2013 Subaru Legacy random glycol dump

I have a 2013 Subaru Legacy 2.5i Limited with 104k miles that I make sure to keep up with maintenance with due to it being my daily driver.

 

The other day we had a huge 2 day snowstorm in NH, so like usual I warm up the car, dust it off, and move it into the street so I can snowplow the driveway. When I moved it back I noticed a large quantity of coolant in the snow. When I checked the reservoir it was down below the "low" line, about an inch left in the tank.

 

Put it up on the lift later that day, couldn't find any drips, breaks, all visual hoses weren't dry rotted or cracked, all seals were dry and clean. Let it run in the driveway for 20 minutes. Nothing. So I topped off the coolant back to normal level. The next day, the same thing happens - start it up, drips all over the snow (less this time, the reservoir only went down about a half inch from "full" line). So I let it cool off thinking that cold start is causing it from quick pressure to cold cracked hose. Still couldn't recreate the leak.

 

Today I dropped it off at my mechanic's. Comes back inconclusive. Told me they did a visual, didn't see anything, then pumped the coolant system up to 16lbs pressure and let it sit, held no problem. He told me to just keep an eye on it but the fact that I lost about 8oz of coolant scares me. Could have been over time, but I checked coolant level on the last oil change about 2 months ago and it was at the normal level.

 

Anybody else have this problem or know what could have possibly happened? Any reason why the system would just decide to dump/overflow? Due to cold weather, snow, or any other known issues? Appreciate it.

If I had to guess, it sounds like your overflow reservoir is cracked. I'd try filling it a little higher than normal and get a look at it the next time you start it. Maybe even put a few drops of food coloring in it to see if its coming from the reservoir or the rest of the system.

Did they pressure test your cap as well?

 

Sent from my SM-G965U using Tapatalk

If I had to guess, it sounds like your overflow reservoir is cracked. I'd try filling it a little higher than normal and get a look at it the next time you start it. Maybe even put a few drops of food coloring in it to see if its coming from the reservoir or the rest of the system.

 

This would be the first thing I would look at. All that pressure could cause the leak to seam through a crack.

Did they pressure test your cap as well?

 

Sent from my SM-G965U using Tapatalk

 

The cap could be replaced for cheap, and maybe fix the issue as long as there's no cracks...

Thanks for the replies, but I don't think it is coming from the cap or reservoir. I checked all around the engine bay immediately after I saw the drips on the driveway and saw that everything was dry. Would have been fairly easy to see it coming from either of those, along with the snow that had been scraped up in the belly pan.

 

The other thing that is boggling me is how it got all the way to the center-rear end of my car. If it were the cap or reservoir cap, it would have most likely dripped straight down under the engine. The drips I found on the driveway were located in the center, towards the rear seat of the car. Possibly dripping on belly pan plastic and pouring out when I move the car? But the times I found the drips on the driveway, I moved the car in reverse, so it could only fall closer to the front of the car.

Are you sure that wasn't brake fluid?

Are you sure that wasn't brake fluid?

 

Yah, what color was the fluid? Maybe it could be coming from a line or something

Definitely not brake fluid. Color was lime green in the snow. My coolant tank was also down to about an inch left in it, all adds up to being coolant to me.

 

Just dropped about an inch yesterday when I went out to check it before I started it. But no drops or sign of leakage underneath where I parked or in the engine bay at a quick glance before I left. But then held tight after a 3 hour drive to ski mountain and back. Checked this morning and held tight.

My brake fluid reservoir is also filled to correct amount, so hasn't leaked since I have never had to top it off.

If it has the OEM coolant in it, it would be blue, not green.

If the cap leaked for some reason I had a stant cap do that on my gt, it could have overflowed the overflow tank. It could also be the weep hole on the water pump, my pump was dumping lots of coolant in the summer from there, eventually like a quart per trip. I don't know what year subaru switched to timing chains but if you have a belt still when you do the belt, do the water pump too, the thermostat, and front oil seal. And don't reuse the water pump bolts... they may snap when you torque them.