Flushing Cooling System

Maintenance advice to keep your Spider in shape.
18Fiatsandcounting
Posts: 3798
Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Flushing Cooling System

Post by 18Fiatsandcounting »

bdinardo wrote:Upon filling up the radiator, I could only fill it up about 3/4 of a gallon. I squeezed all of the hoses but couldn't really get much more than 3/4 of a gallon. Is this normal and should I just start the motor and let it cycle or do I need to do something different to get more in before starting the car? I'll likely buy and install a "Tee" piece for the back of the head heater hose to fill there as well. Thanks.
Did you drain the block? The radiator itself holds about a little less than a gallon while the rest of the system (block, hoses, heater core) holds another gallon or so. A "T" connector on the heater hose is the best way to resolve all this and it's what many of us end up installing.

I typically fill the radiator until I can see coolant in the bottom of the neck, then start the engine with the radiator cap still off, and then slowly dribble in more coolant as the level drops as the coolant circulates. Keep an eye on the temperature gauge for anything amiss. I can only do this for about a minute or so until the engine starts to warm up enough so that coolant starts coming up the radiator neck again, at which point I quickly shut down the engine and seal the radiator cap. Then warm up to operating temperature and check for leaks.

Remember to keep your overflow reservoir about 1/2 to 2/3 full.

-Bryan
bdinardo
Posts: 43
Joined: Mon Aug 09, 2021 12:32 pm
Your car is a: 1979 Fiat 2000

Re: Flushing Cooling System

Post by bdinardo »

[/quote]
Did you drain the block? The radiator itself holds about a little less than a gallon while the rest of the system (block, hoses, heater core) holds another gallon or so. A "T" connector on the heater hose is the best way to resolve all this and it's what many of us end up installing.

I typically fill the radiator until I can see coolant in the bottom of the neck, then start the engine with the radiator cap still off, and then slowly dribble in more coolant as the level drops as the coolant circulates. Keep an eye on the temperature gauge for anything amiss. I can only do this for about a minute or so until the engine starts to warm up enough so that coolant starts coming up the radiator neck again, at which point I quickly shut down the engine and seal the radiator cap. Then warm up to operating temperature and check for leaks.

Remember to keep your overflow reservoir about 1/2 to 2/3 full.

-Bryan[/quote]

Thanks Bryan. I did indeed drain the block on the passenger side which is why I was perplexed as to the small amount allowed in. I did not fill the reservoir and didn't get the car started enough (hot enough) to start circulating, as I ran into other issues. I'll follow your suggestions though and install the "Tee" in the heater hose, fill that up through there, fill up the reservoir a bit, fill the radiator and then get the engine fired up and add throughout that process. Much appreciated.
TX82FIAT
Posts: 1814
Joined: Mon May 03, 2010 11:04 am
Your car is a: 82 Fiat Spider 2000 CSO
Location: San Antonio

Re: Flushing Cooling System

Post by TX82FIAT »

Your Thermostat junction with three large hoses on the passenger side is closed since the car is cold. The T fitting at the top of the hose that leads into the firewall for the heater will allow you to fill those areas currently filled with air. Some people will drill a hole in the thermostat to allows coolant to pass through as well as trapped air to process up.
Buon giro a tutti! - enjoy the ride!

82 Fiat Spider 2000
03 BMW M3
07 Chevy Suburban
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