Welcome to the North American Subaru Impreza Owners Club Thursday July 20, 2017
Home Forums 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.
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 06-13-2017, 11:01 PM   #1
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Exclamation Coolant Overflow Mystery! But It's Not The Head Gasket?

Okay so here is the problem:
- When driving hard and under heavy boost such as at autocross or at the track, coolant pushes into the overflow tank to the point where it sprays out of the top and into the engine bay.

Here are details about my WRX:
- 2014 WRX Premium Sedan
- 41k Miles on odometer
- 325whp/385wtq on E75 @ 20 PSI
- Tuned to above levels since 02/2017

Here are the modifications:
- Full Catted TBE
- Cobb Intake
- Cobb Flex Fuel Kit
- Cobb FMIC
- 1000cc ID Injectors
- AEM 320lph Pump
- IAG AOS
- Koyo Aluminum Radiator

I'll just jump to when the problem first started...
I DIY installed the flex fuel, fmic, and pump from the list above and then got tuned shortly after by Calvin of Dotson Tuning on AWDTunings Dyno. The car did really well and put down 325whp no problem.

The following weekend, I take my car to autocross and start doing runs. After the first session I popped the hood and noticed coolant in the engine bay that had clearly come from a full to the brim overflow tank that was bubbling. No signs of oil, it just looke like clean coolant with big air bubbles. I dismissed it at the time and ran the rest of the day with no overheating. I even drove back on the highway for an hour.

So fast forward a month later with coolant issues but some gaskets in the fuel pump came loose and i had to fix it and get retuned. I got that done and all was well again. A week into my retune I finally push the car hard and the my coolant overflows again. I do some research and start suspecting the head gasket.

Fast forward to now. At this point I can recreate the issue by doing a 4-5 consecutive hard pulls. I feel like I have tested everything I can to see if it is indeed the head gasket and all tests are telling me it is not the head gasket...

Here is what I have tried to do to fix the problem in order:
1. Burped the system with no spill funnel. I do this many times.
2. I replaced both radiator caps with Radium 1.5 bar caps as suggested by AWDTuning. Problem persisted.
3. Inspected coolant lines by thermostat housing, turbo, and radiator. No leaks.
4. Took off undertray for a few days to see if coolant leaked onto the ground. Nothing.
5. Observed coolant levels for a few days and none was lost.
6. Had radiator pressure tested. No leaks.
7. Replaced stock radiator with aluminum Koyo radiator. Problem persisted
8. Switched back to stock radiator caps. Same issue.
9. Brought it to Growler Motorlabs (formerly Cobb Plano). The techs did a chemical combustion gas test which turned up negative. I brought it back on pump gas only as advised and they tested it again. Tests were negative for HG failure.
10. I spoke with Cobb techs and they say it doesn't seem like a head gasket issue. They seemed to not be able to come to a definite conclusion which surprised me.

During this time my coolant temperature never went over 210F!

I also never noticed the typical head gasket signs such as milkshake like residue in oil. I am not losing coolant, it just keeps overflowing. I've heard that a crack in the turbo can cause this but am not sure about that. The car runs fine and doesn't overheat. Im stumped therefore I call upon the mighty power of NASIOC to help me decide...

Do I need a head gasket job or new turbo? Am I insane? Am I going insane? Help!
* Registered users of the site do not see these ads.
D3LTAwrx is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 06-13-2017, 11:36 PM   #2
Half Crazed
NASIOC Supporter
 
Member#: 321842
Join Date: May 2012
Chapter/Region: NESIC
Location: Manchester, NH
Vehicle:
08 420/400 WRB STi
17 Stock WRB WRX

Default

So on #9, they did a hydrocarbon test for coolant? If not, you could try one just to be sure - it's pretty easy.

I've noticed the same thing, it's normal for the coolant to expand under heat and contract once cooled down.. but mine doesn't flow out of the overflow unless I'm hot and taking hard corners (using perrin overflow). When you're under high loads, your temps will shoot up.

