My FD3S overflows antifreeze when parked hot after being driven
#1
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My FD3S overflows antifreeze when parked hot after being driven
I drove my 93 FD3S for five miles today, when I parked it in my garage the antifreeze overflowed from the overflow tank all over the garage floor. I checked for a damaged to the tank and the fill spout to no avail. This has happend several times now but it does not overflow every time. Does anyone have a solution to this problem?
#4
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Wow...Not necessarily. It is more than likely the result of an overfilled coolant system. As the Coolant heats and expands it overflows the overflow tank which isn't sealed. It can also happen as a result of a poor seal on a Coolant Cap, either at the filler neck or the AST. I have had this happen many times. Let the car get completly cooled then pull the dipstick out of the coolant resivoir and check for proper level. If it has too much in it, get a small piece of tubing and syphon it out through the dipstick hole.
Here's a link to the Big Fat Cooling thread...a must read for all FD owners...
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/big-fat-fd3s-cooling-thread-571088/
Here's a link to the Big Fat Cooling thread...a must read for all FD owners...
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/big-fat-fd3s-cooling-thread-571088/
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Wow...Not necessarily. It is more than likely the result of an overfilled coolant system. As the Coolant heats and expands it overflows the overflow tank which isn't sealed. It can also happen as a result of a poor seal on a Coolant Cap, either at the filler neck or the AST. I have had this happen many times. Let the car get completly cooled then pull the dipstick out of the coolant resivoir and check for proper level. If it has too much in it, get a small piece of tubing and syphon it out through the dipstick hole.
Here's a link to the Big Fat Cooling thread...a must read for all FD owners...
https://www.rx7club.com/showthread.php?t=571088
Here's a link to the Big Fat Cooling thread...a must read for all FD owners...
https://www.rx7club.com/showthread.php?t=571088
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Hopefully it is just a bad coolant cap for you but my car exhibited these symptoms when a coolant seal was failing. Exhaust gases would make their way into the cooling system and overpressure the system and push coolant into the overflow tank. A sign of this happening is black goo on the overflow tank dipstick. When the car cooled off the exhaust gases in the cooling system would prevent it from pulling coolant back from the overflow tank. The net result of that problem was a coolant tank that overflowed more often than not after the car was parked. If a new coolant cap doesn't fix the problem then definitely do the champagne test.
#17
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i had this happen to me a couple of weeks ago.it dumps the coolant to the reservoir because it cannot hold pressure.I bet it only overflows when you try to add more coolant because your thinking that it must be low from leaking all that coolant.. turned out to be the ast cap not sealing right..
#18
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i had this happen to me a couple of weeks ago.it dumps the coolant to the reservoir because it cannot hold pressure.I bet it only overflows when you try to add more coolant because your thinking that it must be low from leaking all that coolant.. turned out to be the ast cap not sealing right..
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There's a good thread somewhere that explains the way the FD cooling system works. Basically in a nut shell the coolant expands as it gets hot hence it goes into the overflow bottle. Normally when the car cools down it will draw or suck the coolant from the overflow back into the system only if the system is tight and sealed - which is why you need proper radiator and AST caps.
If you open your filler cap you will see the coolant sitting there. Under normal circumstances if you then open your AST cap your coolant will start to slowly go down - where does it go? Into your overflow bottle. If you put the AST cap back on it 'should' stop going down.
So you can see where I'm getting at. If you open your filler cap and your AST cap is on but coolant level is still going down, then most likely its your AST cap but just to be sure replace both of them while your at it.
I replaced my AST too at this point as well as the hoses to it and problem solved. Just remember how old they are now.
If you open your filler cap you will see the coolant sitting there. Under normal circumstances if you then open your AST cap your coolant will start to slowly go down - where does it go? Into your overflow bottle. If you put the AST cap back on it 'should' stop going down.
So you can see where I'm getting at. If you open your filler cap and your AST cap is on but coolant level is still going down, then most likely its your AST cap but just to be sure replace both of them while your at it.
I replaced my AST too at this point as well as the hoses to it and problem solved. Just remember how old they are now.
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There's a good thread somewhere that explains the way the FD cooling system works. Basically in a nut shell the coolant expands as it gets hot hence it goes into the overflow bottle. Normally when the car cools down it will draw or suck the coolant from the overflow back into the system only if the system is tight and sealed - which is why you need proper radiator and AST caps.
If you open your filler cap you will see the coolant sitting there. Under normal circumstances if you then open your AST cap your coolant will start to slowly go down - where does it go? Into your overflow bottle. If you put the AST cap back on it 'should' stop going down.
So you can see where I'm getting at. If you open your filler cap and your AST cap is on but coolant level is still going down, then most likely its your AST cap but just to be sure replace both of them while your at it.
I replaced my AST too at this point as well as the hoses to it and problem solved. Just remember how old they are now.
If you open your filler cap you will see the coolant sitting there. Under normal circumstances if you then open your AST cap your coolant will start to slowly go down - where does it go? Into your overflow bottle. If you put the AST cap back on it 'should' stop going down.
So you can see where I'm getting at. If you open your filler cap and your AST cap is on but coolant level is still going down, then most likely its your AST cap but just to be sure replace both of them while your at it.
I replaced my AST too at this point as well as the hoses to it and problem solved. Just remember how old they are now.
Here's "The Big Fat FD3S Cooling Thread"
https://www.rx7club.com/showthread.php?t=571088
The best I've read on this issue!!
#23
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it can also happen if the stock coolant overflow line is pinched off or deteriorated, so that coolant overflows but is not sucked back into the system...that was my problem a few years ago
#24
To be on topic....I just bought my FD and its leaking coolant. The previous owner replaced the overflow tank. My friend and I checked out the car yesterday and the previous owner put in way too much coolant because he said it was leaking out. Okay so we do the pressure test on the radiator and there are no leaks, we suck out some coolant so its on the full line ( not over full ) and as I was driving...it beeped like mad crazy telling me to add coolant but its already full. So replacing a thermostat and radiator/ ast cap will solve my problem? I added coolant but it doesnt seem to be sucking into the engine. Im talking about the little resevoir on the right. Please help me guys and sorry for being a noob......