Clogged PCV Valve and oil consumption

[beny5473]

I have a 2006 Subaru legacy 2.5l with just over 200k miles i bought with a blown head gasket for cheap to fix up for a first. I resealed the engine and sent the heads to the machine shop to get reworked and put used MLS head gaskets, there was still pretty good crosshatching in the bores. I did purchase a new subaru branded PCV valve from amazon and looked like it was in the Subaru original packaging. I noticed some oil consumption, about 1 qt every 1800 miles when i changed the oil and an oil burning smell when running. I took the PCV valve off and it did not rattle, so i cleaned it out with brake clean until it started rattling again. I've done this twice now at each oil change.

Could this just be a faulty PCV valve, or could there be an underlying issue causing this?

 

[bmart]

Yes. Could be either. Do you know oil consumption before you touched it?

A non-Subaru non-metal gasket may give you some troubles...

 

[beny5473]

oops, didnt mean to type used MLS gaskets. They were all new and recommended from a retired subaru tech that has guided me on getting this back up and running.
Not sure about the oil consumption when i bought it. but i have gotten it to be better since cleaning the PCV valve each oil change and ran some cleaner through it before changing the oil

 

[bmart]

Old Subaru engines with high miles do tend to use oil. I have 215k on my '00 Legacy GT and it uses 1 qt every 2k-2.5k miles. Oil is cheap and I'm about to extend my changes from 5k to 7.5k because of the new oil between cycles.

It is still, by a long shot, the best car I've ever owned. It just did a track day a few weeks back and was flawless.

 

[beny5473]

awesome. i am currently doing on about 4-5k miles between oil changes using full synthetic 10w40.
I might buy another PCV valve directly from Subaru just incase this one was fake. i heard aftermarket ones just don't work.

 

[flatfoot55]

Have you done a compression test?

 

[beny5473]

Have you done a compression test?

I have not. It runs pretty good though. I did check the oil level this weekend and it is using even less oil than before. maybe 1-1.5 qt in 3500 miles. She said it just recently started having the oil burning smell so its lasting longer before getting clogged. Hopefully it keeps improving over time as i keep the pcv valve clean and using good quality oil

 

[Stevsub4]

Old Subaru engines with high miles do tend to use oil. I have 215k on my '00 Legacy GT and it uses 1 qt every 2k-2.5k miles....

I just hope the FB25 engines will get 200k+ miles without major repairs. Although head gasket trouble isn't common with those cam carrier leaks are. I've had many older Subarus with the EJ25s and wish I kept one.

A quart every 2k or so miles on an engine with 215k really doesn't seem bad at all.

 

[Daniel Renaud]

I have a 2006 Subaru legacy 2.5l with just over 200k miles i bought with a blown head gasket for cheap to fix up for a first. I resealed the engine and sent the heads to the machine shop to get reworked and put used MLS head gaskets, there was still pretty good crosshatching in the bores. I did purchase a new subaru branded PCV valve from amazon and looked like it was in the Subaru original packaging. I noticed some oil consumption, about 1 qt every 1800 miles when i changed the oil and an oil burning smell when running. I took the PCV valve off and it did not rattle, so i cleaned it out with brake clean until it started rattling again. I've done this twice now at each oil change.

Could this just be a faulty PCV valve, or could there be an underlying issue causing this?

Always use OEM parts not the cheap chinese crap the will damage the car later on.

 

[Raymond3006]

"Burning" (using/loosing) oil due PCV issues is due to pressurizing of the Crank-Case with excess blow-by of compression by-products : solving them is "simply" ( !!!!! ) a matter of getting the Crank-Case pressure back below atmospheric ... (!) , so that Oil does not escape : First , thru your Engine SEALS ; and Second, thru the PCV itself, and back into the Intake-Air-System. As Blow-By reaches high levels, the PCV just gets more plugged with Oil & By-Products , as they are carried by high volumn flows as "windage" ! When this happens , your only recourse is to go The-Catch-Can approach ... which becomes a self defeating process !

Not "easy" for those who missed out on the 1960-1990 Engine Designs ... !