Here's a few questions:
  1. When the car is cold, is the overflow empty (or near empty? If stock: at "low" line)?
  2. When the car is cold, and you check your upper reservoir, is it filled to the brim?
  3. Are you using any aftermarket coolant upper/lower lines?
  4. Are you losing any coolant at all (aside from out of the overflow)?
  5. Have you tested/replaced your thermostat? Are you running the proper temperature (possibly stock temps, in your case)?
Half Crazed is offline   Reply With Quote
Old 06-14-2017, 07:54 AM   #3
dUbz
Scooby Newbie
 
Member#: 178290
Join Date: Apr 2008
Chapter/Region: Tri-State
Location: NY
Vehicle:
2011 STi Hatch SSM
2016 DGM STi

Default

i had the same issue on my 05, coolant would volcano out of the overflow. no mixing of oil and coolant, temps would rise slightly biut then go back to normal and stay there. did the test for bad head gasket and it came back good. changed caps, thermostat, radiator and everything you can think of. it turned out it was a blown head gasket.
dUbz is offline   Reply With Quote
Old 06-14-2017, 11:04 AM   #4
gsrcrxsi
Scooby Specialist
 
Member#: 236952
Join Date: Jan 2010
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2010 WRX (SSM)
Stg 2+ 310/370, 6sp R180

Default

yup im betting on it actually being a blown head gasket. it seals enough on regular driving, but you're generating enough combustion pressure to blow past the gasket on hard driving.

it'll only get worse until it's happening all the time.
gsrcrxsi is online now   Reply With Quote
Old 06-14-2017, 11:35 AM   #5
Vicious LSD
Scooby Specialist
 
Member#: 103539
Join Date: Dec 2005
Chapter/Region: Tri-State
Location: Nassau LI
Vehicle:
2009 WRX Premium

Default

Or maybe the heads are lifting under hard loads
Vicious LSD is offline   Reply With Quote
Old 06-14-2017, 12:38 PM   #6
whispering_eye
Scooby Newbie
 
Member#: 348882
Join Date: Mar 2013
Chapter/Region: MWSOC
Location: Royal Oak, MI
Vehicle:
2012 WRX Hatch
WRB

Default

I work in engine validation. Easy test for a headgasket leak. Insert a dongle in the spark plug hole that allows you to pressurize the cylinder at TDC. Use Nitrogen as the molecules are small enough to make it past the head gasket. This should be done in neutral and the car is stable and not able to move. The engine should be warm during testing. Be careful that each cylinder is at TDC exactly; if they are off slightly it will cause the cylinders to spin. To counter this you want to 'test' the cylinder by pushing the compressor side onto the dongle but not fully on, just enough to pressurize it slightly. If the engine spins, readjust TDC and repeat until it doesn't spin. Use 700 PSI of nitrogen. Repeat for all cylinders*.

An example of a failure is coolant overflow; if the coolant level does nothing it is a pass.

I should note that this is generally a specific head gasket test, but if you have a crack in the head that protrudes into the combustion chamber then it will give you a 'false' positive, however, if it passes there is more than likely an issue. Using a borescope could help, but tbh it'd be better just to rip the heads off and inspect.

*I am not responsible for any damage or injury.
whispering_eye is offline   Reply With Quote
Old 06-15-2017, 10:18 PM   #7
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

Quote:
Originally Posted by Half Crazed View Post
So on #9, they did a hydrocarbon test for coolant? If not, you could try one just to be sure - it's pretty easy.

I've noticed the same thing, it's normal for the coolant to expand under heat and contract once cooled down.. but mine doesn't flow out of the overflow unless I'm hot and taking hard corners (using perrin overflow). When you're under high loads, your temps will shoot up.

