Is it bad to overfill engine coolent?

[Red Squirrel]

I have a slow leak in my engine coolant but it's not bad enough to fix (would cost a lot) so I just refill it every like, 6 months or so. Today I did it but I kinda went like an inch or two above the top most fill line. Is this bad, or can I get away with it? I know it's bad to overfill oil but that's because it will put too much stress on the moving parts, the coolent is just kinda sitting there and gets circulated, so I'm thinking it's not a big issue.

 

[Christobevii3]

No, there is a hose that allows it to flow out if its too high.

 

[IcePickFreak]

^
What he said. Just don't be too concerned if you see a little anti-freeze under your car.

 

[Red Squirrel]

I don't think mine has a hose but maybe I did not see it. But it's sitting in a "basin" kinda like the windchill washer. But good to know it's not that bad.

 

[jlee]

I don't think mine has a hose but maybe I did not see it. But it's sitting in a "basin" kinda like the windchill washer. But good to know it's not that bad.

At the top of the coolant reservoir, there's likely a dump tube that'll spit coolant out if it's too full.

Where's the leak? My car was leaking last year - turned out to be a worn-out clamp. Very easy fix.

 

[brblx]

there will be an overflow spout somewhere if the reservoir is just hooked to a hose at the radiator neck. if for some reason there's not, it would just pop the plastic cap off, which is not designed to hold pressure.

if the overflow tank is in circulation with the cooling system (two hoses going to it, cap is screw on with a pressure rating), it's probably sealed. it may not burp air properly if it's filled to the top, but otherwise i doubt there would be a problem from putting a little extra in it.

 

[herm0016]

you should check your actual radiator coolant level also, much of the time filling the overflow will not actually fill the radiator with coolant. just take the cap off when the car is cold to check it, it should be full to the top.

 

[LTC8K6]

A lot of cars have no cap on the radiator and the overflow tank is pressurised.

 

[exdeath]

If there isn't an overflow tank, you have what is called a degas bottle in a sealed system that should only be filled to the max line to allow for coolant expansion and air removal. If it's overfilled it will just ooze out the pressure cap for a while when it gets hot.

 

[Woodzer79]

One thing as far as antifreeze is concerned is make sure if you see it under your car from a leak or whatever make sure you clean it up. DO NOT leave it on your drive way or anywhere for that matter because AF has a sweet taste to it and pets will lick it up of they come across it and it doesn't take much to kill a dog or cat. So just be warned CLEAN UP AFTER YOUR SELF.

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[LTC8K6]

One thing as far as antifreeze is concerned is make sure if you see it under your car from a leak or whatever make sure you clean it up. DO NOT leave it on your drive way or anywhere for that matter because AF has a sweet taste to it and pets will lick it up of they come across it and it doesn't take much to kill a dog or cat. So just be warned CLEAN UP AFTER YOUR SELF.

Necro much?

Well, if your dog isn't wandering around loose...

 

[sontakke]

"windchill" washer?

 

[razel]

please delete