Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 06-04-2020, 09:53 PM   #1
foxonwheels
Scooby Newbie
 
Member#: 329372
Join Date: Aug 2012
Location: Philadelphia, PA Suburbs
Vehicle:
2013 WRX Hatch
SWP

Question Overflowing coolant reservoir expansion tank

2013 WRX, 108k, Cobb stage 1

For the past few months, I've noticed my coolant expansion tank has been overflowing. I've done the burp procedure with a spill free funnel at the turbo tank a few times now. With all air out of the system, I did not experience any issues after taking a few short drives and staying out of boost. But boosting or going on a 40 min drive to and then from work caused the expansion tank level to be noticeably higher than where it started even after the engine cooled overnight.

Whenever it happens, there is obvious air in the upper rad hose when squeezing it once the engine cools down. Upper turbo coolant tank is also low. I have since replaced both the turbo tank and radiator caps with new OEM replacements. They are not reversed. My lines at the rad are connected properly. Both upper and lower rad hoses are hot when the engine is warm.

I did the timing belt, water pump, and t-stat (all OEM) a few months ago and replaced the coolant. There were some small rubber crumbs in the coolant and my upper/lower rad hoses felt a bit crunchy, so I replaced with silicone. Fans come on right at 205 and shut off around 192, new t-stat appears to be working fine.

I bought a pressure test kit and hooked up at the rad. Pumping up to around 13PSI and it holds, although drops maybe 1 PSI after 10 minutes. I also tested at the turbo tank and went up to 15PSI, again it very very slowly dropped to 13-14PSI. No obvious sprays, drips, or leaks that I could see.

No bubbles or foam in the expansion tank when revving. No signs whatsoever of milky coolant. My coolant tank does look a bit dirty inside near the top few inches where there normally is no coolant.

Tonight I reburped again and noticed something interesting. With the spill free funnel in the turbo tank with a decent amount of coolant in the funnel, I restarted the engine and revved a few times. No bubbles or excessive rise in the funnel. I then plugged the funnel, capped the turbo tank, and put the funnel on the radiator and removed the funnel plug. Revving now caused the coolant level in the funnel to immediately rise dramatically and stay there. Is this expected behavior or does it help diagnose?

With the funnel back in the upper tank, I notice that when I squeeze the upper rad hose a few times in succession, I can hear a water blooping noise somewhere under the intake manifold to the right of the turbo/upper coolant tank. Sounds like when a sink or a tub drains at the very end and you get a few 'glugs'. I'm guessing an air bubble is stuck and didn't work its way out. Does this mean anything?

Just trying to see if there is anything else I can try before I convince myself its a head gasket, which I was quoted at $3100 and will likely spell the end of my time with this car. I've done the burping procedure about 5 times by now over the past few months. Would a pinhole leak or bad hose clamp be able to cause such a dramatic rise in coolant in the expansion tank without showing signs of a leak? Clogged line or blocked passage somewhere? Do I bypass the TB coolant run? Replace the radiator? Don't want to throw more money at it if it certainly sounds like HG.

Last edited by foxonwheels; 06-04-2020 at 10:00 PM. Reason: what about a blockage
foxonwheels is offline   Reply With Quote
Old 06-05-2020, 05:22 AM   #2
mooshon
Scooby Newbie
 
Member#: 431456
Join Date: Oct 2015
Default

I can tell just try this manual and make CO test.
https://strongforsubaru.com/resource...lant-bleeding/
mooshon is offline   Reply With Quote
Old 06-05-2020, 10:11 AM   #3
Jedi03
Scooby Specialist
 
Member#: 491095
Join Date: Sep 2018
Chapter/Region: SWIC
Location: New Mexico
Vehicle:
2009 STi Blue
Blue

Default

if you are bleeding it in full w/spill free i personally keep it in until the water starts to steam, i will often let it cool overnight if i have the time then plug and cap it...to make sure caps are not reversed you have the circle one on the radiator and the one on the upper reservoir is the oval one? if its backwards wont hold pressure properly at the radiator...also bleed it with heater running and after at operating temp give it a few revs, not to high but ~3k, i often will also hold it there to simulate a normal drive then let it idle down
Jedi03 is offline   Reply With Quote
Old 06-06-2020, 09:17 AM   #4
Jay11STI
Scooby Newbie
 
Member#: 492422
Join Date: Oct 2018
Chapter/Region: Tri-State
Location: North Jersey
Vehicle:
2011 STI

Default

I would try doing what Jedi03 has suggested first. I wouldnt want to condemn the headgaskets either until everything possible has been done.

Have you noticed any abnormal coolant consumption or loss? When you say "coolant overflow" are you saying that its litterally pouring out as in excessivly overflowing and spilling from the tank?

I only ask because in your first paragraph you said "I did not experience any issues after taking a few short drives and staying out of boost. But boosting or going on a 40 min drive to and then from work caused the expansion tank level to be noticeably higher than where it started even after the engine cooled overnight."

Coolant level will rise in the tank as it gets hotter due to thermal expansion so its not going to be at the same level in the tank after its hot compared to the level it was when the engine was cold after siting overnight.
Jay11STI is offline   Reply With Quote
Old 06-06-2020, 10:46 AM   #5
Samurai Jack
Scooby Guru
 
Member#: 21145
Join Date: Jul 2002
Chapter/Region: NESIC
Location: Not in my own time
Vehicle:
2002 Enemy of Aku

Default

Sounds like you have been checking just about everything but also sounds like you still have air in the system. Could be from small leaks or could be you just never got all the air out of it.