Here's a few questions:
  1. When the car is cold, is the overflow empty (or near empty? If stock: at "low" line)?
  2. When the car is cold, and you check your upper reservoir, is it filled to the brim?
  3. Are you using any aftermarket coolant upper/lower lines?
  4. Are you losing any coolant at all (aside from out of the overflow)?
  5. Have you tested/replaced your thermostat? Are you running the proper temperature (possibly stock temps, in your case)?
Coolant is at normal levels when cold.
When cold after witnessing bubbles in the overflow, the upper reservoir is NOT full. About and inch below cap.
I'm using silicon perrin upper and lower coolant hoses.
Coolant is only lost from overflow.
Thermostat is fine.
D3LTAwrx is offline   Reply With Quote
Old 06-15-2017, 11:11 PM   #8
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

I'm really considering scheduling something soon and getting a new gasket and ARP head studs. It'll be around 3k for that though
D3LTAwrx is offline   Reply With Quote
Old 06-16-2017, 08:44 AM   #9
Half Crazed
NASIOC Supporter
 
Member#: 321842
Join Date: May 2012
Chapter/Region: NESIC
Location: Manchester, NH
Vehicle:
08 420/400 WRB STi
17 Stock WRB WRX

Default

So air is making its way into the system and coolant cold overflow is normal... Sounds like a head gasket. Coolant won't necessarily be milky on every hg failure.
Half Crazed is offline   Reply With Quote
Old 06-16-2017, 08:58 AM   #10
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

Quote:
Originally Posted by whispering_eye View Post
I work in engine validation. Easy test for a headgasket leak. Insert a dongle in the spark plug hole that allows you to pressurize the cylinder at TDC. Use Nitrogen as the molecules are small enough to make it past the head gasket. This should be done in neutral and the car is stable and not able to move. The engine should be warm during testing. Be careful that each cylinder is at TDC exactly; if they are off slightly it will cause the cylinders to spin. To counter this you want to 'test' the cylinder by pushing the compressor side onto the dongle but not fully on, just enough to pressurize it slightly. If the engine spins, readjust TDC and repeat until it doesn't spin. Use 700 PSI of nitrogen. Repeat for all cylinders*.

An example of a failure is coolant overflow; if the coolant level does nothing it is a pass.

I should note that this is generally a specific head gasket test, but if you have a crack in the head that protrudes into the combustion chamber then it will give you a 'false' positive, however, if it passes there is more than likely an issue. Using a borescope could help, but tbh it'd be better just to rip the heads off and inspect.

*I am not responsible for any damage or injury.
Well damn that is an intense procedure. I'll ask the shop about it but I doubt they are capable of compressing nitrogen to 700 psi. The labor sounds like it would also be expensive.

At some point I have to stop testing. I already paid $250 in diagnostics and don't want to make the job more expensive
D3LTAwrx is offline   Reply With Quote
Old 06-16-2017, 09:53 AM   #11
pigboat_2
Scooby Specialist
 
Member#: 247823
Join Date: May 2010
Chapter/Region: BAIC
Location: Eglin AFB
Vehicle:
2007 STi
SWP

Default

https://youtu.be/U0DdVQoBu4U

Try this test the next time it blows coolant out.
pigboat_2 is offline   Reply With Quote
Old 06-16-2017, 10:27 AM   #12
gsrcrxsi
Scooby Specialist
 
Member#: 236952
Join Date: Jan 2010
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2010 WRX (SSM)
Stg 2+ 310/370, 6sp R180

Default

Quote:
Originally Posted by Half Crazed View Post
So air is making its way into the system and coolant cold overflow is normal... Sounds like a head gasket. Coolant won't necessarily be milky on every hg failure.
this type of failure with combustion gasses making their way into the coolant jacket is the most common type of HG failure for turbo subys.
gsrcrxsi is online now   Reply With Quote
Old 06-16-2017, 10:38 AM   #13
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

