Worn emission hoses = oil leaks...

Julio Bro! · 05-16-2017, 06:13 PM

I have a 2009 WRX from which oil is leaking. The culprit are the emission hoses that connect to the block and go up. There are two connections at each side of the engine (why two?), but seem to be different in size (diameter).

They are leaking at more than one spot, so replacement of the whole set or assembly is recommended. The problem is sites seem to sell the hoses individually (http://estore.subarupartswarehouse.c...12-050-07.html), not, like, in a replacement kit or assembly.

So, two options; is it a good idea to replace them with silicone hoses? Is there a silicone assembly or kit?

If not, is there a part number for the whole set or some site that sells a replacement kit?

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thewolfe · 05-16-2017, 06:44 PM

One is for crankcase ventilation, the other is a balance tube. I would stick with oem on those hoses as they are molded to fit. Silicone would probably work okay though. If you have lots of oil coming out of those tubes then you have some excessive blowby.

Samurai Jack · 05-17-2017, 12:14 PM

You are much better of sticking w/the OEM hoses. The are already pre-formed for the best fit without any kinks. You do not want blockage for oil vapors to build up and the crankcase not to vent properly.

These are not sold in sets. They are sold individually.

and like thewolfe said, if they are actually leaking oil, you have a lot of oil blowby and it's building up inside the hoses ( which is a huge amount of blowby ) or you have a blockage somewhere causing the oil vapor to build up and then leak somehow ( cracked hoses? )

Make sure when you replace the hoses that any other vent tubes they connect to are free and clear

Julio Bro! · 05-18-2017, 12:51 PM

Thanks for your advice. As for the leaks, the hoses are hard and brittle; the issue began a few months after replacing the gaskets (or fixing) the cylinder heads. I'm guessing the handling caused weakening and cracks; you can see them expanded at connections.

So, I'll verify exactly which hoses and go for OEM. Thanks again.

No Go · 05-18-2017, 04:00 PM

Or go half assessed and take a sample to Autozone and buy heater hose...likely that is what someone did to your car.

Note: someone else just posted the above on the same question/different thread.

I would recommend new OEM like others have posted above. My originals lasted to 190,000 miles...no leaks. I replaced with OEM...a high quality rubber.

schoes · 05-19-2017, 08:09 AM

Quote:

Originally Posted by No Go

Or go half assessed and take a sample to Autozone and buy heater hose...likely that is what someone did to your car.

OEM or SAE 30R7 rubber hose. These are oil resistant and won't 'weep' the oil vapors like a heater hose would. Researching AOS threads may help you.

No Go is right, heater hose is probably what is on the car now. Unless they truly are very old.

mrsaturn7085 · 05-19-2017, 12:17 PM

I always thought silicone was more prone to fluid leakage due to 'weeping'. Heater hoses should be fine (though I still recommend molded OEM hoses) - usually the key factor in automotive hose selection is whether or not you're running brake fluid through the line (and pressure requirements). Fuels are a different story, entirely.

Julio Bro! · 05-21-2017, 02:14 PM

These are the emissions hoses, EGR-PCV and such 2 or 3 sections are leaking. I have 89K in the odometer, plus Puerto Rico is very hot in the summer...up to 93 degrees daily, suddenly it rains. Quite the drastic change in temperatures for 9 years.

05-16-2017, 06:13 PM	#1
Julio Bro! Scooby Newbie Member#: 192923 Join Date: Oct 2008	Worn emission hoses = oil leaks... I have a 2009 WRX from which oil is leaking. The culprit are the emission hoses that connect to the block and go up. There are two connections at each side of the engine (why two?), but seem to be different in size (diameter). They are leaking at more than one spot, so replacement of the whole set or assembly is recommended. The problem is sites seem to sell the hoses individually (http://estore.subarupartswarehouse.c...12-050-07.html), not, like, in a replacement kit or assembly. So, two options; is it a good idea to replace them with silicone hoses? Is there a silicone assembly or kit? If not, is there a part number for the whole set or some site that sells a replacement kit? * Registered users of the site do not see these ads.

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05-16-2017, 06:44 PM	#2
thewolfe Scooby Newbie Member#: 427424 Join Date: Aug 2015 Location: Portland, OR Vehicle: 2014 wrx hatch black	One is for crankcase ventilation, the other is a balance tube. I would stick with oem on those hoses as they are molded to fit. Silicone would probably work okay though. If you have lots of oil coming out of those tubes then you have some excessive blowby.

05-17-2017, 12:14 PM	#3
Samurai Jack Scooby Guru Member#: 21145 Join Date: Jul 2002 Chapter/Region: NESIC Location: Not in my own time Vehicle: 2002 Enemy of Aku	You are much better of sticking w/the OEM hoses. The are already pre-formed for the best fit without any kinks. You do not want blockage for oil vapors to build up and the crankcase not to vent properly. These are not sold in sets. They are sold individually. and like thewolfe said, if they are actually leaking oil, you have a lot of oil blowby and it's building up inside the hoses ( which is a huge amount of blowby ) or you have a blockage somewhere causing the oil vapor to build up and then leak somehow ( cracked hoses? ) Make sure when you replace the hoses that any other vent tubes they connect to are free and clear

05-18-2017, 12:51 PM	#4
Julio Bro! Scooby Newbie Member#: 192923 Join Date: Oct 2008	Thanks for your advice. As for the leaks, the hoses are hard and brittle; the issue began a few months after replacing the gaskets (or fixing) the cylinder heads. I'm guessing the handling caused weakening and cracks; you can see them expanded at connections. So, I'll verify exactly which hoses and go for OEM. Thanks again.

05-18-2017, 04:00 PM	#5
No Go Scooby Newbie Member#: 38928 Join Date: Jun 2003 Location: Florida Vehicle: 2004 153 MPH STI Silver	Or go half assessed and take a sample to Autozone and buy heater hose...likely that is what someone did to your car. Note: someone else just posted the above on the same question/different thread. I would recommend new OEM like others have posted above. My originals lasted to 190,000 miles...no leaks. I replaced with OEM...a high quality rubber.

05-19-2017, 12:17 PM	#7
mrsaturn7085 Scooby Specialist Member#: 375462 Join Date: Dec 2013 Location: Portland, OR Vehicle: 2006 Impreza WRX STI WR Blue	I always thought silicone was more prone to fluid leakage due to 'weeping'. Heater hoses should be fine (though I still recommend molded OEM hoses) - usually the key factor in automotive hose selection is whether or not you're running brake fluid through the line (and pressure requirements). Fuels are a different story, entirely.

05-21-2017, 02:14 PM	#8
Julio Bro! Scooby Newbie Member#: 192923 Join Date: Oct 2008	These are the emissions hoses, EGR-PCV and such 2 or 3 sections are leaking. I have 89K in the odometer, plus Puerto Rico is very hot in the summer...up to 93 degrees daily, suddenly it rains. Quite the drastic change in temperatures for 9 years.