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Thread: Pretty big oil leak coming from the front of the engine m30b35 any ideas? HELP PLEASE

  1. #1
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    Pretty big oil leak coming from the front of the engine m30b35 any ideas? HELP PLEASE

    Hi,

    So I recently did a headgasket and timing chain job on my 1990 535i, and it started right up and works nice, but it drips oil on the bottom where the adjuster for the a/c belt is! The oil pan does not seem to be leaking, and the timing chain covers have new gaskets and were sealed up pretty nicely to my knowledge (plus they look clean, no oil from there) so I have no idea where the oil is coming from, it seems to be running along the front of the engine and accumulating below the a/c compressor where it drips into a puddle . Any ideas what it could be? Or should I bite the bullet and take it to a shop to see if they can fix the problem?

    Paolo

  2. #2
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    Suck
    Well, it's an m30, so really the answer should be more like "Where isn't my engine leaking oil from?"

    But all joking aside, it's most likely that you borked something on the install. What you need to do is clean all the oil off and run the engine, then find where it's leaking from. Get a flashlight and really get in there and look around. It's probably a chain tensioner not installed tight enough, or without the crush washer to seal it, or something like that. It's entirely possible you didn't install the chain guide covers properly, or even that the crank position sensor mount bolts have loosened up.

    Go ahead and bite. Plenty for everyone.

  3. #3
    Join Date
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    My thought is the chain covers where they meet the HG. Especially at the corners.
    1994 550iT/6 : 2003 330i/5

  4. #4
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    click here http://twrite.org/shogunnew/topmenu.html go to links & lots of diy>>other diy sites>>there must be a link to Jon Evans, he has a write up with pics for the M30 oil leak in front
    Shogun tricks and tips for the E32 series are HERE!

  5. #5
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    Thats the thing, none of these areas are dirty, only the a/c compressor and the adjuster where the oil tends to drip. The car is also giving me a "oil pressure sensor +" on the dash, so I think this might have something to do with it, faulty oil sending unit? Any thoughts?

  6. #6
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    chain tensioner bolt. Replace the o-ring
    _____________________
    1990 M5 Euro (French)

  7. #7
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    My thought is the chain covers where they meet the HG.
    Last edited by dorcewangy; 06-21-2014 at 03:32 AM.

  8. #8
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    Quote Originally Posted by jint45 View Post
    chain tensioner bolt. Replace the o-ring
    I had a pesky oil leak from that area on my '81 745i (M106, turbo version of M30) that I couldn't stop either. The problem was a hairline longitudinal crack in the "snout" of the front cover (the part on the right side that the tensioner spring/plug fit into). Tightening the plug just made it leak worse. It probably could have been TIG welded but I just got a good used front cover (and replaced the front main seal too).
    '98 740iL E38 201k, TCG at 190k, 5HP24 at 195k
    '97 540i/6 E39 Dinan blower & stage 1 suspension 114k
    '93 525i E34 "Golf Ball" (hail damaged) 334k

  9. #9
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    Yeah I am going to try and wash that whole area, and then see where its leaking from! Hopefully its something simple, didnt see any cracks on the timing covers when I pulled them off for the hg/tm-c job. It only leaks after its been driven too, its been parked for a few days without use, and no leak whatsoever.

  10. #10
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    Quote Originally Posted by jint45 View Post
    chain tensioner bolt. Replace the o-ring
    Apologies for resurrecting a dead thread, is the chain tensioner bolt something that can be unscrewed and screwed right back in after changing the o-ring or washer? Or are there some preliminary steps and precautions that need to be taken?

  11. #11
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    A rug to catch some oil when undoing the tensioner bolt is all you need.

  12. #12
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    Quote Originally Posted by Mless5 View Post
    A rug to catch some oil when undoing the tensioner bolt is all you need.
    Sweet, thanks

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