Quote:
Originally Posted by pigboat_2 View Post
https://youtu.be/U0DdVQoBu4U

Try this test the next time it blows coolant out.
How am i supposed to sniff the radiator right after doing some heavy pulls? the system would be pressurized and at 210F. I wouldn't be able to safely pull the cap, drain a couple inches, and sniff all before the bubbling stopped...
D3LTAwrx is offline   Reply With Quote
Old 06-16-2017, 10:50 AM   #14
gsrcrxsi
Scooby Specialist
 
Member#: 236952
Join Date: Jan 2010
Chapter/Region: MAIC
Location: Baltimore
Vehicle:
2010 WRX (SSM)
Stg 2+ 310/370, 6sp R180

Default

Quote:
Originally Posted by D3LTAwrx View Post
How am i supposed to sniff the radiator right after doing some heavy pulls? the system would be pressurized and at 210F. I wouldn't be able to safely pull the cap, drain a couple inches, and sniff all before the bubbling stopped...
smell the overflow tank. not the res by the turbo.

edit. after watching the video i see they arent talking about actually smelling it (your use of the word sniff was misleading).

to use that kit, they clearly say to drain the radiator when the car is cool. and not pressurized. THEN do the test.
gsrcrxsi is online now   Reply With Quote
Old 06-16-2017, 11:34 AM   #15
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

True but I have already stated that I had a shop try that method twice on two different fuels.

Would it be safe to drop the coolant level while cold and then so some WOT pulls? That's the only way I can get it to push gasses into the overflow.

If I don't push the car hard there isn't enough gas generated for the block test to suck
D3LTAwrx is offline   Reply With Quote
Old 06-16-2017, 12:41 PM   #16
whispering_eye
Scooby Newbie
 
Member#: 348882
Join Date: Mar 2013
Chapter/Region: MWSOC
Location: Royal Oak, MI
Vehicle:
2012 WRX Hatch
WRB

Default

Try to think about the system in a logical manner. How can the overflow tank end up overflowing? There's realistically two options, excessive pressure in the coolant system or too high of a coolant level to begin with. I'm going to assume you have the coolant at a 'normal' level, so the only other option is that coolant is being over-pressurized and as physics allows us water cannot be compressed so it is moved to the overflow tank.

You did step one in process of elimination and replaced the radiator only to find that it didn't fix it. So the only possible explanation at this point is that the shop that performed the work either did it improperly, or came back with a false negative.

The only last option, which I highly doubt can produce the amount of pressure needed, is the turbo coolant feed/return lines. If there is an internal crack causing compressed air to push coolant around. It would make sense for the false combustion air results. As for a test, I'm afraid I have no answer for that. It would be highly more probable that the head gaskets are on the way out, however.

Best of luck!
whispering_eye is offline   Reply With Quote
Old 06-16-2017, 01:38 PM   #17
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

Quote:
Originally Posted by whispering_eye View Post
You did step one in process of elimination and replaced the radiator only to find that it didn't fix it. So the only possible explanation at this point is that the shop that performed the work either did it improperly, or came back with a false negative.
I did the install myself and have verified that there are no leaks or issues.

Quote:
Originally Posted by whispering_eye View Post
The only last option, which I highly doubt can produce the amount of pressure needed, is the turbo coolant feed/return lines. If there is an internal crack causing compressed air to push coolant around. It would make sense for the false combustion air results. As for a test, I'm afraid I have no answer for that. It would be highly more probable that the head gaskets are on the way out, however.
The turbo coolant lines look good. You don't think an internal turbo crack would produce enough pressure to push coolant?
D3LTAwrx is offline   Reply With Quote
Old 06-16-2017, 05:23 PM   #18
hondaeater69
Scooby Guru
 
Member#: 60324
Join Date: Apr 2004
Location: soon to be somewhere else
Vehicle:
1998 RS

Default

Quote:
Originally Posted by D3LTAwrx View Post
How am i supposed to sniff the radiator right after doing some heavy pulls? the system would be pressurized and at 210F. I wouldn't be able to safely pull the cap, drain a couple inches, and sniff all before the bubbling stopped...


