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Half moon seals? (Oil smell in cabin)

Discussion in '1st Gen. Tacomas' started by Seventh, Nov 28, 2012.

  1. Nov 28, 2012 at 4:53 PM
    #1
    Seventh

    Seventh [OP] Insert witty title here

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    I've only had my '01 about a week, and today it started smelling like oil something fierce in the cabin. I've checked the exhaust on startup and after it's warmed up, and it doesn't appear to be burning oil at all.

    I dug around the engine bay, and I don't see any immediate leaks. After some googling, I'm thinking it might be a leaky valve cover gasket. I have the 4Cyl, and I found this post here though it refers to the 22R:

    http://forum.ih8mud.com/79-95-toyota-truck-tech/88153-22re-tune-up.html

    Are those half moon seals part of a valve cover gasket kit? If not, what are they actually called? I don't have the time to change them myself, and I assume they're probably due anyway so I'm just going to have a local shop do it. I'd like to tell them to check those seals in particular, but I'm not 100% sure what they're actually called.

    Any insight would be great!

    Edit: After shopping for a kit, it looks like they are part of it. What are those gaskets actually sealing (what part of the motor)? Apologies for the rookie question! :)
     
  2. Nov 29, 2012 at 8:24 AM
    #2
    Seventh

    Seventh [OP] Insert witty title here

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    Update on this, I took a good long look around my engine bay and I don't think my head gasket is the problem - there's no oil leaks that I can see, nothing leaking under the truck and no spots in the driveway.

    The smell seems to be related to my heater - if I have cold air on, no smell. If I turn the temp to heat and turn it up, it immediately smells like raw oil like crazy.

    Any idea what this could be?
     
  3. Nov 29, 2012 at 8:43 AM
    #3
    85GT 79FJ40

    85GT 79FJ40 Well-Known Member

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    The valve cover gaskets on my V6 were leaking pretty good but it never hit the ground. And it stunk. I would check around the valve cover on the exhaust side for any sign of wetness. But it not smelling when you've got the heater valve closed makes no sense.
     
  4. Nov 29, 2012 at 10:55 AM
    #4
    Seventh

    Seventh [OP] Insert witty title here

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    Definitely no leaks - I spent a couple of hours hunting around for the source of it, and am still scratching my head. ...And I smell like oil from my ride to work, which kind of sucks, haha.

    No idea what this could be.
     
  5. Nov 29, 2012 at 12:14 PM
    #5
    tan4x4

    tan4x4 Well-Known Member

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    Are you sure you are not smelling coolant?
     
  6. Nov 29, 2012 at 1:08 PM
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    Seventh

    Seventh [OP] Insert witty title here

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    Yeah, it's definitely oil. I've owned more than one shitbox back in the day that had coolant problems, I know the difference. :D

    I see no oil around the head gasket at all, no drips, no leaks, but the truck stinks like hell. I'm completely stumped. Checked the oil when I got home and it seems a tad lower than I remember it, but it could be my imagination - going to check it again in the morning and see what's up. Oddly, the engine bay doesn't really smell like oil at all after driving it ~50mi home from work. The cabin smells with the vents on, and if I roll the window down when moving I definitely smell it stronger, but when I got out and sniffed around (heh) the bay, it just smells like any old motor, not like a vat of Mobile 1.

    I hate to bring it to a dealer since they'll no doubt just keep replacing things until they find the problem.
     
  7. Nov 29, 2012 at 7:31 PM
    #7
    kgw

    kgw Well-Known Member

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    Check your valve cover bolts. I have the 3.4 and had a burning oil smell right after I bought it. Tightened up the valve cover bolts and the smell went away.
     
  8. Nov 29, 2012 at 8:18 PM
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    wj32796

    wj32796 Member

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    Just FYI:
    Those half moon seals are used for the cutouts on the head. The cutouts are so you can get a socket on the cam gear bolts.
     
  9. Dec 1, 2012 at 8:48 AM
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    Seventh

    Seventh [OP] Insert witty title here

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    I "fixed" this... And in all my years of wrenching cars and owning the occasional beater, this is a first.

    So as I'd been saying, It smelled like oil, but raw oil - not burning oil (which I am intimately familiar with from owning shitty cars as a kid) and not gear oil (which everyone knows smells like absolute ass). I thought it was associated with my heater, because I'd notice it immediately get VERY strong as soon as I turned the heat on. I'd also notice it when I'd roll the window down.

    As it turns out... It's because of some kind of oil that smells JUST like motor oil that Goodyear puts on their all weather rubber floor mats. Or more accurately, that was on my mats, and all of the mats just like it at the Autozone that I bought them at. (The mats are new, since I've only had the truck a week.)I pulled the mats out to clean them (because I assumed the heater was blowing oil on them) and when I was driving around without them I noticed the smell was gone. So I took a trip up to Autozone to (comically) smell the other mats there, EVERY one of them smelled JUST like my mats.

    So my heater blowing hot air at my feet was heating up the oil on the mats, making it vent all over the cab. When I'd roll the window down, the air circulation blowing into the footwells would waft it up at my face.

    So after a week of wondering where the holy hell this oil smell in my truck was coming from, and why the inside of my truck smelled like oil but not my engine bay... I got new floor mats and problem solved.

    Weirdest fix I can remember. :)
     
  10. Dec 1, 2012 at 9:22 AM
    #10
    maxamillion2345

    maxamillion2345 Go home if you don't like guns liquor and whores.

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