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Thread: The joys of vacuum leaks

  1. #1
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    The joys of vacuum leaks

    Does anyone know what the size is and the length of the vacuum hose to the brake booster? Any tips and tricks taking the intake manifold off? I'm leaking from my throttle body and rear PCV and the brake booster vacuum is torn right at the end. What's the cold idle on the M60, I would imagine 1k give or take but I've never seen mine above 500 and turning the AC on smoothes out the idle and only raises 30 rpm sometimes.

  2. #2
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    You don't have to lift the manifold to remove the PCV, replace it with the M62 type.
    Quote Originally Posted by WBAD530i View Post
    M62 is an uncontrolled substance, and when abused can cause severe side effects. Do your drugs in moderation kids.

  3. #3
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    What about the vacuum line to the brake booster? I just figured that if both throttle plate and pcv are leaking the manifold itself probably is too or will shortly.

  4. #4
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    What would be the benefit to using the PCV plate from the M62?

  5. #5
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    Is the hose you are looking for #6 on this page?

    http://www.realoem.com/bmw/enUS/show...diagId=34_1870

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  6. #6
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    I think number 7, it goes from the booster being a plastic line to just about the intake manifold where it switches to a rubber one.

  7. #7
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    FCP has them online for $6 and change. If you give me the vin of your car I can confirm the right part number depending on build year, but I put in early 1994 and so that part number should be correct. Copy and paste in google or FCP/Autohausaz etc.

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  8. #8
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    Quote Originally Posted by yukon101 View Post
    What would be the benefit to using the PCV plate from the M62?
    Slightly improved
    Quote Originally Posted by WBAD530i View Post
    M62 is an uncontrolled substance, and when abused can cause severe side effects. Do your drugs in moderation kids.

  9. #9
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    It looked correct, the build date was November of 93 for the 94 year. It looks like you have to remove the manifold to replace it, is that correct?

  10. #10
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    Quote Originally Posted by yukon101 View Post
    It looked correct, the build date was November of 93 for the 94 year. It looks like you have to remove the manifold to replace it, is that correct?
    No it's screwed in, usually torx/ribe.

    Might have to get the expansion tank out of the way.
    Quote Originally Posted by WBAD530i View Post
    M62 is an uncontrolled substance, and when abused can cause severe side effects. Do your drugs in moderation kids.

  11. #11
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    Quote Originally Posted by XAlt View Post
    No it's screwed in, usually torx/ribe.

    Might have to get the expansion tank out of the way.
    Oh okay. I was originally trying asking about the break booster vacuum but I couldn't figure out how to quote from the phone version.

  12. #12
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    I have the new part now, I can unscrew the clamp to one side but what about the other is it clamped on too forcing me to remove the TB?

  13. #13
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    Can you send a photo, im trying to envision what it looks where you are having the issue.

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  14. #14
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    IMG_20170930_134548.jpg
    The cracked one on the left is the one going to the brake booster to which I have a replacement but unsure of how to replace it.
    Last edited by yukon101; 09-30-2017 at 06:18 PM.

  15. #15
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    Look to see if you find that hose at the back end of the engine near the firewall. In my E38 the booster has a hose from it to the PCV in the back of the intake. This may be the case here as well on the M60 which is very similar to the M62.

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  16. #16
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    I have a new M60 PCV in hand too and it has two connections for vacuum so brake booster and fuel pressure.

  17. #17
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    Would I be able to cheat and replace just the elbow by taking the TB off? I also do have vacuum leaks for sure, I unplugged the ICV and it idled even lower than it does nearly to stall and unplugging the MAF had no change at all but the in and out of limp mode made my trans shift even better.

  18. #18
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    Thats where I am losing you, I cant find a good layout of the engine bay and vacuum lines for your M60. Someone else may have to chime in. Wish I saw this before I went to the junkyard, there was a 740il E32 there that I could have referenced.

    So that line that is cracked, does it not extend down to the back drivers side of the engine to the PCV?

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  19. #19
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    Unless I ordered the wrong part it would be just that elbow that is cracked as its only a rubber elbow maybe 4 inches long, it does go back to the rear PCV.

  20. #20
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    Besides the drawings in realoem check also the workshop manual if there are some -although bad quality - drawings https://www.bmwtechinfo.com/repair/main/481en/index.htm
    M60 engine bay details I do not that much.
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  21. #21
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    I felt I should drop by and give a quick update, it turns out the brake booster pulls it's vacuum from the bottom of the throttle body and only the FPR pulls it's vacuum from the rear on the M60.

  22. #22
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    I went to remove the horrible bolts to find they haven't been touched in 26 years and immediately stripped, I grabbed the vice grips and not even they could get it removed no matter how tight I made them. Any idea what I should do? I am 99% sure the rear PCV is the same way and miraculously isn't cracked or broken in any way.
    Owner of two older rare cars,
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  23. #23
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    Try a Screw Extractor, removes snapped off bolt from engine https://www.youtube.com/watch?v=mRGcuGK-POs
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  24. #24
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    Being this is now the case and not being able to remove the rear PCV, does anyone know if it just removes like a normal V8 manifold with it all together still or does something need to happen first.

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