PCV and Crankcase ventilation
NEWS
 
+ Reply to Thread
Results 1 to 22 of 22
  1. #1
    Neutral
    Join Date
    Nov 2009
    Location
    Utah
    Posts
    11

    PCV and Crankcase ventilation

    I checked my PCV system today and the side leading back to the crankcase does not have a lot of vacuum. It has some but it would barley stick to the end of my finger. It that normal? Or do I need to replace the suction/vacuum booster pump.http://www.ecstuning.com/Volkswagen-...7844/ES261411/I have an 2002 passat 1.8T with 65,000 miles. Also has anyone tried just venting the crankcase breather hose to atmosphere? Instead of worrying all the time and trying to maintain the PCV system. You could stub the breather hose into the air intake box and put a small K&N filter on the end of it. http://www.knfilters.com/vent.htmAny thoughts?

    Thanks
    Jed

  2. Remove Advertisements
    VW Passat Forum
    Advertisements
     

  3. #2
    4th Gear
    Join Date
    Sep 2007
    Location
    Long Island NY
    Posts
    3,768
    Don't know about the K&N thing but I have the same year and engine, and my suction valve was glogged at the same mileage. I found it due to a head gasket leak (from pressure buildup) which was fixed by replacing the part.

  4. #3
    Neutral
    Join Date
    Nov 2009
    Location
    Utah
    Posts
    11
    Was it a head gasket leak or a valve cover gasket leak? I would be really worried if it caused a head gasket leak, I am not even sure that is possible. Here are some interesting links about PCV. http://www.burtonpower.com/technical...er_system.aspx
    http://www.secondchancegarage.com/public/239.cfm
    Back in the day all crankcases were ventilated to the atmosphere.

  5. #4
    Moderate Moderator Steve in Chicago's Avatar
    Join Date
    Jul 2008
    Location
    Chicago
    Age
    51
    Posts
    14,548
    Quote Originally Posted by jatherley View Post
    Back in the day all crankcases were ventilated to the atmosphere.
    Back in the day, they did a lot of things they no longer do.

  6. #5
    2nd Gear
    Join Date
    Jun 2009
    Location
    Illinois
    Posts
    631
    i replaced the vac hose that went from the valve cover to the airbox on my old '02 Lancer with a breather filter like the ones you linked. i saw no side effects. wasn't sure how that'd go on the Passat since its turbo...might give it a go and see what happens.

  7. #6
    2nd Gear
    Join Date
    May 2002
    Location
    Portland OR USA
    Posts
    807
    Jatherley - Yes you can have a head gasket oil leak. Prior to the PCV valve crankcase vapors were pulled out of the engine by what was called a draft tube. This tube ran below the car. A vacuum was created when the vehicle was in motion pulling out the vapors.

    Those are great links by the way!

    Just venting the breather hose to atmosphere would cause the oil to become contaminated by blow-by gasses quicker. A better solution would be to increase the volume of blow-by gasses the PCV system can handle.

  8. #7
    3rd Gear
    Join Date
    Apr 2007
    Location
    Jerseys Finest
    Posts
    1,199
    you can also look into an oil catch can, which would be connected in numerous fashions to the crankcase breaker hose for ventilation. some people follow the same stock ventilation pattern which connects to your TIP by the puck valve & metal pipe that wraps around the engine..

    others will plug the hole in the TIP & have a filter on top of the catch can that would vent to the atmosphere...

    the catch can will catch blow by & vapors from the crankcase & prevent them from going back into your intake tract & clogging prone areas..

  9. #8
    Neutral
    Join Date
    Nov 2009
    Location
    Utah
    Posts
    11
    Quote Originally Posted by TurboJim View Post
    Jatherley - Yes you can have a head gasket oil leak. Prior to the PCV valve crankcase vapors were pulled out of the engine by what was called a draft tube. This tube ran below the car. A vacuum was created when the vehicle was in motion pulling out the vapors.

    Those are great links by the way!

    Just venting the breather hose to atmosphere would cause the oil to become contaminated by blow-by gasses quicker. A better solution would be to increase the volume of blow-by gasses the PCV system can handle.
    I know you can have a head gasket oil leak, I just don't think it would be casued by high crankcase pressure, however, I could be wrong. I would think the high crankcase pressure would cause other gaskets to go bad long before the head gasket.