Have you checked / re-checked all coolant / heater hose connections? Hoses compress over time under the clamps so definitely a good thing to check.

I have never used the funnel method you used to fill the cooling system. Many people have come to the forums with an issue similar to yours, have used the funnel method and have found air still in the system.

Suggest you try this method, which is how I always do it and never encounter your issues:
- motor off & cooled
- fill coolant overflow bottle to the fill cold line
- fill radiator allowing time for coolant to work it's way through the system pushing air out.
- cap radiator
- fill turbo expansion tank same as radiator
- start engine and let it idle. no revving needed. this works coolant throughout the system pushing air towards & out of the turbo expansion tank.
- fill expansion tank as needed
- after about 10 minutes, you can cap the expansion tank & check level of overflow bottle
- drive around for ~ 10 minutes & check overflow bottle. fill as necessary.

Never had an issue this method. I have never burped nor ever had a need to burp the system.

Now, since everything is already filled, I would suggest starting with a cold engine and remove the turbo expansion tank cap.

How low is the fluid level?
Start from here.
Samurai Jack is offline   Reply With Quote
Old 01-11-2021, 11:28 PM   #6
2ball
Scooby Newbie
 
Member#: 464330
Join Date: Mar 2017
Default

was you overflowing issue a head gasket? If so how did you finally diagnose it?
2ball is offline   Reply With Quote
Old 01-12-2021, 02:45 AM   #7
spoolinsti05
Scooby Guru
 
Member#: 108051
Join Date: Feb 2006
Chapter/Region: AKIC
Location: Oneonta, NY
Vehicle:
2005 WRX STi
WRB

Default

Make sure you have your funnel on the resivour not the radiator. And make sure your cap is not leaking. Coolant pressure sensors help a lot all cars should have them. Find that leak though that doesn't help any.
spoolinsti05 is offline   Reply With Quote
Old 01-12-2021, 06:51 AM   #8
rtv900
Scooby Guru
 
Member#: 428511
Join Date: Aug 2015
Location: philadelphia
Vehicle:
2016 STI

Default

Quote:
Originally Posted by spoolinsti05 View Post
Coolant pressure sensors help a lot all cars should have them.
smh..
rtv900 is offline   Reply With Quote
Old 01-15-2021, 12:13 AM   #9
spoolinsti05
Scooby Guru
 
Member#: 108051
Join Date: Feb 2006
Chapter/Region: AKIC
Location: Oneonta, NY
Vehicle:
2005 WRX STi
WRB

Default

Quote:
Originally Posted by rtv900 View Post
smh..
Yea sometimes I shake my own hand..
spoolinsti05 is offline   Reply With Quote
Old 01-12-2021, 10:33 AM   #10
Jedi03
Scooby Specialist
 
Member#: 491095
Join Date: Sep 2018
Chapter/Region: SWIC
Location: New Mexico
Vehicle:
2009 STi Blue
Blue

Default

don't know why i didn't put this in my last post, but have noticed Subaru's have a problem bleeding the air out of the heater core...i have pulled one hose while the vehicle is running to help get it out too...happened on 92 legacy 2.2 and a 99 impreza 2.0...not sure why, didn't have issues any time doing it on my STI but not to say it couldn't happen. I recommend do it while engine is cooler, i did it while hot, i do have a good pain tolerance but don't recommend doing this to anyone...220 degree or hotter coolant is no Bueno...
Jedi03 is offline   Reply With Quote
Old 01-12-2021, 10:54 AM   #11
Max Capacity
Scooby Specialist
 
Member#: 149347
Join Date: May 2007
Chapter/Region: NESIC
Location: Tolland, CT
Vehicle:
05 LGT ,09 SpecB
Black/silver

Default

Quote:
Originally Posted by Jedi03 View Post
don't know why i didn't put this in my last post, but have noticed Subaru's have a problem bleeding the air out of the heater core...i have pulled one hose while the vehicle is running to help get it out too...happened on 92 legacy 2.2 and a 99 impreza 2.0...not sure why, didn't have issues any time doing it on my STI but not to say it couldn't happen. I recommend do it while engine is cooler, i did it while hot, i do have a good pain tolerance but don't recommend doing this to anyone...220 degree or hotter coolant is no Bueno...
May be jacking up the right front corner of the car as high as you can get it and turning on the heater to full heat while the engine is running, while your burping the system will help.

I do that.
Max Capacity is offline   Reply With Quote
Old 01-15-2021, 12:12 AM   #12
spoolinsti05
Scooby Guru
 
Member#: 108051
Join Date: Feb 2006
Chapter/Region: AKIC
Location: Oneonta, NY
Vehicle:
2005 WRX STi
WRB

Default

Quote:
Originally Posted by Max Capacity View Post
May be jacking up the right front corner of the car as high as you can get it and turning on the heater to full heat while the engine is running, while your burping the system will help.

I do that.

Thats what they recommend doing with the Nissan 240.

I drill a 1/8 hole in the thermostat.. Helps a lot!

Can even get those bleed valves for heater hose like on the jeeps Napa sells them..

Also you can get this a coolant vacuum refill kit theyre cheap and work great making it quick and easy to get the air out.
spoolinsti05 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 08:37 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.