easy, do the test on the overflow tank when it's bubbling, right after the pulls.
hondaeater69 is offline   Reply With Quote
Old 06-16-2017, 05:24 PM   #19
hondaeater69
Scooby Guru
 
Member#: 60324
Join Date: Apr 2004
Location: soon to be somewhere else
Vehicle:
1998 RS

Default

some HG issues only arise under boost. i suspect this is your problem and will probably get worse over time.
hondaeater69 is offline   Reply With Quote
Old 06-16-2017, 05:27 PM   #20
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

So it seems like the general consensus is that I have tried every practical option to test HG or eliminate the overflow issue.

If I do the head gaskets, is it okay if I don't skim the heads as long as the surface is checked with a level?
D3LTAwrx is offline   Reply With Quote
Old 06-17-2017, 05:46 PM   #21
whispering_eye
Scooby Newbie
 
Member#: 348882
Join Date: Mar 2013
Chapter/Region: MWSOC
Location: Royal Oak, MI
Vehicle:
2012 WRX Hatch
WRB

Default

I wouldn't recommend that. If you're going to do headgaskets I would recommend upgrading any internals while you're there. At the very least I would resurface the heads and block. If you plan on upping the power I'd just replace the short lock and reuse the heads. Also when replace the gaskets if you choose just that option then I'd upgrade to cometic gaskets. Just my two cents. ****ty situation makes for fun decisions *insert sarcasm here*.
whispering_eye is offline   Reply With Quote
Old 06-17-2017, 06:03 PM   #22
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

So I am taking the car to AWDTuning to get the head gaskets done with ARP2000 head studs. While they're in there I've opted to get an FP green turbo, TGV deletes, Air pump delete, inlet, oil cooler, and speed density tune from Keith. I was told that I could be tuned to 350-380whp on E85 and that for the 2014 WRX the stock block would still be reliable. They said that the internals for the late models are the same shortblock as the STI except for the Piston dishes so I didn't do any internals. I was also stretching my budget a little already. I pan to tackle that in a couple years hopefully
D3LTAwrx is offline   Reply With Quote
Old 06-17-2017, 07:48 PM   #23
pigboat_2
Scooby Specialist
 
Member#: 247823
Join Date: May 2010
Chapter/Region: BAIC
Location: Eglin AFB
Vehicle:
2007 STi
SWP

Default

Equal length header, an easy 20-30 hp gain and it is technically "preventative maintenance". Because due to the UEL design, cyl 4 gets the hottest and that's why the ringland on cyl 4 usually cracks. EL header eliminates that flaw with the nice power/spool gain.

And I'd do an oil pickup at the same time, Killer B or Moroso.
pigboat_2 is offline   Reply With Quote
Old 06-18-2017, 08:14 PM   #24
whispering_eye
Scooby Newbie
 
Member#: 348882
Join Date: Mar 2013
Chapter/Region: MWSOC
Location: Royal Oak, MI
Vehicle:
2012 WRX Hatch
WRB

Default

Ditto on what pigboat said. I would also look at upgrading clutch as I don't see the stock clutch holding that hp. But I wouldn't get crazy as imo I'd rather burn a clutch than replace a tranny.
whispering_eye is offline   Reply With Quote
Old 06-18-2017, 08:52 PM   #25
D3LTAwrx
Scooby Newbie
 
Member#: 446267
Join Date: May 2016
Chapter/Region: TXIC
Location: Dallas, TX
Vehicle:
2014 WRX Premium
Dark Grey Metallic

Default

I have an ACT Heavy Duty Street clutch already so check on that. Unfortunately, I don't have money for headers at the moment. I'm not trying to max things out since motor will be stock for another year or two.
D3LTAwrx 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 01:49 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2017 Axivo Inc.
Copyright ©1999 - 2017, North American Subaru Impreza Owners Club, Inc.