    To maintain the PCV system are most of you just replacing the PCV valve or are you replacing more, puck valves, hoses, etc? Obviously I would replace the hoses if by visual inspection they looked bad.

  10. #9
    4th Gear
    Join Date
    Sep 2007
    Location
    Long Island NY
    Posts
    3,768
    Quote Originally Posted by jatherley View Post
    Was it a head gasket leak or a valve cover gasket leak? I would be really worried if it caused a head gasket leak, I am not even sure that is possible. Here are some interesting links about PCV. http://www.burtonpower.com/technical...er_system.aspx
    http://www.secondchancegarage.com/public/239.cfm
    Back in the day all crankcases were ventilated to the atmosphere.
    Oh yeah sorry, it was a valve cover gasket.

    Yup back in the day we didn't have emissions laws, and that's still an "emission".

    As for what to replace, a lot of guys I've seen on here do everything, some just do a few key trouble prone ones. Though which ones are prone depends on what motor you have and who you ask... I just did the one that I had to and then all the easy ones (3 I think). I still have a new puck valve, but for the life of me I cant see how that thing can clog.

  11. #10
    In reverse, but chained to a tree.
    Join Date
    Sep 2006
    Location
    plano/waco, Tx
    Age
    26
    Posts
    13,315
    Blog Entries
    5
    Quote Originally Posted by Steve in Chicago View Post
    Back in the day, they did a lot of things they no longer do.
    back in the day they didn't have over-engineered pcv systems

  12. #11
    Neutral
    Join Date
    Nov 2009
    Location
    Utah
    Posts
    11
    Quote Originally Posted by UrbanLegend View Post
    Oh yeah sorry, it was a valve cover gasket.

    Yup back in the day we didn't have emissions laws, and that's still an "emission".

    As for what to replace, a lot of guys I've seen on here do everything, some just do a few key trouble prone ones. Though which ones are prone depends on what motor you have and who you ask... I just did the one that I had to and then all the easy ones (3 I think). I still have a new puck valve, but for the life of me I cant see how that thing can clog.
    I am going to replace the PCV valve and do an inspection on the check valves to ensure they are working. I think those are the only valves you need to worry about. Correct me if I am wrong.

  13. #12
    Neutral
    Join Date
    Nov 2009
    Location
    Utah
    Posts
    11
    Quote Originally Posted by sipes216 View Post
    back in the day they didn't have over-engineered pcv systems
    These systems get even more complicated when you add a turbo.

  14. #13
    Neutral
    Join Date
    Mar 2009
    Location
    SaoPaulo, Brazil
    Posts
    12

    Oil Leak by PCV system

    Hello friends, I have a b5 passat 99 1.8t with 68k miles (110k km) and it leaks oil by PCV system. About 10k miles I replaced entire PCV (Complete 1.8 PCV System DIY (AEB)) but since I bought the car, 3 years ago, it low engine oil. I already replaced my turbo or anything that can cause this oil consumption but, last at week, I disconnected the PCV valve from air intake, leaving it at atmosphere and have isolated the hole of entry what made me found from where the oil was comming. A lot of oil!!! My engineer told that it can be caused by leakage through the rings, but I think that it is too expensive only to "think". Is there any way to be sure before disassemble the engine? Thanks a lot!!! (sorry bad english).

  15. #14
    2nd Gear
    Join Date
    Oct 2001
    Location
    Cranbury,N.J.
    Posts
    754
    back in the day they didn't have over-engineered pcv systems

    True enough but they did have roads with oily black stripes down each lane - guess where that came from !

  16. #15
    Neutral
    Join Date
    Nov 2006
    Location
    Flower Mound, TX
    Posts
    35
    I replaced every vacuum tube, check valve, the PCV valve and the DV and cleaned out the metal vent tubes on my 2002 1.8T at 50,000 miles. Before that it was running terribly, but most concerning, it was blowing through oil like crazy. The pressure was pushing oil through the valve cover gasket. After the changeout it stopped using oil (even though I still haven't gotten to the valve cover gasket yet) and runs 100% better. Replacing all that stuff is a HUGE PITA though. I had to take off the intake manifold to get at everything but it was worth it.

