really hot days.. I just had too much coolant in it..

 

Pick up one of those generic plastic overflow tanks from your local chain parts store. I've got one in my '67 and I like it well enough. That may help

 

Onboard here with the rest of the comments. Living in the era, we used to see water pukeing from radiators all the time. Don't over fill it and use a overflow tank. Make sure you burp your coolant system (warm up the engine until the t-stat opens with the cap off) to make sure you don't have air/steam expansion issues.

 

I picked up a nice little tubular stainless steel overflow tank from Big B Auto that I mounted to the right side of the radiator for about $50. It looks good and is compact and it doesn't interfere with anything else.

http://www.bigbauto.com

Unfortunately they don't seem to have any pics of their inventory, but something like that should solve your problem.

Hope this helps.

- Jason