  17. #16
    3rd Gear
    Join Date
    Jan 2009
    Location
    KW & Toronto
    Age
    13
    Posts
    2,023
    Quote Originally Posted by texmln View Post
    I replaced every vacuum tube, check valve, the PCV valve and the DV and cleaned out the metal vent tubes on my 2002 1.8T at 50,000 miles. Before that it was running terribly, but most concerning, it was blowing through oil like crazy. The pressure was pushing oil through the valve cover gasket. After the changeout it stopped using oil (even though I still haven't gotten to the valve cover gasket yet) and runs 100% better. Replacing all that stuff is a HUGE PITA though. I had to take off the intake manifold to get at everything but it was worth it.
    What guide did you use to take off the manifold?

  18. #17
    3rd Gear
    Join Date
    Jan 2009
    Location
    Waterloo, Ontario
    Age
    25
    Posts
    1,518
    I think it's possible without taking the manifold off. Moving the coolant tank should help in getting yours down below the manifold.

  19. #18
    3rd Gear
    Join Date
    Apr 2007
    Location
    Jerseys Finest
    Posts
    1,199
    yeh just flip the coolant tank over & this will give you access to under the manifold

  20. #19
    Neutral
    Join Date
    Mar 2009
    Location
    SaoPaulo, Brazil
    Posts
    12
    Hello TEXMLN, I did the PCV replace tutorial Complete 1.8 PCV System DIY (AEB) but I didnĀ“t clean the metal tube that pass behind engine block and did not change my DV. By the way I will do it and after tell to you. I think that is not necessary tho take out the intake manifold, only the coolant tank. Thank you very much.

  21. #20
    Neutral
    Join Date
    Nov 2006
    Location
    Flower Mound, TX
    Posts
    35
    I think I used the guide here at passatworld referenced by vagbestech.... but I have an AWM so it was slightly different if I recall but close enough not to be a problem. Remember to take note of which direction your check valves are going. Once you pull all that stuff off it's easy to get lost and forget. Take some pictures for reference.

    I moved my coolant tank out of the way too but even with the extra space I still had trouble pulling apart the connections under the intake manifold. Removing the manifold wasn't too terrible, though a few of the nuts/bolts were a little difficult to reach. Just be careful about dropping them into the intake, you really have to pay attention and not let them get away from you. After the manifold was off I stuffed rags into the ports to protect them. I did end up dropping one or two bolts into the engine (not the ports) that were really tough to find - they got hung up on the block and never hit the ground.

    My metal tubes were loaded with gunk and I went through a couple of cans of brake cleaner before they were in good shape again.

    Don't forget to replace the suction pump while you're at it since it is an integral part of the vacuum/PCV system. There's also a special three way check valve around the suction pump that is different from the others and I couldn't find it ANYWHERE - even the dealer didn't have it. I ultimately found it at autopartswarehouse.com, which I thought was odd since they don't specialize in VW. I just checked and they still sell it as part number W0133-1808885. You'll find it under the Engine section in the Vacuum System subdirectory.

    I was really impressed by how well the engine ran after this job. I'm convinced that a full vacuum/PCV system overhaul is required on the 1.8T every 50k no matter what. I'm also convinced that a bad PCV system is behind many of the problems owners experience with this engine, particularly oil related failures.

    I don't think the dealers even recommend servicing the PCV system, and if they do, I'm sure their pricing is crazy because this job sucks. Leave yourself plenty of time to complete it and be patient.

  22. #21
    Neutral
    Join Date
    Mar 2009
    Location
    SaoPaulo, Brazil
    Posts
    12
    Thank you texmln, my trouble was a deffective bleeder valve (035-103-245-A) that leaks boost to crankcase. The old one that I kept was in much better condition. Thank you!

  23. #22
    Neutral
    Join Date
    May 2010
    Location
    Houston
    Posts
    3
    Anyone have an updated link to this DIY? All of the pictures seem to have died off.

    Thanks!

  24. Remove Advertisements
    VW Passat Forum
    Advertisements
     

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Powered by vBadvanced CMPS v4.1.2